# Garn is up and running



## curtis (Jan 4, 2014)

Was able to fill my garn 1500 today and get the new controller wired up. I started a fire about an hour ago and the tank temp is slowly rising. Everything went together great with the exception of one copper union in the house that just won't seal. 

I had some water leaking out the back of the flue but I think that was just because the water was only 45  degrees. I'm glad I can shut off the oil furnace and heat my house with the garn the rest of the year. I've got about 6 cords of ash stacked up ready to burn.


----------



## BoilerBob (Jan 4, 2014)

Awesome, Congrats

Got pics of first fire?


----------



## curtis (Jan 4, 2014)

BoilerBob said:


> Awesome, Congrats
> 
> Got pics of first fire?


----------



## kjahnz (Jan 4, 2014)

congratulations on your first fire. that fire box is HUGE. the water leaking, maybe from the moisture your cooking out of your refractory. seems like your timing is pretty good also, gonna get cold the next few days.


----------



## curtis (Jan 4, 2014)

kjahnz said:


> congratulations on your first fire. that fire box is HUGE. the water leaking, maybe from the moisture your cooking out of your refractory. seems like your timing is pretty good also, gonna get cold the next few days.



Ya the moisture from the flue is now gone. I just read in the manual that if the water temp is low like mine was there will be condensation in the flue.

So far my tank temp is 155 and my supply temp is 119. Will it take awhile for all the water in the tank to equalize in temperature? 

Also the difference between the supply and return temp at the garn is only 2-3 degrees. Granted that's with no load on it but I thought for a 200+ ft loop that that's pretty good. I used 1.25 rehau insulated pex.


----------



## kjahnz (Jan 4, 2014)

I don't have a garn, wish I did. Happy heating.


----------



## bpirger (Jan 4, 2014)

Congrats!  First fire in our 1500 on 17NOV2010...and not a drop of oil burned since then.  We are pleased with our Garn.

Search through for Garn threads on temperature stratification....all sorts of things you will get used to.  Where are you measuring the 119 supply temp?  All depends on your HX and everything else.

We have radiant heat and also heat our DHW.  We can use water temps down to about 100-110 to heat the radiant (depends on the temp outside) but for DHW needs to be 120ish.

I have an 80 plate HX and I'll measure about a 20-25 degree temp difference between the tank display and my supply in the house....many hours (12-16) after a burn.  Right after a burn they will be much closer.   Someday I will have to install my temp sensors everywhere and then I will really understand just what is going on.  Past measurements showed me that I was within a degree or two on either side of the HX.   I wanted to be sure I could use the water down to the 100 degree range.  I'm pretty sure the actual supply water temp can vary significantly from what the tank temp display says....despite the level of the supply line and thermo wells being rather close.

My only other comment is that the target temp for the Garn tank is supposed to be 190 according to Dectra.  Higher temps apparently will speed up the breakdown of the tank chemistry.  I have never measured the bottom, middle, and displayed tank temp (near the top), but after many hours, there is quite a stratification built up.  You can easily feel it with your hand....


----------



## curtis (Jan 5, 2014)

bpirger said:


> Congrats!  First fire in our 1500 on 17NOV2010...and not a drop of oil burned since then.  We are pleased with our Garn.
> 
> Search through for Garn threads on temperature stratification....all sorts of things you will get used to.  Where are you measuring the 119 supply temp?  All depends on your HX and everything else.
> 
> ...



Well I went to bed with the tank temp reading 190 and just a small bit if wood left in the firebox. Went out to check it just now and the tank temp is reading 174. Kept the house at 71 all night. The copper union must have sealed itself up once it got warm water running through it. Everything seems to be working great on it so far. 

When judging wether or not to do another burn, do you guys go by the tank temp sensor or the supply temp? I have my supply temp sensor mounted on black iron pipe about 6" from the garn itself.


----------



## Robert V (Jan 5, 2014)

I have only been running my garn 2000 this season but I quit paying attention to the tank temp as it never matches the supply temp except after a full burn.. The way I see it the water going to my house is what matters. The garn seems to leave a level of hot water at the top of the tank all the time. I think it is because the water outlet is aprox a foot lower then the actual water level so I think the top layer of water never really gets used. On the other hand perhaps this helps keep the water under it warm. Any one else ever notice this?


----------



## curtis (Jan 5, 2014)

Robert V said:


> I have only been running my garn 2000 this season but I quit paying attention to the tank temp as it never matches the supply temp except after a full burn.. The way I see it the water going to my house is what matters. The garn seems to leave a level of hot water at the top of the tank all the time. I think it is because the water outlet is aprox a foot lower then the actual water level so I think the top layer of water never really gets used. On the other hand perhaps this helps keep the water under it warm. Any one else ever notice this?



So do you burn until your supply is 180-190? What does your tank temp read when you do that then? I just don't want to boil my water in the garn by over firing.


----------



## Robert V (Jan 5, 2014)

The two temps will just about match after a burn. My goal temp is 190. Usually it will say the tank temp is about 195 and supply temp 190. Of course its not perfect every time but I am sure I will get better with time. I did boil mine once and it pushed water out the overflow all over my floor. Over all I am super happy with it so far. I only burn it once per day and it usually goes 3 to 4 hours.  One thing I am wondering is why my flue temps are so high. I am burning decent dry hardwood mixed with some dry soft wood and my temps during a full burn with 135 deg ish water run 400 to 450 deg. Sometimes it will peak just over 500 on a hot load. I would like to here from experienced garn owners if this is normal. I super cleaned all the tubes, passages, wheel, ect before the season. 

Curtis,
Your running a air/water HX in your furnace right? I am running panel rads on the main floor and a air/Water HX in the basement. I have found that the air/Water HX runs non stop when the water temp drops below 130 ish.


----------



## curtis (Jan 5, 2014)

Robert V said:


> The two temps will just about match after a burn. My goal temp is 190. Usually it will say the tank temp is about 195 and supply temp 190. Of course its not perfect every time but I am sure I will get better with time. I did boil mine once and it pushed water out the overflow all over my floor. Over all I am super happy with it so far. I only burn it once per day and it usually goes 3 to 4 hours.  One thing I am wondering is why my flue temps are so high. I am burning decent dry hardwood mixed with some dry soft wood and my temps during a full burn with 135 deg ish water run 400 to 450 deg. Sometimes it will peak just over 500 on a hot load. I would like to here from experienced garn owners if this is normal. I super cleaned all the tubes, passages, wheel, ect before the season.
> 
> Curtis,
> Your running a air/water HX in your furnace right? I am running panel rads on the main floor and a air/Water HX in the basement. I have found that the air/Water HX runs non stop when the water temp drops below 130 ish.



Just got done with a burn and the tank temp is 184, the supply is 160. They never seem to get much closer than that. Idk if the sensors are reading right or not.


----------



## TCaldwell (Jan 5, 2014)

Robert,  for the wood you are burning those flue temps would be '' normal'', if you are not puffing your wood is very good. If you are puffing add some larger splits or a few pieces of higher moisture % wood.


----------



## Robert V (Jan 5, 2014)

The supply/return temp sensors are strapped to the pipes right at the garn? Do you have any other temp sensors other then the garn controller? Are you still on your first couple burns? I wonder if your just getting tank stratification. Mine did some strange things on the first few burns. Does your garn water circulate constantly?


----------



## curtis (Jan 5, 2014)

Robert V said:


> The supply/return temp sensors are strapped to the pipes right at the garn? Do you have any other temp sensors other then the garn controller? Are you still on your first couple burns? I wonder if your just getting tank stratification. Mine did some strange things on the first few burns. Does your garn water circulate constantly?



Yes they are strapped onto the black pipe that's connected to the garn, about 6" from the boiler. I only have one other mechanical temp sensor in the return and it reads about 170. 

Yea today is my second day operating the boiler, fired it last nite for the first time and today was the second fire I had in it.


----------



## Robert V (Jan 5, 2014)

Caldwell,
Ok that's cool I did get some puffing early in the season when I was first getting to know it but none now. It seems to pick up temp quick so I figured the tubes were not coated too bad. Is 3-4 hours a normal burn time to climb from 120 to 190?


----------



## curtis (Jan 5, 2014)

Oh and I have another question for you guys. Did you silicone and screw the exhaust pipe to the boiler? I haven't and it seemed it would make it a pain to take off if you ever had too.


----------



## Robert V (Jan 5, 2014)

curtis said:


> Yes they are strapped onto the black pipe that's connected to the garn, about 6" from the boiler. I only have one other mechanical temp sensor in the return and it reads about 170.
> 
> Yea today is my second day operating the boiler, fired it last nite for the first time and today was the second fire I had in it.


 
Well something doesn't add up. If the garn control says you have 160 going out but your mechanical gauge says 170 coming back then something is not telling the truth. Does the garn return temp on the controller match the analog? You might just want to give it a few more burns to let all the water come up to temp. Have you done the old touch/feel the pipes trick?


----------



## curtis (Jan 5, 2014)

Robert V said:


> Well something doesn't add up. If the garn control says you have 160 going out but your mechanical gauge says 170 coming back then something is not telling the truth. Does the garn return temp on the controller match the analog? You might just want to give it a few more burns to let all the water come up to temp. Have you done the old touch/feel the pipes trick?



The mechanical gauge is reading about  10 degrees warmer than the electric gauge on the controller. I'm going to get a couple strap-on thermometers  and see what those are reading.


----------



## sjfrench (Jan 5, 2014)

Reading your thread is like living my last month all over again.  We just fired our Garn in mid-December.  Love it.  I've got a ton to learn, but here's what I'm experiencing so far:

1.  Definitely seal that exhaust with silicone.  I missed that in the manual on the initial install and had liquid black soot slowly seeping out of the exhaust into the building.  I did the silicone it and it was fixed instantly.  It also cut back on some smoke that seemed to be infiltrating the building.  I thought it was the door because of all the puffing, but most of it was the silicone.
2.  My system was puffing like crazy.  Went back and read the manual again and I put some scrap boards at the very front entrance by the door, I just left a small gap between the door and the wood.  Solved it instantly.  Never had another problem.  I was just loading it too full, clear up next to the door entry.  The manual says we can also use a firebrick.  
3.  I now watch both the supply temp and the tank temp to determine the next burn.  For the first two weeks, I did as the earlier poster mentioned and just watched supply temp.  And then last night, I had some serious stratification taking place in the tank and didn't realize it.  The tank was in the high 180's, the supply was in the high 160's.  I knew it was going to be very cold, all four pumps were running, so loaded up and fired.  Went out this morning and the five gallon bucket I've got below the overflow valve was halfway full.  Crap.  That's the first time I've ever had water come out of that overflow, including the initial firing.  So I did a ton of reading all day during the NFL games and I've decided not to fire if the tank temp is above 175.  There is a very helpful post about the possibility of corrosion when the tank gets fired above 190 - https://www.hearth.com/talk/threads/my-garn-corrosion-fiasco-part-1.64261/  I don't think I'll be doing that again.
4.  My readings on my supply and return sensors changed instantly when I wrapped them in insulation.
5.  Some R-30 insulation goes a long way.  I super insulated the underground with sprayed in closed foam...but left some pipe exposed when I went through the crawl space under the house.  Figured it was like having radiant floor heat.  I went back and insulated those supply and return pipes and it has made a huge difference in how long my tank holds temp.


----------



## bpirger (Jan 6, 2014)

That all sounds right on course to me!   I watch primarily the supply temp in the house, since the tank temp is outside, to determine when to fire.  But I never fire unless the tank temp is down about 120.  One thing I will do, I have all radiant, is drain the heat out of the Garn until the supply is about 115 or so....then fire.  I've also come to crank up the thermostat temp while I am burning, if it is cold outside, to "supercharge" the enormous concrete slab.  The floor will get up to about 83F or so, it feels incredible when it is 0F outside, and the air temp about 74-75.  We have a lot of glass and when the temp is that cold outside, it is great.  I won't call for more heat then until 12 hours or so later, setting tstat back to 72.  I use this really only when it is very cold outside, less than 20F. 

I heat DHW as well, which is the really what determines when we fire.  I set my controller (sensor in the indirect and system controlled by Tekmar 363 is it?) for DHW at 115.  So I can reach that point when the supply is 120 or above.  Sometimes (like this evening) the DHW will run for hours if the supply is at 119, the indirect at 118, as it turns off when it reaches set point plus 4.  So quite seriously, the need for DHW will drive when I fire.  I can heat just fine down to 100-110 on the supply.  I have considered some kind of DHW "supplement" which would kick in when the supply is below 120, just to get that much more heat from a single fire, and burn a little less wood.  Though we only burn about 6 cord a year....2500 sqft, lots of glass, all radiant.  When the addition comes online (another 1000 sqft) and if ever I connect the big garage/shop (2200 sqft), all radiant slab, then my load will increase a bit. 

I also am still running my initial "non ideal" buried lines for part of the underground and I know I am losing there.  Long story....short version is when I built the house in 2001 I placed the oil boiler outside in its own shed and brought the hot water undeerground via 1" hepex wrapped with foam "pipe insulation" inside a 4" conduit.  I am STILL losing here for sure.  One of these days I have to connect the addition (still unfinished....the eternally DIYer here) to the system and will use the new 1.25" microflex buried lines.  I think that will save me considerably, perhaps as much as the load on the addition.

One thing I notice is that my high temp (the 180's right after firing) don't last very long.  Within a couple of hours I am down to the 150's.  I think that is the crappy buried lines.  But once I hit the low 150's it will persist for quite a long time.  Once I get down to the 120's....I have many hours left.  Higher temp differential, bigger loss.  For all I know my 4" conduit could be filled with water.

I wouldn't fire with anything more than 145 or so, but I also don't need the higher temps.  With the baseboard or air-water HX, and the need for higher temps, I suspect you'd have to burn sooner.  I know I always recommend the Garn for radiant but tend to dis-recommend for air HX or baseboard unless the coil or lengths of baseboard is massively over designed to work with lower temps.  It just seems to me that the system wouldn't last very long (i.e. not one fire a day) if I had to have 140 minimum water temp.  At that point, to me, one of the other boilers with storage would be likely better....I have the perception you keep those fires going longer.  More frequent feeding the monster, but more consistently higher temps.

The only place I have seen water creepage from the flue is the coverplates just below the draft motor, and only on the first fire from 70F tank or so.  After that, not again.  I did put silicon around the chimney on the rear....I believed I DID screw the insulated flue onto the flange on the rear BEFORE I built the box around the unit.  I boxed off around the pipe to hold back all the fiberglass.  Yes, it will be a pain to get access to the screws if I need to remove.

You can really tell when you need to clean your flue tubes by looking at the exhaust temps.  Generally the flue temp will be right around 500, just a touch higher.  But as time goes on, it will begin to creep up.  Time to clean.  When I cleaned this late fall, I was getting up to about 600F at the flue, as it had been about 14 months or so since I cleaned.  After cleaning, it dropped right back down to the 480-500 range.  I just use the brush and rods and spend about 15 minutes scrubbing each of the 4 lines.  I got a fair amount of soot out....maybe 4 cups total.   I shouldn't let it go so long, but was busy hanging log siding all summer. 

We do burn all year round for DHW.  In the summer, I fire about once every 4-5 days.  Household of 5, at least 7 showers a day, two loads of laundry, etc.  I will try and burn "crappy" wood then if I can, i.e. pine I drag in or similar.  "Free" DHW heat.

Puffing issues will be had when you use smaller splits, or lots of lumber scraps, or say a pile of white pine log siding scraps!  It is quite an event when it happens, as I swear it feels like the door is going to blow open.  In fact, with my too large of a load of log siding scraps, I actually had a little puffing out of the left bottom flue cover, after I cleaned it out.  Tightened the nuts a little more...no more.  I have only seen puffing a few times though....literally 3 or 4 since 2010.  Each time I knew it was likely to happen.  SO just think about what you are putting in the beast.

Regarding the firebrick in front of the air supply.  What I have noticed is that to get a clean burn, i.e. no smoke visible coming out the flue, I need to place something here to deflect some air upwards so that all the O2 isn't consumed in the firebox itself.  My wood is just under 24", limited by my splitter stroke length, so I try and build the fire aways back intot he chamber.  Then after it is going, say a few minutes into the burn when I am sure it is cranking, I will place a small chunck in front of the stack.  This really seems to clean up the burn every time.  I usually use those small end pieces that one always has laying around.  I did cut some "cookies" before about 2-3" thick when broken in half make an ideal piece for this.  They burn up of course, and I don't have to remember to pull the brick out, or not bury it, or drop wood on it, etc.

One last tidbit.  I have the sensor that the controller uses in a well and also another sensor in another controller in another well.  These two sensors will be about 10F off from each other!  I suspct it has to do with the contact of the sensor in the well....I am willing to bet one has grease and one not...etc....but i haven't really ever looked into it.  One of these days, one of the projects is to install the 32 one-wire temp sensors every where and watch what is going on.  But that will only want to make me build a system controller that I can finely tune everything!   I like the Tekmars, but I sure wish I could variable speed all my pumps to only bring in exactly what I need from othe Garn, get rid of some time delays it appears to have, etc.

All in all, we are very pleased.  I run through about 2 Mg rods a year.  Don't understand why this is since the water chemistry has been great.  Make sure you send out samples every six months to Mike at Precision.  Since 2010, I only had to put  in one bucket of stuff, about $80 or so, plus a rod every six months!  They do add up from Dectra.  Must be an electrolsys issue, but I have my pipes grounded, not sure what more I can do. 

It is quite amazing how clear the water stays inside the Garn.  Take some time and inspect it when you get your sample every six months.  I have yet to see anything that I think is a problem.  The flues and firebox will get a white scale on them, presumably from the additives,  but this is normal.  After my first flue cleaning and I looked inside, some of the scale had broken off and was floating on the surface.  That's the only thing I have seen besides clear water in this thing.

As long as there are no corrosion issues, I assume this thing will last a very long time.  Rick's issues (linked to above in another post) were related to bacteria.  On a chicken farm, I can imagine this is much more likely than in a homeowner environment.  I would be really bumming if that happened....but Rick has also stated that he feels like it was his fault for not sampling water directly from the Garn itself.   Hopefully things will continue smoothly.

For us, with radiant, I don't think there's a better way.  I only wish I had sprung for the 2000 instead of the 1500....but it is rather rare that I fire more often than 24 hours anyways....so not a real issue at all.  I do think the numbers are a little more efficient.  Must get the final exhaust temp a little lower since there is more surface area in the longer flue length (I am assuming) in the extra 500 gallon volume. 

OK, exhausts my Garn learning tidbits.  It's been bulletproof operationally....I don't think it could possibly be easier.

One more....I find that when I put the manhole cover back on, the gasket there will fall apart after just a few opening/closing.  I only look inside once every six months, but I essentially plan to replace the gasket every 12-18 months.  I have done it once...I need to do it now I think.  If you get a little opening, you will get some steam release, and your water level will drop accordingly.  Takes some time...but it will happen.  I took off the old one, used a hand grinder and sand paper to clean up the lid, and put on the new one.  Tight as can be.  Just something else to think about.

There WILL be some "sparks" and little chunks blowing out the exhaust at the rear....so keep this in mind.  Don't let the grass turn brown and dry where the exhaust goes.  Another member here with the vertical chimney has some concerns with embers blowing up and out....not sure what his final outcome was.   But if you sit outside and watch during a night burn, you will see them fly out.  The 90 into the garbage can likely will solve that issue totally as well.  My 90 usually falls off and I vent outwards....oh what a screw can do here, eh? 

Way too long.  Enjoy!  I remember my excitement/apprehension when I was looking to buy/did the installation.  Couldn't be happier at this point....our fourth heating season.   Not a drop of oil since Nov 17, 2010!


----------



## Sawyer (Jan 6, 2014)

Well said Bruce and others! Curtis, you have been given some excellent information and advice. Bruce’s firing practices and flue temperatures are the same as mine however my anode rods are still original. I see you are located in the UP, not sure how far you are from Wakefield but I am just south over the border a mile and a half.

I have the old system controller and do not have the auto shutoff. I fire when my Garn is at least below 150 degrees and preferably 130* to satisfy DHW. I heat 6,000 sq./ft of living space. I have a combination mostly radiant/HX coil system. I may add panel radiators this spring as it solve my extreme heat loss problems in the living room. If I do this the air handler would hardly run.

I have calibrated all my thermometers in boiling water; this helped some of my temperature questions. I ignore the probe in the front bung. The thermometer in the flue seems to almost match the supply temperature after the Garn is shut down for a while. I can tell weather to fire or not just by viewing it when I enter the boiler room. I use a infrared gun to check supply/return temperatures. It seems to give rather accurate readings on a black dishcloth in boiling water. I have painted sections of pipe as well as spots on the air handler to produce accurate readings with the gun. I am not as much worried about the exact temperature to a degree or two as I am knowing the same instrument is doing both measurements so the temperature differences should be accurate.


----------



## RowCropRenegade (Jan 6, 2014)

Sounds like all you guys are getting along well with your Garn.  I love mine but I absolutely HATE my house and it's use of the heat.  When it is below 15 degrees, I can only go 5-6 hours in between burns.  And that is charging the unit to 205 degrees.  You don't replace burning 2000 gals of fuel without burning some wood!


----------



## Sawyer (Jan 6, 2014)

I hear you Reed, we have warmed up to -22 at present, it will take two full burns for 24 hours. I would much rather burn 300# of wood than the equivalent in LP. I had a trouble call at 2am, -27*, when a LP furnace didn't want to burn LP either.


----------



## jebatty (Jan 7, 2014)

> I wouldn't fire [the Garn] with anything more than 145 or so, but I also don't need the higher temps. With the baseboard or air-water HX, and the need for higher temps, I suspect you'd have to burn sooner. I know I always recommend the Garn for radiant but tend to dis-recommend for air HX or baseboard unless the coil or lengths of baseboard is massively over designed to work with lower temps. It just seems to me that the system wouldn't last very long (i.e. not one fire a day) if I had to have 140 minimum water temp. At that point, to me, one of the other boilers with storage would be likely better....I have the perception you keep those fires going longer. More frequent feeding the monster, but more consistently higher temps.


This is the nemesis affecting all hot water boiler systems that require high temperature water. A gasification boiler with storage is not immune to this problem but boiler sizing and proper plumbing and system design can alleviate some of the problem. If 170F or hotter water is required, a Garn or another gasification boiler may need to burn almost continually to meet demand. The primary difference lies in how much water the boiler needs to heat before the 170F+ water is available to the system. 

With a Garn the boiler may need to heat the entire water volume before the high temperature water is available if the system is calling for heat during the burn and there is substantial mixing in the Garn during the burn. That's 1000 gallons of water and up, and that may take awhile before the hot water is available. Once the hot water is available, the hot water can be maintained by constant burning as needed, if the burn available btu's equals or exceeds demand. But there is a potential issue with a Garn that is burned continuously, and that is ash and coal buildup that at some point needs to be removed, perhaps even daily. The Garn's design is best for batch burn operations, not continuous burn, when the Garn can allow the coals to burn out and the ash removed between burns. And a batch burn operation with high demand then may result in the water volume cooling substantially below the 170F+ needed temperature.

With a gasification boiler with storage, during a burn the boiler only needs to heat the water content in the boiler to the needed temperature, a volume roughly in the 50-70 gallon range, and there may be only a small delay until this temperature is reached and the boiler is satisfying high temperature system demand. Any excess btu's not needed to meet demand can go to storage, and it is not necessary to heat the entire storage to the 170F+ water before water at that temperature is available to the system. Of course, the boiler also may need to be burned continuously to meet the high temperature demand unless its btu output exceeds demand, in which case the excess goes to storage. And  ash and coal buildup is not normally an issue with these other gasification boilers as they can be operated days and even weeks at a time without any ash removal and in my experience there is no coal buildup, and if ashes need to removed they can be removed easily with little or no interruption in the burning. A gasification boiler with storage also provides performance and advantages similar to the Garn in batch burn operation, which is how many users enjoy their systems: heat the storage up to 190F or so and then draw from storage until the boiler needs to be fired again. For gasification boilers with storage, there is flexibility is sizing the storage based on desgn need and/or space available, but storage ranging into the sizes of Garn vessel size likely would be desirable for similar boiler Btuh capacities. 

Both the Garn and other gasification boilers with storage can provide excellent low temperature service, that is, service where the need for hot water is 140F and below. Both can heat the vessel water volume/storage to a high temperature in a batch burn operation, and then satisfy demand from storage until another burn is needed. 

My direct experience is with a Garn WHS3200 (3200 gallon vessel size), a Wood Gun E500 with 4000 gallon storage, a Froling FHG-50 with 1600 gallons of storage, and a Tarm Solo Plus with 1000 gallons of storage.


----------



## curtis (Jan 7, 2014)

Well I just drained it after running the pre-cleaner and am now filling it backup with the filtered water. I found that draining with just a hose on the boiler drain I put on the bottom of the tank took forever. I ended up buying a submersible pump and using that to finish the job, well worth the $100.


----------



## RowCropRenegade (Jan 7, 2014)

Sawyer said:


> I hear you Reed, we have warmed up to -22 at present, it will take two full burns for 24 hours. I would much rather burn 300# of wood than the equivalent in LP. I had a trouble call at 2am, -27*, when a LP furnace didn't want to burn LP either.



I do burn a little LP in my vent less fireplace.  It's so cheap to burn for supplement to the Garn.  Like sunday night, -13 and wind 30 mph.  Gan was fully charged at 205 mid nite.  By 6 am, it said it was at 170 but actually supply in house was 140.  Variable rate pump was 100% and tstat was 4 below setpoint of 65.  Turned on fireplace, fired Garn.  Within 1 hour, I was back to setpoint and Garn could deliver hot enough temperature to supply house.  Maybe burned .2 gallons of LP.  Quick catch up.

I'm envious of your ability to use low water temps.  I turn a profit on the Garn project this year, so the next step is trying to tighten up this BTU black hole that is my house, lol!


----------



## sjfrench (Jan 7, 2014)

curtis said:


> I ended up buying a submersible pump and using that to finish the job, well worth the $100.



I added a second drain point to my system.  At the point where my return lines come back into the Garn, I ran 2" black pipe back to the Garn return port, and with a tee fitting on that 2" line, and ran another small section of black pipe and fitted it with a brass straight valve that I can hook a hose up to.  Of course, once the water drops below the return line, it doesn't do any good.   However, for a while it gives you at least two drain ports to speed the process.


----------



## deerhntr (Jan 10, 2014)

Curtis,

Congrats to bringing the beast online. You can gain a great deal of operational knowledge by tapping into this forum.

Just thought I would add a plot of my temps over the past week so you can see how we operate our garn. During the winter heating season, we normally burn once a day. But when the polar vortex invades PA, we stepped it up to twice. You can see from the plot below, on 1/4,1/5, and 1/6 we burnt once, and ran from ~200F down to ~150F per day. Then you can see on 1/7, 1/8, and 1/9 we burnt another small load in the morning to boost it up for the day while at work. We most likely would have been o.k. burning only once, I just wanted to be sure I didn't have to play catch-up when I got home from work.

Any way, good luck with your new system.


----------



## Sawyer (Jan 10, 2014)

I'm curious Russ, what are the double spikes at peak temps on 1-3, 6, and 7? Did you add more wood at the end of the burn?


----------



## deerhntr (Jan 10, 2014)

Sawyer said:


> I'm curious Russ, what are the double spikes at peak temps on 1-3, 6, and 7? Did you add more wood at the end of the burn?


George,

Yes, that is exactly what was going on.  The house supply sensor, in on the Heat Exchanger side of the pump, so that will show some spikes as the pump turns off and on. But the Tank sensor is in the well next to the Mechanical thermometer. That will always show a smooth plot. Looks like, do to the high demand for heat, and me being lazy, I let the burn drop almost out until I added wood again.

-Russ


----------



## Sawyer (Jan 10, 2014)

Thanks Russ, glad to see that I am not the only one that does that. I am especially vulnerable when I am burning small branch wood and trying to avoid puffing by adding in less than capacity bunches.


----------



## Robert V (Jan 12, 2014)

I know it's off topic but I just happen to see wavy air coming out of the stack of my garn this weekend. The last burn was aprox 12 hours ago so this was hot air created by a draft through the unit not normal chimney heat from the fire. I know it is a vertical unit and they recommend a damper in the inlet but I want to keep my system simple. I was thinking about some type of flapper like you find on a semi. Do you think this would restrict my flow when running by forcing the the blower to push the door open? Any other ideas?


----------



## BHetrick10 (Jan 23, 2014)

Are your guys going off the tank temp or the supply temp to make a fire.  I went off my tank temp and over shot up to 211 and had some water come out.  While this was going on my supply is 40* less. 

My supply always seems to be a min of 25  but mostly 40 degrees lower than tank. 

So that bring me to I have a 120 degree supply 160 tank and would have make a small fire and more often.  If I let the tank get to 140 my supple is only 100.  I really dont want the supply to go lower than 140.  I will be running the primary loop through a plate exchanger for the DHW and then my secondary loops are 140 for  is joist cavities and 110 in the concrete.

also I only have the garn shed insulated very. The garn only has R30 rolls of insulation on it tight together, draping over the sides.


----------



## Sawyer (Jan 23, 2014)

Your temperature spreads seem similar to mine after the Garn has been setting for a while. On mine the supply temp and thermometer on the front to the Garn will read pretty similar at the end of a burn. I fire by the supply temperature. Did you calibrate your thermometers?

If I fill my Garn to the recommended level and fire to 200 degrees I will have water run out of the overflow. It would also if I fired again and ran it up to 210 as it would expand more this time. After the initial overflow, very little comes out of the overflow below 170 degrees on mine. Above 170 there are a few drops and a little vapor. I refill mine twice a year.


----------



## BHetrick10 (Jan 23, 2014)

I am burning once every 24 hrs +/- a few depending on tank supply temp.

Didnt know sensors could be calibrated.  I do not have a sensor in the front yet.

Tonight when i lit the fire supple was only 86 tank 130.  ten min in egt was 422 supply was 113 tank 130.


----------



## Sawyer (Jan 24, 2014)

I would doubt you could calibrate the sensors and would not know how to do that if you can. I have the older style and use thermometers which can be calibrated.. My temps come together shortly after firing with the tank temperature dropping as the water mixes from the firing. Basically I ignore tank temperature. My flue temperature and supply temperature read almost identical before firing so I determine how much wood to burn based on the flue and don't even bother to go look at the supply temp anymore.

I would imagine sensor location would contribute to our temperature differences.  Can you read your flue temperature before firing? Does that match your supply temp readout?


----------



## Rick Stanley (Jan 24, 2014)

I have the same difference between tank and supply temps. As you guys say, they are equal during a burn. I don't worry about that anymore. Also there has been concern about over-firing, when to burn, at what tank temp to burn etc. Also I got worried about stack temps for awhile. After a few seasons of tinkering with different plumbing set-ups, insulating etc, I finally got it so it will heat my house YAY. Of course I heat with different temperature water depending on the weather and naturally lower water temp is better. So, when the house gets cold I build a fire.


----------



## BHetrick10 (Jan 24, 2014)

My egt will usually be lower than supply  10-20.   I assume air is traveling through exchange tubes?  I put a wad of insulation in end of exhaust after a burn to help keep that from happening.  

So am I going to have to make small fires and more of them?  

Anyone have trouble with there Controller?   My gfci died during my third burn.  On my 6th burn the fan never shut off.  The timer said  a little Over three hrs but when I checked it twelve hrs later the fan was running.  It did a great job at cooling off my whole tank.


----------



## curtis (Jan 24, 2014)

just filled my boiler and the tank temp read 145 and the supply read 115. Im going to try firing it until the supply temp is in the 180-190 range this time. I have been firing till the tank temp was in that range. Maybe now i will be getting the whole tank up to the 180-190 range.


----------



## Gasifier (Jan 24, 2014)

Congratulations! That is going to be an enjoyable unit to run.


----------



## curtis (Jan 24, 2014)

I loaded the boiler about 3/4 full with ash and after 54 minutes the supply went from 115 to 143. I did notice though that the flue is 545 degrees F. Is that too high? I've normally seen it around 450.


----------



## Sawyer (Jan 25, 2014)

Dry ash, especially splits, can still be burning pretty hot after 54 minutest, 3/4 full would be about a 2 hour burn for mine. I wouldn't worry about your 545* reading, your unit is too new to worry about cleaning the flues as long as you are burning dry wood.

I agree with Rick, after a while you start ignoring the variables between different burns and just light a fire when you want higher heat levels in the Garn. I would go by your supply temperatures.


----------



## curtis (Jan 25, 2014)

I went by my supply temp today. The supply was 183 and the tank was 198. I'm sure by doing it this way now my furnace blower won't run as long with the hotter water coming out of the garn now.


----------



## curtis (Jan 27, 2014)

Well in the last 27 days I have used almost a cord of wood to heat the house with the garn. From what I have read the wood I'm using (white ash) has a btu content of 21.6 million per cord.  So if the boiler is 80% efficient and I went 27 day on that much wood, that means I averaged roughly 27k btu an hour to heat my house. Is that right? 

Also figured that it would have taken 125 gallons of heating  oil or $500 to heat my house in last 27 days. So the $67.50 I spent on a cord of wood plus my time to cut and split it was defiantly worth it. 

And when I say cord I do mean 128 cubic feet.


----------



## Robert V (Jan 27, 2014)

curtis said:


> Well in the last 27 days I have used almost a cord of wood to heat the house with the garn. From what I have read the wood I'm using (white ash) has a btu content of 21.6 million per cord.  So if the boiler is 80% efficient and I went 27 day on that much wood, that means I averaged roughly 27k btu an hour to heat my house. Is that right?
> 
> Also figured that it would have taken 125 gallons of heating  oil or $500 to heat my house in last 27 days. So the $67.50 I spent on a cord of wood plus my time to cut and split it was defiantly worth it.
> 
> And when I say cord I do mean 128 cubic feet.


 
  Where are you in MI? That's a good price per cord. They get around $1,000 for a 10 cord semi load of oak around here.


----------



## curtis (Jan 27, 2014)

Robert V said:


> Where are you in MI? That's a good price per cord. They get around $1,000 for a 10 cord semi load of oak around here.




I am in Boyne City, I know a logger so I get a little bit of a deal but ya I pay $1350 for a 20 cord load. I think the "regular" price most pay around me is 70-75 a cord.


----------



## eauzonedan (Jan 27, 2014)

It's running about $80 a chord for a 12 cord load of red/white oak dropped +/- 20 miles no of Hayward wi. I saw some new rules on max transport distance and holding times of only weeks may be coming for mn due to gypsy moth. Between that and the lp mess it may be going up......ish!


----------



## heaterman (Jan 28, 2014)

My son Matt just got a 10 cord load of mixed hardwood, mostly oak, from Bisballe Forest Products for $750 dropped in his yard. They are just a bit north of us here. I think they deliver all over this part of the state and most of their wood has been yarded for at least a year if not two. If anyone would like their phone number shoot me a PM.


----------



## maple1 (Jan 29, 2014)

Jeebers - I might have to give up my scrounging time if I could buy wood that cheap around here.


----------



## Sawyer (Jan 29, 2014)

$90/cord for mixed maple/yellow birch over here. Lakeland Times in Minocqua had an add for $120/cord on oak, don't know if they are selling any.


----------



## curtis (Jan 29, 2014)

Ya, at 67.5 a cord it's not even worth my time to "scrounge" for wood. It's nice to have the truck come in and put it right where you want and in a nice pile.


----------



## bpirger (Feb 3, 2014)

I agree with Rick and George...after a couple of years of burning the Garn, one looks at the temp and knows to:

1.  Build a fire or not.....depending on temp outside and knowing if you will need the heat or not.  instanteous.
2.  Whether the HX is in need of cleaning.  Has it been a few months minimum and getting up in the high 500's on every burn?  Well, it would likely benefit from some scrubbing.  But, I have only done it once a year and I know I lose some efficiency.


Other than that, there really are no other decisions.  OK, time to clean out the ashes?  When you open the door, you know the answer to this instanteously as well.

For me....the only thing I don't know instanteously is my water level, as I never yet installed a site glass to allow me to check this.  But I also have learned that IF the manhole seal is nice and fresh, when I put the lid on right (about a fingertip gap evenly all around), and a little brick on top of it....then I won't lose water at all unless I overboil....and then that really only happens once.  SO again, this is a known really as well (and would be exactly with a site glass) and every 6 months when you take the water sample....you KNOW the answer to your water level....or just put more in when she is open.

The only other thing to "learn to know", for me, is the manhole gasket.   Just seems like it can't take too many manhole cycles before needing to be replaced.  Maybe 3 or 4.  Then I find it breaks/loosens in just on area, which is enough for steam to vent....and then you get a little wet insulation....and your water level becomes more unknown.  OK, so replace it every 18-24 months.  Just need to find the right stuff to stop giving Dectra $20 for a strip....though really that isn't too bad.

Oh yeah, and for me, the anodes.  Everytime I open the beast every 6 months, it is a new rod.  WIsh I knew why....and Mike keeps saying it isn't water.....has to be electrolysis.  I should look into this more....but it is grounded to the motor grounds....


----------



## Sawyer (Feb 4, 2014)

I had problems with my manhole cover leaking till I installed a 3/4" backer rod ring on the manhole. I now get no leakage. The backer rod takes out the minute voids between the seal and the manhole riser. I found if I was not getting any vapor out of the overflow tube when the temperature was 170-180 degrees that my manhole cover was leaking.


----------



## NE WOOD BURNER (Feb 4, 2014)

bpirger said:


> Oh yeah, and for me, the anodes.  Everytime I open the beast every 6 months, it is a new rod.  WIsh I knew why....and Mike keeps saying it isn't water.....has to be electrolysis.  I should look into this more....but it is grounded to the motor grounds....



I was chatting with my electrician friend about this style boiler and running the electricity to a new panel. He thought that grounding this unit properly and grounding the service with the shallow depth to SHW may create a challenge. Wonder if this is attributing to your premature anode wear?


----------



## heaterman (Feb 4, 2014)

We always bond the Garn tank itself right to the main service ground in some way or another.
Just looked at a 2000 that has been in service for 5 years and the anodes are just now beginning to look like they should be replaced at the end of this season.
Grounding and stray voltage, especially in older home can be a significant issue at times and something to be aware of on any boiler system.


----------



## NE WOOD BURNER (Feb 4, 2014)

Heaterman: is the insulation board intended to separate the boiler/tank from the corrosion present on the concrete slab? Or was the thought to just insulate the bottom?


----------



## heaterman (Feb 4, 2014)

NE WOOD BURNER said:


> Heaterman: is the insulation board intended to separate the boiler/tank from the corrosion present on the concrete slab? Or was the thought to just insulate the bottom?




Just to insulate the bottom of the Garn. A 4' wide sheet is the exact width of the skids under the Garn which are about 10" wide and run the length front to back. We've found that a 2" thick piece of standard density EPS will compress about 1/4" over time.


----------



## Sawyer (Feb 4, 2014)

heaterman said:


> We always bond the Garn tank itself right to the main service ground in some way or another.
> Just looked at a 2000 that has been in service for 5 years and the anodes are just now beginning to look like they should be replaced at the end of this season.
> Grounding and stray voltage, especially in older home can be a significant issue at times and something to be aware of on any boiler system.



My experience is similar. I have been running almost 3 1/2 years and the anodes are showing some scale but are at least 2/3rds left. I am bonded to my main service panel which is grounded to three ground rods below and outside the footings of the basement and a 90' section of 1 1/2" copper that runs from the basement to the old well pit that is 14' below ground level. I did not run a separate ground for the Garn as I figured my best potential is at the main service panel.


----------



## bpirger (Feb 4, 2014)

Here's what I have tried with the grounding.   I removed the paint from the lifting flange of the garn (on the back end) and I think drilled a hole there....or was the hole there?  No matter.  I ran an 8 AWG copper wire, bolted through that hole and connecting to the garn steel (no paint), over to the ground coming into the Garn building.  This ground is the copper wire in the 12AWG wire coming out to the building.  This line is fairly long (likely 100' or so) and goes to the main panel in the house.  At one time I also had the 8 AWG wire running to a ground rod I installed just outside the garn barn along the roof eave....where it should be fairly moist.


My main panel has a couple of ground rods driven into the ground.  I have about a foot of dirt here and then all shale....so I drove the rods as much as I could...not easy...and they are on a 45 angle as opposed to being straight down and deep.  Ground is generally wetish were the rods are as they are along the roof eave.

Whereever I have a pump installed, it's ground is tied to the ground lug on the pump housing.  I've assumed this is going to provide a ground for all the sections of copper piping I have that are "separated" from others via PEX.  My thinking is that all the copper in various "regions" (I have the Garn barn region, the outside oil boiler shed region, and the house piping region.  Each region is "insulated" via buried pex running between them...save water conduction).  Each of these sections is tied through their pump ground wire.  Each section is roughly 40' apart from the other, with the oil shed in the middle.

Is there more that I can do?  Should I run a larger dedicated wire between all the sections?  I have always wondered if my earth connection is good enough....would improving this help?  I'd think it would be about keeping all the sections at the same potential.  Perhaps relying on the 100' 12AWG connection back to the main panel is the problem?  And then another 50' length to the oil shed (with the oil boiler)?  Everything is in conduit, so I can, in theory, fish through a heavy wire.  Pull ropes are all still in place.


----------



## NE WOOD BURNER (Feb 4, 2014)

Electrolysis - results from a "noble" metal (i.e. copper, bronze, brass, etc.) in close proximity to steel (a sacrificial material). It can also result from improperly grounded equipment and/or an improperly grounded electrical service to a building. No water treatment can prevent this form of corrosion. Connect only non-galvanized steel pipe to GARN® WHS and ETS units, and install dielectric couplings where copper pipe connects to steel pipe. Sacrificial anode rods provided with your GARN® reduce the potential for this type of corrosion. If, during periodic inspection, the anode rods have decayed significantly, it is most likely a result of electrolysis.


This is from the Garn manual. I would advise to have an electrician and your Garn Rep over and go over your install. It will be a small cost to preserve your investment. It sounds to me like your main panel may not be grounded correctly and it floats around until it finds a good ground IMHO

you could post pictures of your install. there are many here with great knowledge.


----------



## Sawyer (Feb 7, 2014)

Bruce, is your neutral bonded to ground or enclosure at any point beyond your meter base or main service disconnect? Did you run three wire or 4 wire from your service disconnect to your service panel in the house. I am visualizing your power going from the house to the Garn building?


----------



## Vizsla (Feb 7, 2014)

Dielectric unions are about the worst things ever invented for the plumbing industry. They cause or fail 100% of the time.  I have never removed a Dielectric union that wasn't closed up and fully corroded inside. Whether it on a boiler,water heater or anywhere in the piping system.
However I will say, I have NEVER. Seen an electrolysis failure in the 23 years in the trade. Please don't take this the wrong way, as I am not suggesting someone circumvent the almighty "CODE".  But I have seen 200 year old farm houses with not a stitch of grounding to pipes with perfectly fine and wide open galvanized pipes. Yup, not closed up at all. I have seen hundreds of water heaters and boilers with brass or copper directly tied to steel or cast iron without a smidgen of build up, corrosion or early anode failure. If fact these are the best looking and oldest heaters I come across.  City water or well water, treated and untreated. 
I in my professional opinion, know that bonding alone accounts for the majority or all of the corrosion found in,at,or around a dielectric union. In 1 year a 3/4 DU will close to a quarter inch or less with bonding, by removing ALL bonding from the piping, or in cases where everything is pex, the corrosion is near non-existent. This is for South half of Michigan.
Electrolysis only needs millivolts to start doing its thing. And I find it suicide to use dielectrics on a Knight ,Viessman,or HTP, but some do, about as smart as bonding pex too.


----------



## bpirger (Feb 7, 2014)

George:  I have triplex running from the meter into the house panel (3 wire).  In the panel, neutral is bonded to GND via the "green screw" in the panel. At no other place does the neutral tie to GND.  I have a subpanel with 4 wires from the house panel out into the garage/addition (attached) but all power for the Garn/heating system originates from the house panel.

What if the ground and neutral were bonded out at the meter and in the house panel?  While I understand this would then require 4 wire going into the house panel (treated as a subpanel).....what is the suspicion if everything heating system originated from the house panel?  For this level of electrolysis to be occuring, I assume there has to be a potential difference between the plumbing somewhere, introducing the few mv to help force it along.  Hence my thinking that if everything is tied back to the same point, it shouldn't be a problem.  BUT, 100' long 12AWG copper will perhaps allow for some mv level differences?   But far as I know and can tell, no current should be flowing through any ground.....

Out the back of the garn, I have black iron for ~8' and then a brass ball valve and then I switch to copper.  This is on the supply and return.  We had a considerable discussion years ago here whether it was OK to go from black iron to brass to copper and it was deemed OK (and it was also deemed OK by the Garn dealer).  No copper straight to the Garn....no copper straight to the black iron.  Brass in between.   But there are no di-electric coupling adapters.

Given the rate of anode rod consumption, I am assuming there must be a problem holding everything at the same potential.....Given fairly long distances, pex isolation between segments of plumbing, I can only imagine that these potential differences are at work.

EDIT:  I just measured the potential between the plumbing/GARN and the ground coming out the Garn barn and measure 0V, down to the mV level if you believe this little meter.  It also measured 0V in the oil shed and in the house.  So, this tells me the plumbing in each of the three buildings is all tied to the ground wire that is present there.  Measuring between the different locations is a little tricky and will require so long wires/leads.

What else can I do to hunt down this problem?  If there is no potential difference between regions, this would indicate something else....but with an anode rod every 6 months, it seems unlikely.  Milke at Precision has repeatedly said it isn't the water inherently as the chemistry looks great.  I'm puzzled.


----------



## heaterman (Feb 9, 2014)

Vizsla I could not agree more on the DE unions. They are a guaranteed failure waiting to happen.


----------

