Tarm 3rd Week of Use:Notes and Improvements

[garysec]

Actually I have 2 different overheat protections, 1 from over firing and 1 for power outage. My boiler overheat with power will (well is suppose to) open my main Taco zone valve and turns on the circulator at the OB to supply heat to that zone. My power outage protection is a dudad (don't know what it is called), that opens a seperate 3/4 inch line at the WB that is tied in and gravity flows to my main zone on the other side of that Taco zone valve. My 2 boilers are 35 feet apart so I have long copper runs between boilers, 1 1/4" for the main run and the 3/4" for the power outage run. But you are correct I really should test to make sure they work.

 

[beantaxi]

I had a similar event last pm....to the issue of continued burn times...have been doing better with all temps flue and boiler with smaller splits...2-4 inch pieces..and then maybe one larger round in the middle top or even another larger split up to 6 inch....anyway last pm had fire going very well flue 500 boiler 160 or so down to coals and needing new load, which I did...reestablished new load and closed up ...off duty from 12 30 am until 530 am..at 530am boiler fan was off and boiler temps down to 107 or so??? Why was fan off? shouldn't it hold boiler at 140+ and have fan kick back in if demand is low but fire is going good?? It appears to me that it must have been overheat....but could not tell that dump zone was being utilized. I have seen my dump zone operate but do not recall if I ended up having to hit reset....I do not belive I did...so how did that happen? Is this just a matter of proper amount of wood load based upon experience of demand and use or is it in the controls somewhere? I have fan set to full and lo-limit set to 60 Cent.....Maybe fan should be set to lower 180 or so limit so overheat doesn't happen? Any advice appreciated as always ...wish I could offer someone some help but still learning this thing....for anyone out there who has larger splits, and is splitting by hand....I suggest a great solution to that is a Ryobi electric 4 ton splitter that cost $ 299 at Home Depot is worth every penny!! Works great splitting 6-10 inch quarters down to 2-4 inch splits....I keep some larger pieces for the overnight load...to leave coals for AM....but have still not got this down to a science...I was splitting by hand...major wear and tear takien off by the electric splitter.....Thanks to All ....

 

[garysec]

If you find out what temp that kicks off on let me know. I turned my fan down a little so I would stay around 185 so maybe it wouldn't happen again until I'm sure my overheat zone is working which I need to test.

I like the idea of the electric splitter, I may have to look into one of those, I do have some I should split again although right now I seem to be able to maintain pretty good temps but constantly picking thru the pile looking for smaller ones to add.

 

[beantaxi]

The installer says Tarm said that because I do not have storage actually hooked but ready (piped for it already that may be why the shutdown took place...however that does not seem right to me...my only thought is power went off (blipped) without my knowledge...that has happened around here...power is a definite issue...anyway I would otherwise think that maybe the dump zone was not taking on heat fast enough and the fan got killed from that ...I know the fire was rippin when I left it and boiler could have hit overheat...but I thought that would just kick in the dump zone...I have 24ft baseboard fin above the level of the boiler...and the dump overheat also goes to a radiant in concrete slab zone....I am still trying to find out what actually happened...this afternoon I did the same...fire was good, boiler temps around 150 or so I loaded up, came back an hour later and the fan was off(however the light was on so it was not tripped like last evening)...and I am about to go check to see if the fan has come back on...the baseboard dump was taking heat as was the radiant slab zone ...this is the way I expected it to be...if boiler gets over temp fan kicks off and dump begins until boiler temp drops and then after reaching a certain level ( I do not know what that should be but I would hope not much less than 140) that the fan would kick back on and restart everything.....anyway will keep trying to figure what actually happened and post it if I ever figure it out....as to electric splitter ..it is the best 300 I ever spent...for knocking off bigg slits down to small ones.....home depot has it check the web site Ryobi 4 ton model $ 299.00.....sounds like I am an advertisement ...but when something works well and saves time and energy it should be touted! ..I will update my most recent fan kickoff (but still activeated...in other words I did not have to hit reset switch: YET) ....be back at you later..Thanks

 

[jebatty]

I believe that the Tarm overheat control setting is 210F. I don't know whether this is adjustable. Your idea of turning down the hi-limit is worth a try. I suspect that a couple of factors are occurring at the same time. 1) you are in high burn, supplying heat to zones, and then all zones go off. A lot of heat is still being generated with no relief. Hi-limit shuts down draft fan but heat continues to build until overheat is tripped. 2) you have a high draft chimney that continues to draw air through the draft fan opening, maintaining a low burn even though the draft fan is off. This situation is normal to some small extent, but you may be experiencing unusual continuing draw of air. 3) you have an air leak around one of the doors which is allowing the burn to continue, even though the draft is off. This you should be able to identify by trying to pull a piece of paper through the closed door gasket. If it slips through fairly easily anywhere, there likely is an air leak. 4) If you have the old style Tarm and you nwere supposed to seal the door frames to the boiler and sheet metal frame to the door frames, and you didn't do that or got a bad seal, it might be possible to have an air leak aroud the door frame where the seal is poor or missing.

Suggestion: Bring the boiler just about up to the point when the hi-limit will shut the draft fan off, with the firebox about 1/2 full, add some fresh dry wood (which will result in a fairly intense burn), and let the burn go and see what happens. The hi-limit should shut the draft fan off. Watch what happens to the boiler temperature and see how high it continues to rise. If it rises to overheat, see what happens. Is the overheat loop activated? If the boiler goes to overheat, it needs to cool down (I think) to 140 before you can do a re-set. Also, when the hi-limit shuts the draft fan down, observe the extent of continuing "gasifying" burn through the viewing port. There will be some which will continue for awhile, that is normal, but watch how long and intense your's continues. Also observe the probe flue temp reading when the h-limit shuts the draft fan off. If it is at 500 when hi-limit shuts down the draft fan, you should see the temp starting to drop fairly soon and continuing to drop to about 100. If it does not drop, or stays close to 500 for quite awhile, you have a burn continuing. Air is getting in somewhere to keep that burn going.

Talk to Tarm with whatever data you have. Let us know what you find.

 

[jebatty]

Observation and then a further suggestion.

I was observing my Tarm this morning, draft fan cycled off at about 190-195, temp rose to 200 before starting to fall. I have storage, with incoming water through a plate hx at 140 at the time, circs running so heat was continually being drawn off the boiler. Temp started to drop from 200 within a couple of minutes. I suspect it could have gone into overheat if I had not been drawing heat off the boiler.

If you have storage, I suspect you do not experience overheat except perhaps when the tank is up to max heat. If you do not have storage, you might want to consider a buffer tank (small storage tank) to take the excess heat when your system is not demanding heat. A new or used hot water tank should work well for this, and I think electric ones are less expensive than gas. No need to wire it up.

 

[Paso]

What caused page 2 of this post require using the slide bar to read the page???

 

[garysec]

I haven't seen mine get that high yet although I'm not running my fan at max. Currently have it set so it goes off probably about 185, might push up close to 190 after.
As far as an air leak I think mine is pretty tight. When the fan is running my flue temp runs around 550 and within minutes after the fan goes off I'm down below 200.
Not long after that my flue is pretty much cool. Last night to check my over heat with power I just turned down my aguastat to 180 with no current call for heat on my overheat dump zone
and my zone valved open and circulator came on, so that seemed to work. It was set for 210, I backed it off to 200 for now.
I don't think I've got much of a load on my system right now but hoping to get my DHW hooked up and I also have a Modine in the basement I'm going to put on a zone although my
basement has gone up 5 degrees with all the copper runs I have now.

 

[beantaxi]

Hi to all..I have not had to reset the system switch in the last few days...I have decided that it would be a good idea to try to keep the boiler from hitting the 200 degree dump zone initiation...by adjusting the high temp limit knob...(I must have one of the newest units delivered in late November)...the fan is one speed only and is not speed adjustable)...the high limit adj can be set back to kick off the fan at say 182 or so (this dial has no numbers on it so you have to get the boiler up over 185 and slowly dial it down ....note when the fan kicks back off...and leave the knob there) that should set high limit around 185 or so....so now the fan will kick off when boiler reaches 185 preventing the dump at 200 and when the boiler drops 20 degrees or so it will kick the fan back on, cycling on and off as needed...my other issue, was not understanding that the low limit boiler at 140 (60 c on low limit dial) kicks the fan off when the boiler dropped as low as 140...I see no reason to kick the fans off when the boiler dropped to 140..I have always had good coals and wood for a few more hours burn in the box but since the fan kicked off when boiler reached 140 the fuel went into suspend and boiler continued to cool down..not good ...my radiant floor heat can work on 120 degrees just fine, so I do not want the fan kciking off and fire in suspend and not ever kicking back in...so I set lo limit way down ro 30 C...this should keep fan going until fire and fuel is used or I intervene to add more fuel whichever comes first....do not know if anyone else has had this problem...may be an issue only with radiant floor hot water heat systems...but if you do not want the fire to start going out when boiler is still at 140...set down lo limit dial ...way down...that should do it...most of my issues should be resolved when storage tank is installed at least according to Tarm and the installer....

 

[nporter]

..my other issue, was not understanding that the low limit boiler at 140 (60 c on low limit dial) kicks the fan off when the boiler dropped as low as 140...I see no reason to kick the fans off when the boiler dropped to 140..I have always had good coals and wood for a few more hours burn in the box but since the fan kicked off when boiler reached 140 the fuel went into suspend and boiler continued to cool down..not good ...my radiant floor heat can work on 120 degrees just fine, so I do not want the fan kciking off and fire in suspend and not ever kicking back in...so I set lo limit way down ro 30 C...this should keep fan going until fire and fuel is used or I intervene to add more fuel whichever comes first..

I am having issues with my fan just shutting off on the middle of a burn for no apparent reason. This might help get that issue resolved for me. Your reasoning makes good sense to me with setting the lo limit thermostat at 30°C. The number scale on my dial starts at 50°C and goes up to ~300°.

Does yours and if so did you just estimate the distance past the 50°C mark and does this setting seem to be working for you?

 

[beantaxi]

Yes Porter, mine has the same dial ...starts at 50 C and goes up from there....I just estimated the distance between zero and 50 to get around 30C...this does seem to have helped ....remember that the fan will shut off upon reaching your upper limit on the other dial if all the way up I believe that is 194 F....but that is so close to my 200 dump zone initialization that the dump activation stopped the fan...and the fan was inactivated at that point I believe....it appears that if the fan has cut off (but the light is still on) that this means you hit the high limit and the unit is cycling on and off as it should..the key being that the unit should come back on after a drop of around 20 F on your thermostat...hope this helps....

 

[rcollman]

Also remember to clean the hx tubes. I've been cleaning mine about every two weeks, but when you notice the flue probe thermometer starting to rise above "normal," that's a good sign that brushing the hx tubes is in order.

I came home from Xmas in MI and the Solo40 was cold, so I decided to clean the tubes for the first time (RT 3 million BTUs). Just enough head room with the bendable wire brush. Definitely some dust and materials that did not easily brush out. The tubes now look slightly rough. I don't have a flue probe (I think I don't have one) and I am wondering if that is another item to get or should I clean it after every 3 mil BTUs?. Opinions welcome.

Does anyone agree with setting low limit to 60 Centigrade (without storage) and regarding the bridging issues I see people saying reducing fan speeds help.....the fan seems to go off on my unit if I move it counter clockwise....does not just “slow” down..anyone know why?

I have two external control dials. I wish the top had some sort of calibrated markings instead of the spiral. I slapped a piece of tape on it. Now have a pencil mark I line up with a hex screw on the front panel. That sets the max temp to 175 degrees.

The bottom one is usually set to 60 to 70 C. If I know there is not going to be much demand for heat and the fire will be out in the early AM, why make the blower work for nothing? But I would listen to Jim because I am still learning.

To me a good wood load procedure, small splits, like described above, just about eliminates bridging.

We had some serious cold after my return. Decided to split wood so all wood would fit through a 4 inch circle. I have run 1.1 million BTU of wood split this way. It burns up, no major charred logs left over (plus and minus). Settles down near the slit without poking.

I always leave the high limit set all the way up. I would set this at the point where you want maximum boiler hot water to be and then leave the high limit control setting alone. There is no reason to adjust this after you have the setting you want.

OK, educate me. Why do you set it so high? Because you have storage? I thought some relief valve would blow, so I get worried when it approaches 200.

I will post with my next level question about the flame in my combustion chamber. Thanks to everyone and Happy New Year!

Chris

 

[jebatty]

If you are still getting usable heat with the lo-limit set below 140, go ahead. For me, with storage, at boiler 140 I often will have bottom of tank above 140, so no additional heat is being provided by the boiler. My tank in effect is heating the boler. Time to shut it off.

OK, educate me. Why do you set it so high? Because you have storage? I thought some relief valve would blow, so I get worried when it approaches 200.

I do set the hi-limit at the max because I have storage. My tank will take everything the boiler can put out. Relief valve blows at 30 psi, my boiler at 200F has pressure of only about 20 psi, and 200F is the maximum the boiler reaches with hi-limit set at the max.

 

[beantaxi]

JIM..CAN YOU TELL US WITH THE STORAGE, I THOUGHT YOU SAID SOMEWHERE YOU HAD 1000GAL...ANYWAY CAN YOU TELL US HOW LONG THAT NUMBER OF GALLONS LASTS YOU? i AM SCHEDULING 880 GAL STORAGE TANKS...TO BE SET AT 140 f AS LIMIT...AND WAS WONDERING HOW MANY CYCLES OF BURNING WOULD CHARGE IT AND HOW LONG IT MAY LAST...THE LOW LIMIT SETTING AT BELOW 140 TO KEEP FAN ON IS ONLY WHILE I HAVE NO STORAGE ON LINE.....BUT IT IS WORKING WELL NOW UNTIL i GET STORAGE ON LINE....I HAVE BEEN ABLE TO KEEP FIRE GOING BETTER WITH THE REDUCED LOW LIMIT SO FAN STAYS ON UNTIL INTERVENE...THANKS

 

[gorsuchmill]

I, too, have had some issues with the fan shutting off while wood is still available in the loading chamber. I spoke with Rene at Tarm and it seems my issue may be the result of setting back my thermostats during the day when noone is home. My "at home" temp is set to 64* and away is at 58*. On milder days, when the house doesn't lose heat so quickly, the temperature set back results in none of my zones calling for heat during an extended period of time. As a result, the hot water in the boiler simply circulates within the Tarm, which results in the water temp staying high for a long period of time, which, in turn, keeps the fan off. At some point, the coals simply burn out, such that when the water temp finally drops, and the fan kicks on, the boiler is tricked into thinking it is out of fuel. To remedy this, I'm going to keep one of my zones at a higher temp during the day, with the hope that the more frequent calls for heat will keep the coals alive and kicking. I'll keep you posted.

 

[jebatty]

...CAN YOU TELL US WITH THE STORAGE, I THOUGHT YOU SAID SOMEWHERE YOU HAD 1000GAL...ANYWAY CAN YOU TELL US HOW LONG THAT NUMBER OF GALLONS LASTS YOU?

It's better not to use CAPS in you posts as they are hard to read.

My situation is a little unique because I'm heating my shop, the Tarm is installed in the shop, and I use the tank (partially insulated) as a radiator to heat the shop, with a unit heater also available if a heat boost is needed. That said, the shop is an old barn, 10' ceilings, leakier than a sieve to the outside, poorly insulated, and it is cold where I live (18 nights below 0 during December). During this winter cold, I usually have one nearly continuous burn per day of about 6 hours, so heat transferred to the storage is supplying most of the heat need. As temperatures moderate, I will burn as infrequently as every other to every 4-5th day. I'm not heating dhw.

I was visiting family last week, leaving on a Wed afternoon and returned the following Wed afternoon. During this period night lows reached -24F and were below 0 four nights. I heated the tank to 165 before leaving, no other heat in the shop. When I returned top of tank was 60 and the shop was 34.

How long it will take you to charge your 880 gal tank and how long it will last will depend on your heat demands, which is related to lots of factors, and my northern MN heat demands are pretty extreme.

Off hand I would think you would want to load storage up to 160-180 or so, let the boiler burn full out until this is reached, then let the boiler go out, and then use mixing valves to deliver the heat you need depending on your baseboard or radiant setup.

Gasification boilers seem to work best and most efficiently when they can burn full out, with as little idling as possible, rather than stopping and starting with lots of idling. Each idle cycle adds some inefficiency, especially if the idle periods are longer than about 15-30 minutes. Storage allows that full out burn with none to very short idle periods because you have a place to store the heat not immediately needed.

 

[beantaxi]

Sorry about the caps.....Thanks Jim....I guess every situation is different but all evidence of what people are running into is educational...I have a 2000 Sf three story building with radiant 3 zone system and with DHW as another zone, the Tarm Solo 40 is currently supplying all heat and DHW (without the storage which should be on line in a week or two)..I have been running 24/7 burn cycles adding wood every three hours or so.....I have the luxury of being able to work from home so I can do this for now, hoping storage will alleviate the number of burn cycles and soak up enough heat that it would require only one or two burn cycles a day, is there anyone out there running the Tarm for all heat and DHW and with storage in place, just wondering if I might expect to get down to one or two burn cycles a day with the storage?...As to the shutoff of the unit, mine was shutting off [fan shut off]at 140 which seemed to leave plenty of wood in the firebox and not use it...when I set the low level therm down to 30 C it has kept the fan on until I need to add wood, usually in three to 3 1/2 hours (box not jam pack loaded, say 12 small splits 2-4") and may be one round 4" in the top of the load)...I can sink any extra heat into the concrete slab in the basement for more storage, which has been helping the efficiency of this thing...I feel like right now I may be getting about one week 24/7 burning out of a face cord (pretty cold here ave in teens to 20's...last night -10).....seems pretty good to me any one else have the Tarm Solo 40 in similar circumstances...if so what kind of wood use are you getting...Thanks to all...especially you Jim....you have been very helpful and I know these answers take some time to do...