My quest for inexpensive heat.

[Markus38]

The reason I asked is because I had my basement rim joists spray foamed and it seems to have thrown off the drafting/combustion. I've had my basement window open several inches for a few days now and the boiler seems to be performing better. It looks like I may have to pipe in some external air. It's a small matter but one I need to address before the start of the next heating season.

Check the install manual page 16. there is a section about combustion air supply.

"The area of the free minimum cross-section must be 2.5 cm2 per kW of the boiler‘s nominal total output."

 

[jebatty]

Several easy ways to provide combustion air. One is the (familiar) cold air trap with an insulated flex duct terminating near the bottom of a barrel or large bucket with an open top. Cold air is trapped and combustion air flows only when there is a draw to create negative pressure.

Mine was more "elegant." I have slider windows in my shop and I wired a linear actuator to one of the sliders so that it opens the window 6" when the draft fan comes on and shuts the window when the draft fan turns off.

 

[heaterman]

When I've cleaned mine so far I've only actually cleaned the burn pot. I was looking at the owner's manual the other day where it mentioned cleaning the draft fan. Have you been doing that as part of your routine maintenance?

I clean mine only when the display tells me to, which is about every 800 hours of actual burn time.

Each time I clean it I pop the draft fan off first
Use a soft nylon bristle brush, 2" diameter down the flues to brush the dust off the scrapers mainly.
Brush off the draft "impeller" blades.
Then go to the firebox and start cleaning that from the top down.

Lift the diverter plate out of the top of the fire box and brush it off. Replace.
Brush down the sides of the firebox.
Vac out the ashes from the bottom.
Take the access plate off the second ash compartment under the flues and vacuum that area.
Brush and vacuum the firepot itself.
Remove the primary air ball and make sure there are no ashes in the air tube underneath it.
Remove the ash "suitcase" and dispose of ashes in there.
Replace everything and I'm done for another 6-8 weeks.

Since the first 2-3 tons, I do not even open the firepot door between cleanings. Just put pellets in it and let it do its thing......which it does exceedingly well.

 

[velvetfoot]

Lift the diverter plate out of the top of the fire box and brush it off. Replace.
Brush down the sides of the firebox.
Vac out the ashes from the bottom.
Take the access plate off the second ash compartment under the flues and vacuum that area.
Brush and vacuum the firepot itself.

May I ask what kind of brushes you use to do this? It's steel underneath, right?
I've never had a pellet stove but a BioWin is in my future.

 

[velvetfoot]

Markus,

Can you tell me a little more about your experience with the bulk storage, as I am thinking to do this as well? Did you assemble the bin yourself and did they deliver it? How did you pick that size? One delivery for a winter might be ideal, but that takes up a lot of space I guess. Is it dusty when they make a delivery? Does it have two pipe connections on the outside? What kind of piping goes to the bin-metal? Does the bin have to be ventilated for carbon monoxide, or is it sealed well enough? Are you thinking about humidity in the off season?

Sorry for the question blizzard, don't feel you have to answer any of them, but I'm really jazzed about the project.

 

[Markus38]

Markus,

Can you tell me a little more about your experience with the bulk storage, as I am thinking to do this as well? Did you assemble the bin yourself and did they deliver it? How did you pick that size? One delivery for a winter might be ideal, but that takes up a lot of space I guess. Is it dusty when they make a delivery? Does it have two pipe connections on the outside? What kind of piping goes to the bin-metal? Does the bin have to be ventilated for carbon monoxide, or is it sealed well enough? Are you thinking about humidity in the off season?

Sorry for the question blizzard, don't feel you have to answer any of them, but I'm really jazzed about the project.

Hello Velvetfoot,

Ask as many questions as you want. I love talking about my boiler!

During the planning phase, I estimated my usage at 10 -12 ton a year and I wanted to fill the storage no more than 3 to 4 times a year. Also the wife nixed the outdoor silo (a single filling per year would be amazing). I bought the 4 ton storage hopper from Vermont Renewable Fuels. They delivered it but I assembled it. It is large, bulky and quiet heavy but I still assembled it by myself. It may be wise to get some help with the assembly. I used silicone in all the joints to reduce the dust. The hopper itself has a pellet inlet and an air outlet. The bulk delivery guys hook up to these lines, so they are pulling air from your hopper as well as blowing pellets into the hopper. I do not have them piped to the outside. I fill the hopper through garage door. The filling process is a bit dusty, my hopper is in my garage so the dust and CO is not that much of a bother (too many holes for CO build-up). There is also a vent with a filter sock to let the hopper breath. I believe the vent is for not allowing a vacuum during pellet conveying to the boiler not as a CO vent. Also as a safety precaution the Biowin does a burnout before it conveys the pellets, so it will not push combustion gasses from the boiler into the hopper. I did put a CO detector by the vent as a safety precaution though. I think the bigger problem is the hopper is confined space, so it will naturally collect heavier gas (CO2, CO). So if you have the urge to go into the hopper to clean out the fines, please make sure you have enough oxygen to breath. The other considerations are you should have a “straight shot” as much as possible from your storage hopper to your boiler. I mean that the less elbows the better. Also all turns should be wide as possible. The tighter the turns the harder the blower has to work and the pellets will get beat up. Also all tubing for pneumatic conveying needs to be special static charge dissipating and properly grounded to avoid a dust explosion. Also double check with conveyer system, it will have limits as to how far away and how much of a change in elevation you can get the pellets from the boiler.

Sorry about the long answer but I am still jazzed up about the boiler

 

[velvetfoot]

Great answers, thanks!

 

[velvetfoot]

Markus,

Did the place you got the hopper from, Vermont Renewables ?, modify the bottom of the hopper for the vacuum pickup, vs. an auger? It looks like there's a box on the bottom rather than more cone shaped, but it's hard to tell from VR's web site. Did you have to cut a hole in the metal and how did you protect the hose from the sharp edges and seal it. Thanks.

VF

 

[Markus38]

Markus,

Did the place you got the hopper from, Vermont Renewables ?, modify the bottom of the hopper for the vacuum pickup, vs. an auger? It looks like there's a box on the bottom rather than more cone shaped, but it's hard to tell from VR's web site. Did you have to cut a hole in the metal and how did you protect the hose from the sharp edges and seal it. Thanks.

VF

The bottom of my hopper is a box. I can't recall if they had different options. The only modifications were 2 holes for the tubing and 4 holes to secure the probe in the center of the box. I used a hole saw to cut two tubing holes. I used car door edge U-molding to protect the tubing. I was told that the molding maybe a bit over kill but that did not stop me. I then used silicone to seal between the tubing and the U-molding.

 

[chken]

Hello Velvetfoot,

Ask as many questions as you want. I love talking about my boiler!

During the planning phase, I estimated my usage at 10 -12 ton a year and I wanted to fill the storage no more than 3 to 4 times a year. Also the wife nixed the outdoor silo (a single filling per year would be amazing)....

Sorry about the long answer but I am still jazzed up about the boiler

Now you have me thinking about an outdoor silo! I estimate I could use 10 tons and where I would put my fill nozzles is just a tad over 80ft from the road, which means my local bulk delivery may not be able to reach. Plus, what's doable in the Summer, may be 10x harder to reach in Winter, so the silo idea looks interesting as I can place that closer to the road, and fill it once when the weather's nice, and not have to think about it until the next year. My neighbor may not like it, but then he shouldn't have built his house so close to mine! Heck, I wonder if I can adapt it to put a treehouse on top for the kids?

 

[PassionForFire&Water]

These are some pros and cons for a silo used with a pellet boiler for residential use: say less then 30 kW or 102,000 BTU/hr.

Cons:
- cost is 2x the cost of an indoor storage room
- no redundancy in suction point. Most silos have 1 probe at the bottom.
- if pellets are stacked higher then 8', they have more tendency to bridge because of the pressure.
- your money is no longer in your pocket when you buy 10 tons at once versus 2 or 3 smaller deliveries.
- right now there is no real incentive to buy bulk pellets. You would think bulk is cheaper, but it's not
- when you have a mild winter, you will sit on a lot of pellets for 1 more summer that can pickup moisture

Pros:
- you save valuable inside space.
- you keep the possible mess outside from the pellet dust during delivery.
- lower pellet delivery fee
- you may be able to take advantage of lower pellet pricing when buying early.

In my opinion, a pellet storage room should be build so you have 2, maximum 3 deliveries per year.

 

[velvetfoot]

In the interest of not taking this great install thread too far awry, and that the subject of pellet storage is worth its own thread, I'm gonna start one. Whether anyone replies, well, who knows.

 

[PassionForFire&Water]

In the interest of not taking this great install thread too far awry, and that the subject of pellet storage is worth its own thread, I'm gonna start one. Whether anyone replies, well, who knows.

Great idea !

 

[velvetfoot]

Markus, would you have a piping schematic? I am interested in how you tied in the oil boiler and if it comes on automatically when the pellet boiler shuts down.
Thanks.

 

[AK13]

OP, I might have missed it, but are you getting bulk pellet deliveries? And if so what company do you use and do you have any other details on their set-up (what size truck they are using, etc)?

Also, I would strongly recommend using pellets for DHW in the summer. Why on earth would you burn expensive oil when you have just invested so much in your pellet system? You have storage so you should be able to run a "full burn" off of your pellet system so you won't see any loss of efficiency by using it for your DHW load. I would still fire up the oil once a year, but why use it all summer long?

 

[velvetfoot]

Speaking for myself, I might get a heat pump wh for the dehumidification. Maybe the pellets won't go mushy then.

 

[DBNH22]

Speaking for myself, I might get a heat pump wh for the dehumidification. Maybe the pellets won't go mushy then.

I am looking into the NYLE HPWH myself. There are a few on this site that own them and have spoken about them.

 

[Markus38]

Markus, would you have a piping schematic? I am interested in how you tied in the oil boiler and if it comes on automatically when the pellet boiler shuts down.
Thanks.

My plumber ran the two in parallel before I could say anything. After I gave it some thought I decided to stick with it in parallel because my oil boiler is old and not properly insulated, I would loose too much heat out the boiler. When the time comes to upgrade my backup boiler I may put them in series.

OP, I might have missed it, but are you getting bulk pellet deliveries? And if so what company do you use and do you have any other details on their set-up (what size truck they are using, etc)?

Also, I would strongly recommend using pellets for DHW in the summer. Why on earth would you burn expensive oil when you have just invested so much in your pellet system? You have storage so you should be able to run a "full burn" off of your pellet system so you won't see any loss of efficiency by using it for your DHW load. I would still fire up the oil once a year, but why use it all summer long?

Have not totally figured out the summer DHW yet. I may just may run out my pellets in the hopper then switch to oil. I am still siting a ton of pellets in the hopper and 500 gallons of oil so I have a few options. I have been taking weekly pellet usage readings so I will be able to figure how much water is going to cost me with the pellet boiler. But your point is inconsideration, an "inefficient" pellet boiler may still beat my old oil boiler. I will determine what use when I get the spread sheet filled in for this year.
I am getting bulk deliveries but I am hauling them with my truck 50 bags at a time. The current bulk delivery guys are far from me and the delivery would add too much to over all cost. Right now I can deal with the extra work for the extra savings. When the bulk guys are closer/ cheaper I would happily switch over

 

[velvetfoot]

How are you getting the pellets into the hopper? Are you blowing them in?

 

[Markus38]

How are you getting the pellets into the hopper? Are you blowing them in?

This solution is a bit dangerous, so please be advised to use static dissipating parts and also properly ground everything. Also check grounding yearly. That all said.

I used a leaf blower, PVC Pipe and some muffler parts to make a venturi conveyer. Built a little hopper with the crate the biowin came in and put the venturi on the bottom of that hopper. The venturi slowly trickles the pellets into the path of the leaf blower then gets shot into the steel hopper. I needed to use a rigid pipe to move the pellets because the pellets got stuck in flexible tubing. I used a 4 inch flexible dust collection hose to connect inlet of the leaf blower to the hopper. Sucking the air from the hopper helps the blowing of the pellets into the hopper.

It is work in progress I just had an idea and kept on McGyvering it until it worked. I do not have an internal picture of what I made but I found a similar picture. It is hard to explain. I used a 2” by 18” long muffler for the nozzle and a 3.5”to 2.5”muffler reducer as the diffuser in the picture. I mounted it all in a PVC Tee. I had to use shims to center everything. The nozzle has to be in the center of the diffuser and the distance from the nozzle tip to the diffuser needs adjusting to get it right. All in all it works but it is a bit slow. I just load in a few bags go do some stuff then return and fill some more bags. The good thing is I save my back and get the big hopper filled to the top.

 

[velvetfoot]

There was someone who rigged up something similar and posted a video (I forget now who), but no offense, I think it worked better. he had no complaint about it going slow.

 

[Markus38]

There was someone who rigged up something similar and posted a video (I forget now who), but no offense, I think it worked better. he had no complaint about it going slow.

Point taken, I am my own worst critic. There is a few short comings in the design, I think I have to go a 2 -2.5 inch pellet pipe to increase the speed of the pellets. I also have to get the pellets up 7 ft, this is what really slows everything up. It works so I haven't fixed it but maybe I will fiddle with it over the summer.

 

[velvetfoot]

I was thinking of this:
https://www.hearth.com/talk/threads/blowing-pellets-with-a-leaf-blower.89327/#post-1163502

The 7 feet could put a damper on things.

 

[Markus38]

I was thinking of this:
https://www.hearth.com/talk/threads/blowing-pellets-with-a-leaf-blower.89327/#post-1163502

The 7 feet could put a damper on things.

Thanks I saw after you mentioned it. It got the wheels a turning I would also like something I could pack away during the summer.

 

[AndrewChurchill]

How much does your pellet blower hold?

This solution is a bit dangerous, so please be advised to use static dissipating parts and also properly ground everything. Also check grounding yearly. That all said.

I used a leaf blower, PVC Pipe and some muffler parts to make a venturi conveyer. Built a little hopper with the crate the biowin came in and put the venturi on the bottom of that hopper. The venturi slowly trickles the pellets into the path of the leaf blower then gets shot into the steel hopper. I needed to use a rigid pipe to move the pellets because the pellets got stuck in flexible tubing. I used a 4 inch flexible dust collection hose to connect inlet of the leaf blower to the hopper. Sucking the air from the hopper helps the blowing of the pellets into the hopper.

It is work in progress I just had an idea and kept on McGyvering it until it worked. I do not have an internal picture of what I made but I found a similar picture. It is hard to explain. I used a 2” by 18” long muffler for the nozzle and a 3.5”to 2.5”muffler reducer as the diffuser in the picture. I mounted it all in a PVC Tee. I had to use shims to center everything. The nozzle has to be in the center of the diffuser and the distance from the nozzle tip to the diffuser needs adjusting to get it right. All in all it works but it is a bit slow. I just load in a few bags go do some stuff then return and fill some more bags. The good thing is I save my back and get the big hopper filled to the top.