Pellet Stoves & Furnace Filters

[Lindsay]

I installed a Pelpro pellet stove in the fall, locating it in the basement, near the stairwell to the main floor of my 2000 sq ft bungalow and also near the main cold air return in the basement. I set my propane furnace to off and the furnace fan to Circulate. I’m very happy with the heat and distribution .... maintaining 74F in the basement and 72F on the main floor. I’m going through about 1.5 bags of softwood pellets per day. I clean out the stove every day and then every month i give a thorough cleaning which includes using an old leaf blower to suck ash out from the end of my stove pipe outside. So far .... very happy BUT I’m wondering about my furnace filters. I change the filter every month and they are BLACK!! What is up with that? I would appreciate anyone’s thoughts on this as I’m beginning to wonder if it is safe for me to be breathing all those particulants. BTW ... I’m using the top end furnace filter from Canada Filters. Thoughts??? Thanks!!

 

[zrock]

My first thought is your furnace is creating a positive/negative pressure in the house causing it to pull fine ash from the stove. Is their a oak installed on the stove? Is your furnace blower running on Max speed? you have a way to adjust the speed some furnaces have a switch on the inside to lower fan speed for people that use it to circulate air.

 

[maple1]

Ya, furnace could be sucking dirties from the stove. Maybe.

I take it that the filter is a lot dirtier than it normally would be when running it on propane? That's the only reason I can think of if the pellet stove is the only difference. Which would also raise concern about it possibly pulling CO2.

 

[Lindsay]

My first thought is your furnace is creating a positive/negative pressure in the house causing it to pull fine ash from the stove. Is their a oak installed on the stove? Is your furnace blower running on Max speed? you have a way to adjust the speed some furnaces have a switch on the inside to lower fan speed for people that use it to circulate air.

WOW! That was fast! Thank you very much for responding so quickly. The Pelpro does not have a choke (I assume that’s what you were asking). It’s a basic plain jane pellet stove from Home Depot. I’ve a walk out basement so the exhaust goes up vertically for 5-6 feet and then out through the basement wall and extends some 40+ inches. All in code. The house is 6 years old and has an air exchanger that keeps fresh air coming into the house and the humidity level at 40%. When the furnace, which is set to “circulate” comes on, the fan speed is identical to when I would use propane to heat the house. I have a large 4’ ceiling fan near the top of the stairwell in a cathedral ceiling that draws heat up, plus smaller ceiling fans in the studio and master bedroom (a long way from the stairwell) which also draws air. Do you think the air exchanger may be the culprit?

 

[maple1]

Do you have a CO2 detector?

 

[Lindsay]

Ya, furnace could be sucking dirties from the stove. Maybe.

I take it that the filter is a lot dirtier than it normally would be when running it on propane? That's the only reason I can think of if the pellet stove is the only difference. Which would also raise concern about it possibly pulling CO2.

Thank you for repsonding! Yes, my filter is a LOT dirtier with the pellet stove. I have several ceiling alarm systems in the house but am unsure of their capabilities. Thank you - I will check them all.

The joint between the “chimney” and the stove is well sealed with metallic tape but the individual joints on the chimney are not taped - should they be?

 

[Lindsay]

Do you have a CO2 detector?

I’m going to check. I noticed you mention you don’t use fans .... how do you distribute the heat? Our bungalow is 60’ long ...... open concept but still that’s a long way to pull air.

 

[zrock]

I was speaking of OAK = outside air intake not choke. Could be a possibility with the stove running and not having a fresh air intake from outside it is drafting fresh air from your furnace air intake drawing all the air through your vents and back through the filter. Along with that its pulling all the fine dust in your heating system back through the filter. As well its probably pulling fines from every nook and cranny in your home since its creating a negative pressure and lots of drafts..

to the post above he uses his fan in his heating system to circulate air

 

[maple1]

I’m going to check. I noticed you mention you don’t use fans .... how do you distribute the heat? Our bungalow is 60’ long ...... open concept but still that’s a long way to pull air.

I don't have a pellet stove. Boiler.

But with all those fans running pulling air from where your stove is, and the filter issue description, I would be quite concerned you could be pulling CO2 from your pellet stove, into your house. Which could be deadly.

 

[Watcher1]

I installed a Pelpro pellet stove in the fall, locating it in the basement, near the stairwell to the main floor of my 2000 sq ft bungalow and also near the main cold air return in the basement. I set my propane furnace to off and the furnace fan to Circulate. I’m very happy with the heat and distribution .... maintaining 74F in the basement and 72F on the main floor. I’m going through about 1.5 bags of softwood pellets per day. I clean out the stove every day and then every month i give a thorough cleaning which includes using an old leaf blower to suck ash out from the end of my stove pipe outside. So far .... very happy BUT I’m wondering about my furnace filters. I change the filter every month and they are BLACK!! What is up with that? I would appreciate anyone’s thoughts on this as I’m beginning to wonder if it is safe for me to be breathing all those particulants. BTW ... I’m using the top end furnace filter from Canada Filters. Thoughts??? Thanks!!

So just some things to consider check for: I had a Baby Magnum pellet corn stove, the seal on the bottom of the auger went out and so fine sawdust from the pellets work their way thru and then they were picked up by the room air fan intake and then sent thru the heat exchanger. One day we noticed this black crap on the freezer in the basement and also it was getting on and sticking everywhere. Took some time to figure out what was going on. Point of story open up the back of your stove and look for the sawdust. Next, if you are running your furnace fan a lot you should have the OAK set up on your stove. 2 reasons, 1. you can pull air/ash/co. from the stove and 2. it's just is the right way to install these..

 

[Lindsay]

I was speaking of OAK = outside air intake not choke. Could be a possibility with the stove running and not having a fresh air intake from outside it is drafting fresh air from your furnace air intake drawing all the air through your vents and back through the filter. Along with that its pulling all the fine dust in your heating system back through the filter. As well its probably pulling fines from every nook and cranny in your home since its creating a negative pressure and lots of drafts..

to the post above he uses his fan in his heating system to circulate air

AHHHH ...... the intake for the stove is flex tube with a grate that is no more than 2 feet long and is right now sucking air from the space between the back of the stove and the wall. The wall faces NW, so are you suggesting that a solution to try might be running that intake through the wall to the outdoors? Very doable and relatively simple to do. Wow .... you’re very knowledgeable .... thank you.

 

[Mt Bob]

Still could be your air exchanger,if it is on same side of house as exhaust.

 

[zrock]

Yes run the fresh air intake outside. With it being inside with the stove running it is burning the oxygen from inside the house. This is creating a negative pressure in the house forcing air to be sucked through any crack/opening it can find in your home. This could be the cause for extra dirt in your filter. Should be more efficient as its heating the cold air in your home instead of creating drafts and then trying to heat it.

Sent from my SM-G950W using Tapatalk

 

[kenora]

I've got a PP130 in my workshop and am very happy with it...this is what the OAK looks like when its drawing -31c air (yup cold this morning...the water line (insulated and buried a couple ft) to the lake (with a heat trace line in it froze for a few hours) :|

anyway if it gets cold you'll have to deal with the moisture off that pipe...I have a cake pan under it..it collects the water when the ice melts (in July) and it evaporates..

 

[Lindsay]

I don't have a pellet stove. Boiler.

But with all those fans running pulling air from where your stove is, and the filter issue description, I would be quite concerned you could be pulling CO2 from your pellet stove, into your house. Which could be deadly.

So i checked .... all the detectors are Kidde combination carbon monoxide and smoke .... whew!

 

[Lindsay]

Still could be your air exchanger,if it is on same side of house as exhaust.

The air exchanger is on the opposite side .... thanks for the suggestion

 

[Lindsay]

I've got a PP130 in my workshop and am very happy with it...this is what the OAK looks like when its drawing -31c air (yup cold this morning...the water line (insulated and buried a couple ft) to the lake (with a heat trace line in it froze for a few hours) :|

anyway if it gets cold you'll have to deal with the moisture off that pipe...I have a cake pan under it..it collects the water when the ice melts (in July) and it evaporates..

Hey Thanks for that .... -31C eh? I’m in the Ottawa area and it’s a balmy -10C. I’m going to do the OAK tomorrow ... soon as Home Hardware opens!

 

[Lindsay]

Yes run the fresh air intake outside. With it being inside with the stove running it is burning the oxygen from inside the house. This is creating a negative pressure in the house forcing air to be sucked through any crack/opening it can find in your home. This could be the cause for extra dirt in your filter. Should be more efficient as its heating the cold air in your home instead of creating drafts and then trying to heat it.

Sent from my SM-G950W using Tapatalk

Thank you VERY much for helping me .... I’m going to install the OAK tomorrow. I will post some results. Thank you Zrock and all the other contributors.

 

[Lindsay]

Ok ..... this has been interesting! Before installing the OAK, I thought to call my local WETT technician for his thoughts on the problem of the dirty furnace filters.

He came over did the pressure test and nope I do not have a pressure issue. He told me that it is almost impossible to have a pressure issue in a walkout basement. He then began an inspection of all the joints on the exhaust piping and the door of my pellet stove.

The inspection was carried out using flashlight pointed 45 degrees from the pipe during the ignition process. We were able to easily see leaks. We found two big areas - one on the door and one at the L-joint where the vertical pipe joins the horizontal pipe entering the actual stove.

We wrapped the pipes with the metallic vent tape, shut the stove down and re-inspected during inspection - no leaks. For the door .... he told me to remove the existing rope gasket and re-install a new rope gasket, but this time to not use the glue that comes in the packaging but to use hi-temp silicon caulking and to put the rope ends meeting in a corner and NOT in a straight area.

Anyway, I’ll replace the rope gasket and report back. We also discussed heat distribution and the use of an inline fan to pull more heat from the stove up into the cold air return. I learned a lot from the discussions with you all and with him but I get the feeling that there is much more to be discovered. Thank you all.