Installing used pellet stove and chimney

[JTBurner]

Hello,

Buying a used Harmon p38 stove with chimney 4" size...I have a current Whitfield stove which is 3" chimney.. I will be using the 4" chimney for the newer stove.. my question is when I install the 4" piping, should I use a fire retardant coating on the surrounding wood where the thimble goes through the wall.

(broken link removed) Example...

I have an old 135 year old home, so this is something that I want to make sure of before I install and button up to finish... old wood with high temps - cautious...

Do or does anyone do this? Maybe put sheet metal covering over the wood?

Not sure as I did not install the original pellet stove flue in my house..

Thanks for the help..

 

[corkman]

Post some pics of the current install. You should have a thimble that the pipe passes thru from inside to outside

 

[bogieb]

It is interesting that the P38 has a 4" pipe as most are 3". Unless you have a long run or a lot of 45* and or 90* elbows, you shouldn't need the 4". That being said, I don't think it would hurt to use 4", you just may be going thru extra work that isn't needed.

I believe that part of the purpose of the thimble, along with the double-wall pipe, is to enforce the minimum clearance to combustibles (I could be full of sh*t and I'm sure someone will be more than happy to correct me on that if needed ). But for peace of mind, and to stay on the safe side, I don't see anything wrong with covering with fire retardant or sheet metal. After all, I put up a heat shield on a wall that is to the side of my P43 even though it is outside the clearance area after I put heat shields on the stove. I didn't like how warm the wall got, so erred on the side of caution.

 

[JTBurner]

Actually - the piping may not be 4" I am just looking from a pic from the add...My 3" is selkirk - the piping in the pic attaches to a 3" on the stove, but seems to be a lot bigger on the T itself not that it means anything but it is black in colour seems much bigger than the connection in the stove .. being that the flue locations on the 2 stoves are different, approximately 7" in vertical height difference, I have to make some adjustments - Question I am assuming that if there is a vertical drop that connects directly to the stove that a T with a clean out is required..

Once I see the stove in place etc, I can make a better judgement to keep the Selkirk or use the newer pellet poping...

Thanks for help...

 

[bogieb]

Here is a manual you can download. It will give you a lot of info on exhaust configurations. Your country / providence may have specific requirements also so you should check that out too. A cleanout is beneficiary but may, or may not , be required.

Please help us help you by posting pics of your current exhaust set up for the Whitfield; at this point we are just guessing and trying to account for many variables that may or may not exist. There is a huge difference between a 3 ft vertical to termination with two 45's and a 15 ft vertical to termination with two 90's, or even a short vertical with many elbows (such as mine - which you can't see in the pic above and most people would assume is a straight out exhaust).

 

[JTBurner]

Here are few pics of the existing piping... the exhaust goes straight out on the whitfield, then tee's and rises approximately 19'..

Thanks for help...

 

[Lake Girl]

Need to figure out diameter on piping. 19' vertical = 8, 90* = 5, 45* = 3, 3' horizontal = 3. Shooting for EVL of 15 to 20 depending on stove. Higher EVL benefits from 4" venting.

Before you bring the Harman in, you should give it a good cleaning outside using compressed air to clean out internal exhaust and blowers. Disconnect vac switch when using compressed air.

 

[bogieb]

What concerns me is if that is 3" pipe on the inside, and 4" on the outside, then it almost looks as if the adapter and connection to the adapter is inside the wall itself. Connections should not be inside the wall. Maybe the transition takes place at the T outside and it may be okay?

If that is 4" pipe outside, with all that rise, that is a good thing. Lake Girl has some good info on the EVL (and initial cleaning of the stove).

If you replace the thimble, may I suggest you get one that can accommodate an OAK too? Being an old home, I would guess there are a lot of natural drafts within the home, and those most likely will become more troublesome if you don't use an OAK. An OAK is not required, but I believe it will be helpful in perceived warmth.
And regardless of what you do, I would assume you plan on replacing that elbow inside. It looks like it has seen better days.

 

[JTBurner]

With the purchase, I will be getting the newer piping \ thimble etc, so I can use the new piping if needed..

The existing 3" inside my house connects outside, I can see where the connections are.. the existing 3" looks odd, the original installer put that brown \ reddish colour stuff on it maybe RTV, I am assuming to prevent leaking.. saying this, I have used the existing for 15 years, never had as issue with it either.. there was foil tape on it, so I when I removed it a few days ago, that seems to be the colour..

With the newer stove, the owner just had the stove cleaned professionally.. However, I am so use to the old Whitfield, it might be a good thing to take a peek to see where and what I need to do... any additional advice or videos for installing Pellet piping? It really does not look hard, but good advice is always welcome.. what is the best sealants to use etc?

Thanks,

 

[Bioburner]

Except for the stove to pipe adapter that I will use a high temp silicone (permatex red rtv) the rest of the joints get a couple wraps of self bonding silicone tape that's easier to remove and since it stretches it usually stops most leaks. Looks better too. The tape can be found in both electrical and plumbing depts

 

[JTBurner]

HI,

Just getting back to this... So I have the stove hooked up, used some RTV silicone on the joints, cleaned the stove good, started up, that takes a little getting use to, but eventually got it going.. The stove works well, it can throw some heat that is for sure.. Funny thing, I bought a new Carbon M + Smoke detector and pretty much sat over the stove for 15 minutes with it in my hand to see if it could detect anything... LOL - my wife thinks that I need to be committed.. Not far off thou... One thing that was strange though.. I turned the stove down a bit, either the pellet feed and or maybe the temp - I forget.. after a few minutes, the distribution motor went off for close to 15 seconds.. it then came back on, not sure if this is normal?

I have the 2 pot controller board.. If that makes sense with a 2 pot CB?

Thanks for help...

 

[Bioburner]

I don't know about the 2 pot switch stoves, but the rest will shutdown the blower if room temp is met and the auto-manual ignition switch is on manual. Stove can be made into what is called fireplace mode, fire without heat distribution.