Englander 25 PDVC Outside Air, gaskets, and other little tinker troubles

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Tom Bentley

New Member
Oct 9, 2012
24
I have been having my PDVC25 cleaned by a furnace company for 4 years now because I am tool illiterate. However, I decided this year to get bold and get in there and see what made this thing work. Its really not all that mechanically complex, however, removable side panels especially on the room air blower side would be a wonderful addition, since i'm old and fat and crawling around upside down on the floor and reaching into the dark for a screw is not my forte'.

Now or a question or two. Everyone tells me "the outside air is really not important unless your house is totally sealed up like a vacuum." However, this past season and again now I get a smokey smell if I am burning on low. Magic window settings are by factor 6-4-1 which fed tooooooo fast and burned way hotter than i wanted and I run now at 4-6-1. I notice that my fire goes up and down (high active flame then dwindles to tiny flame awaiting pellets). I would love to have a plan old steady, active flame reaching about the top of the burn pot and just holding there. Is it possible? Also i get some smoke smell when the flame is tiny waiting for pellets.

Take note my outside air is not installed but my house is drafty and the stove sits on a cold concrete floor. The first year my restrictor plate in the bottom fell of and everyone said don't worry about it you don't need it. Yesterday I found a screw that fit and I put it back in and closed it as far as it would go and the stove did seem to run somewhat better with a steadier flame but still great variance in up and down.

My last main issue is gaskets! Obviously, the pro's cleaning for the last 3 years said they took removed and cleaned the blowers, etc., but did they really? They never mentioned gaskets or replacing them and as I understand it you can't remove the motor to the exhaust/combustion blower without replacing the gasket. So I wonder #1 did they actually remove and clean, #2 just run their shop VAC long enough to fool me, or #3 actually do it and replace gaskets that I am having a terrible time finding to purchase locally. My last hardware store question and answer I go the recommendation to use hi temp silicone and make the gasket for myself? Any thoughts on that approach?

Sorry I have been so long winded here but having read lots and lots of posts I think this is the place that I can finally get some straight HONEST answers and opinions. So anything you could share would be most appreciated.

Thanks so much for helping a Do-It-Yourself novice. P.S. I've got the hole saw that makes the hole for the outside air -- just trying to get up the nerve to apply it to mybeautiful 14 inch wide board wainscoating and hoping to come out of the house in the same spot if you recommend installing the outside air. Who knows the wall may look like swiss cheese when i'm done.

Thanks again.

Tom
 
Hey Tom, and welcome to the forum.
I'm sure all of the "irregulars" here will be chiming in with solutions to your needs.. I have the same stove as you and do all of the maint. on it myself, including the install. I buy gasket material loaclly by the sheet and just cut it out for each diefferent gasket, cost's less that $1.oo each that way,
I too am not as limber (or slight of midriff) as I was 20 years ago, so on the rare occasions that I might have to get behind the stove, (and for annual cleaning), I have a set of wheels, like a movers doll, that is slightly larger than the base of my stove and about the same height as the hearth it sits on. When needed I simply detach my OAK and stove exhaust coupling, lift the front of the stove (using a flat bar) and put a 1/2" steel rod under the base from left to right and simply rool it onto the dolly, wiht another rod or two on the dolly. Once on the dolly I can either work on it right there or roll it out onto the back porch if I think it's gonna get messy.
As far as cleaning the fans, once I have the stove outside I get my little mechanics stool, our a milk crate and just start taking things apart,(being careful to remember how they go back together, cell phone camera is indisspensable for this), remove all gasket material, take blowers out, take fans out of blowers, clean everything till it's shiny, lube fans, motors, and put it all back together with new gaskets.
It really isn't too bad, although I'm sure it may seem like a daunting task at first, but then when you fire it up, knowing that it is clean and ready to work, it does give you a warm fuzzy feeling,,,, inside and out.

Hope this helps.

John
 
Ok, try 4-5-1 that should even out the flame fluctuation a bit and you really need to OAK that stove, it is required to maintain the safety listing for that stove and to have the installation comply with code.

I hear you on having to be a contortionist to work on some stoves, not sure the stove designers have yet.
 
Thanks Murph and Smokey. I wondered about gasket material but wasn't sure about the heat issue -- is there special gasket material that you can buy that you cut out? I'll sure be asking home depot this week as it would be great not to be restrained with ordering time, etc. I did get the motor out on the room air and used a tooth brush to reach in and clean the squirrel cage. Try as I may I couldn't figure out how to get that darn cage out of the housing though and I'm sure i'll run into the same situation with the combustion blower -- and pointers? As I am sure you can see by now I'm not terribly mechanical and am hesitant to take any bolt or screw out that I'm not sure what's behind it. I did it to a weed eater once and springs and strings flew every direction -- i bought a new one.

Smokey -- so OAK is important. Is it just for code reasons or will it make my stove burn better and without that smokey smell. I did a test i read about in here by putting 3 sticks of incense in the stove when it was off and waiting for wisps of smoke to appear where air might be leaking and the only place any turned up was out of the end of the outside air pipe which is, of course, currently not connected to anything. So what do you think -- might it cure my smokey smell a bit if I hook it up. I've decided to call my brother to drill the hole in the wall -- 75/25 he might hit the right spot in the house which is more desirable than my 25/75 chance that i would end up with swiss cheese.

Thanks again both of you for your input.

Tom
 
What you want is "lytherm" for the gaskets, I get it at a local HVAC/plumbing house, costs me about $7 for enough material to make about 15 gaskets. If not available locally, I believe other members have bought it off eBay, Amazon, or directly over the 'net, just search "sheet lytherm".
The squirel cage motor has a set screw at it's base that hold it onto the motor shaft, you need a longer allen wrench the goes into it from the side through an opening in the fins of the cage that the maufacturer put there for that purpose. Take it off, and clean it real good, making sure not to bend any of the fins. Blow it off with compressed air, and I usually spray it with graphite so the dirt and stuff has a harder time sticking to it before I put it back on.
the other fan is a little different, it is made of flat, bent fins, again there is a set screw (if I remember right) that holds it onto the shaft, again clean it, blow it off, use graphite if you want, and reassemble. Make sure you clean, vacuum, the air paths in the housings around the fan blades, they get pretty gunky sometimes.

John
 
I just completed my yearly cleaning. I consider myself very competent mechanically, so would not recommend you remove the fan from either of the motor shafts. It's not necessary, as both can be cleaned easily blade still installed. I like to blow them out with compressed air, holding the fan with my finger so it won't spin, and use a small brush to get 95% of the dust off. The motor gasket for the exhaust fan is always a throw-away, disintegrates at the mounting screw locations when disturbed, and you can't do a proper cleaning with the motor bolted to the housing, IMO. I order a 2 year supply of exhaust blower and burn-pot gaskets in the off season, not too expensive. The room air blower can be removed and reinstalled no new gasket req'd.
 
I buy gasket material loaclly by the sheet and just cut it out for each diefferent gasket, cost's less that $1.oo each that way,

I would like to know where you get gasket material by the sheet. Buying it pre-cut is expensive and usually inconvenient.

I also want to put my two cents in:
I just rebuilt a PDVC-25 and I thought that you might benefit from what I observed.
  1. The outside air kit is essential. Wind against the side of your house can cause positive pressure on the vent. The combustion blower has to fight that pressure to keep air moving through the stove. That causes the burn to vary depending on the wind. With the combustion air coming from the outside the wind pressure is on both and cancels out.
  2. When cleaning the combustion blower on the PDVC-25 it is only necessary to undo the outer set of screws. That is the set of screws that hold the motor mount to the blower housing. That gasket is reusable.
  3. If it becomes necessary to remove the blower housing from the stove that gasket should be replaced.
  4. If the convection blower gasket is in good condition (no tears) it can be reused.
  5. The door gasket and hopper gasket take a lot of abuse and should be inspected for signs that they have gaps or leaks.
  6. When re-installing screws into sheet metal, gently turn the screw backwards (as if removing) until you hear or feel it click and then start driving it forward. This allows the screw to find the threads that are already cut in the edge of the sheet metal and avoids stripping the hole.
  7. Try not to bend the fan blades of the combustion blower. They are thin and easily bent. Bent blades will make the blower vibrate making noise and shortening the life of the bearings.
  8. When removing any assembly from the stove make sketches or take pictures of how it was, including where the wires went and the sequence of any stacked parts. That way, if you get called away and have to come back at it cold, you will have a reminder.
Don't be intimidated, it isn't that complicated.
Harvey
 
Snip ...
Smokey -- so OAK is important. Is it just for code reasons or will it make my stove burn better and without that smokey smell. I did a test i read about in here by putting 3 sticks of incense in the stove when it was off and waiting for wisps of smoke to appear where air might be leaking and the only place any turned up was out of the end of the outside air pipe which is, of course, currently not connected to anything. So what do you think -- might it cure my smokey smell a bit if I hook it up. I've decided to call my brother to drill the hole in the wall -- 75/25 he might hit the right spot in the house which is more desirable than my 25/75 chance that i would end up with swiss cheese.

Thanks again both of you for your input.

Tom

Tom that OAK is required by the manufacturer of the stove and must be installed or your safety listing is no longer valid and any representation to your insurance company about having installed it to the manufactures instructions and that the stove is safety listed is incorrect, It is also a code violation in most jurisdictions.

It does also help with providing a better natural air flow through the stove which in addition to helping keep smoke out during a power failure also can help with a smoke smell at start up.

What really helps with startup smoke smells is a fast ignition especially when a stove has an air wash.

You need to be certain your ignition is fast and that you locate the source of your smoke during an actual start up.

I would expect incense to exit the intake under no draft situation especially if there is a slight negative pressure in the room the stove is in. Yet another thing an OAK takes out of the picture.
 
WOW Great info guys -- I really appreciate it. I'm getting braver by the minute and you all have definitely convinced me to take the saw to the wall and hook up the OAK. Here goes!!!!!!
 
Tom,
Don't know where your located, but I got a whole shop fulla tools if you need em!!!

John
 
Regarding the fluctuating flame, I find it to be it`s somewhat normal in this stove and not a whole lot can be done since it`s all about how the feed system operates. The top auger feeds pellets only intermittently onto the continuously turning bottom auger and an inconsistent amount gets pushed into the burn pot every revolution.
That said it shouldn`t be a problem unless there is unusually long intervals between the high and low flame fluctuations.
 
Yikes - I'm really confused here. I just attempted to clean the exhaust blower. First I took the three nuts off the little brackets that hold the motor on - it won't come out and I'm not about to pull any harder. Next I removed the six nuts that look like you should be able to them remove the mount without removing the entire blower -- it didn't seem to want to come off either - should I just pull harder or pry it off -- totally unclear what to do here.

Thanks

Tom
Nevermind -- see below.
 
Okay -- I got the dang thing off. There really wasn't much dirt in there -- a little disappointed! All that work and nothing major to suck out of it. Now the gasket is the problem. It looks to me like the pro's have been using that liquid kind of gasket -- its kind of a rusty/red color and there isn't much left of it. I have a tube of high temp gasket maker but its called RV Blue I think. It rated up to 450 deg's and the lumber/hardware seems to think it would be fine, Usually used for automitive i think. But thinking maybe first i'll just screw it all back together and if there's no smoke smell, etc. let her run. Any thoughts?

Thanks tom.
 
Tom there is supposed to be a fiber gasket between the motor mount plate and the blower housing making the motor and impeller easy to remove that is why there are six nuts, there should not be any type of rtv there.
 
Well, as it turns out, i decided to do nothing but clean it really well and put it back on. I will obtain a gasket and repeat the procedure next week. I started it up just to make sure everything was running and it worked fine. A little smoke smell which dissipated after it got going. I plan to pick up an extension for my drill and cut that 2-1/2 inch hole in the wall and place the OAK in operation next day off (this coming monday or before if I get half an hour to myself and see if that doesn't cure the smoke smell entirely. I think i have good exhaust -- certainly the flame blows well when after manually light it I close the door and the flame is definitely powered by the blower. I ask is fine and dark grey and permeated with the same pattern as the wear plate holes with no clinkers. So looks like I am getting there. OAK and install a gasket are the last things to accomplish this week and a little wire brushing of the auger tip to clean it up.

This has been a learning experience and I'm sure next cleaning will go much smoother. Starting understand how this devil works. Hate the thought of ordering those expensive gaskets and am looking this week for the Lytherm to make my own - after seeing the motor gasket its a very simple pattern to reproduce indeed. Its not the price of the gasket that bothers me - $13.00 for the gaskets but the additional $13.00 for Shipping and Handling really sticks in my craw. Call me cheap if u want.

Many thanks to ALL of you for your input. Your advice and experiences have been invaluable and I look forward to bugging you further in the near future. I will be following this forum religiously.

As always any further info/help/advice/thoughts/jokes, etc. are always welcome!!!!

Tom B
 
PS from Tom==

I was surprised and pleased to see there was no squirrel cage inside the exhaust blower. Hope there wasn't supposed to be!!!!!!!!

Tom
 
Hate to bug you all again but here's another question. I am getting a very smokey smell when burning on low (1) with 3 bottoms set a 4-6-1. Tried upping to 4-8-1 still same problem. I get let if I increase to 5-8-1 however, it is toooooo warm in here and i'm a pellet mizer as well.

Getting ready to change the exhaust blower motor gasket this week in case that's part of the problem. but where i seem to smell the smoke the most is on the dura vent 45 going out thru the wall. I have heard that all seams should be "sealed" -- with what? I really like to take them apart for cleaning, etc. so hate to seal them up forever. I have some really cool Aluminum tape -- perhaps that? I did seal out side the thimble on the exterior wall but not the interior.

When I took off the exhaust blower motor the seal had pretty much disappeared so I am limping along without one however, i don't smell smoke down there. The pros have been cleaning it for the last 3 years and I'm not sure they ever put a gasket in there. The remnants of gasket were kinda reddish and stretchy - is that correct? I am planning on going to automotive store tomorrow in search of Lytherm material to make my own. If I can't find Lytherm -- will other high temp automotive gasket material suffice?

Thanks.....

Tom

P.S. really curious about sealing those seams in the duravent the easiest way possible as well as making it convenient to clean. Please some thoughts?
 
Jeez.... still working on the smoke smell issue. Have ordered from Englander the appropriate motor gasket even though i can't sense any leak there. The smell is only on low burn and I have played with the bottom three magic buttons every way possible. Original 6-4-1 goes thru pellets too fast and makes much more heat than I want right now even on setting 1. Latest try was 3-7-1 and while it created about the amount of fire I wanted and perfect for temp, i get the smokey smell pretty bad. So....... I tried the "incense" test again but this time sealed up the outside air to make sure the incense smoke went out the exhaust to check for leaks. Well - I got incense smoke for sure but from a most unlikely place. nothing around the exhaust lower or even up the pipes, nothing around the door or window, but at the bottom of the stove on both sides where the front angles back (i guess its about 45 degree to make the corner around to the side of the stove if I'm making any sense) smoke was jetting out and down .... u can stick your finger up in there a bit i am assuming the stove housing bolts together there somehow.

So I'm sort of wondering .... how does it get from inside the stove to somehow between the stove and the stove outer shell? Could a bad burn pot gasket be the culprit? I have the feeling the professional cleaners probably never replaced that one either (I'm really starting to feel badly about paying $189 a year to a professional furnace company for a half-completed job) especially since the main reason I had it done professionally was to make sure all was SAFE -- fire freaks me out and I worry about leaving the house with things burning inside).

So what do you think guys -- order another gasket for the burn pot and pull it and replace it too? OAK is still waiting to be installed this week -- we've been having steady rain for the past two days so haven't gone outside to cut that hole yet. I am so hopefull that OAK is going to make my life easier and help with both the smell and burn issues.

Tom
 
You could have a broken seal around the adapter, the clean out tee cap is leaking, or one of the vent seals was broken.

Why in the world would you think a furnace service company would know how to do an annual maintenance job on a pellet stove? We have seen cases on here people have hired professional chimney sweeps to do the job, fine clean vent and a pile of ash in the combustion blower with a stove that won't light.

ETA: Get that OAK installed.
 
Smokey this may be a double post -- The companies I called assured me they do this all the time -- but i am now doubting that -- Pretty sure my tee out of the stove is good - check carefully with a light and inside the cap is sealed well with RTV. When you say possible "vent seal" broken - do you mean on the vent pipe outside the stove? My set up is as follows -- Tee out of the back of stove, 43 inches straight up, 90 elbow at top to pipe going thru the thimble and out 2 feet from exterior house. I question the 90 at the top since I smell smoke more strongly when running my nose up and down the pipe in operation. The only "iffy" install part is tee connected directly to stove -- there is not enough room to put an "adapter" in there but the fit seems to be snug and tech support says not ideal but workable and safe. The suggested perhaps rtv'ing that in but I'm pretty sure that its a good fit. Not meaning to be a pain here -- just trying to learn.

Tom
 
Get the rtv on the vent to stove section, be certain to also fill the area between the inner pipe and the outer pipe, and some metal tape on the joints in that 90.

Hopefully there is sealant in the area around the vent where it exits the thimble on the outside of your house.
 
Thanks Smokey -- Yes I have sealed around the thimble both on the inside and outside. I will now apply the 3M metal high temp tape I bought yesterday on the joints in that 90 and fill that part that joins to the stove with rtv. My metal tape is rated at 350 degrees which I have been told is sufficient. OAK will go in by this weekend at the latest -- on first attempt to install I found out you needed a "pilot" for the hole saw that goes on the drill --- wish they'd tell you these things when you buy something rather than waiting til u get home to read the package insert and instructions for use to find out you need another part (kinda like batteries, etc. hahahaha). Thanks for all of your help -- I think by next cleaning I will have all the tools and skills necessary to really do this up right!!!!!!!!!

Tom
 
Here is my two cents worth.
  • It is highly unlikely that smoke is coming out of the burn pot gasket since that area is under negative pressure. The only way I can see that happening is if the combustion blower is not running continuously and that should never happen.
  • It is unlikely that smoke can leak from the combustion blower motor gasket. That area should be at a slight negative pressure caused by the impeller pushing air tangentially out.
  • The blower housing gasket is at positive pressure and a leak there could blow smoke down towards the bottom of the stove.
  • There is suppose to be an adapter that marries the stove exhaust pipe to the vent pipe. it has a seal between its wall to prevent smoke from traveling between the walls.
  • I have seen smoke weeping out of joints on Duravent tees and ells during startup. Turn off the ambient lighting and use a highly directional flashlight to visualize the smoke flow.
 
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