Profile 20 extremely sensitive to outside winds...

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MrBeetleman

New Member
Dec 20, 2010
28
Canada
I have been having troubles with my stove smoking VERY badly on startup, and poor burning in general.
I knew the first thing was to clean it (which I did.) Better, but still not right.
I tested the combustion blower motor for voltage: 78v at startup, and 115 after a few minutes.
The motor sounds like it is working fine, but I think it might be getting lazy. If there is any back pressure, the flame wavers, etc, and will be blown out.
The fact that outside air gets into the combustion chamber so easily kind of rules out internal blockages right?
 
MrBeetleman said:
...The motor sounds like it is working fine, but I think it might be getting lazy. If there is any back pressure, the flame wavers, etc, and will be blown out.
The fact that outside air gets into the combustion chamber so easily kind of rules out internal blockages right?

That's not conclusive evidence that it is getting to the firebox or of lack of internal blockages, what you are seeing is likely the effects of the pressure difference the vacuum switch is seeing, that will cause the auger to pause and then restart that results in the flame wavering, if it continues long enough at one time the stove will fault.


If it was making it all the way into the firebox I'd expect to see some smoke coming out of your air intake.
 
I am starting to lose my mind! The whole winter has been nothing but smoke at startup (not the same amount each time, but still there), and eventual burn outs! I have taken it completely apart and cleaned it. Replaced door gaskets, leaf blowered it, etc...
When the combustion fan was out, I shoved a shopvac in with a gasket of rags. While it was running, the air was howling out the upper 2 exhaust ducts beside the air exchange tubes freely.
The only place that isn't directly in view is behind that rear false wall (extending from the upper 2 intake holes, down to the damper), and I have shoved brushes in there from both ends, and banged on it with hammers, etc.
I have completely brushed out the exhaust pipe....
 
Does that stove have a photo-eye as its proof of fire system?

Those things are noted for getting dirty and then the stove doesn't think it has a fire anymore.

You have likely already told us about your vent system if you haven't would you please do so starting at the the stove, when did you last clean that in particular the termination cap?

I'm going to look over your prior posts.
 
Hello

Can you post pics of your stove and the flue venting so we can help you better please?

Thanks
 
I'll try to post these...
I'd like to try to post a vid of my troubles eventually...
042.jpg

043.jpg

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Is that 3" or 4" pipe?

If it is 3" pipe your EVL is likely over limit.

How long is that vertical section and the horizontal as well?
 
MrBeetleman said:
6' vert
3.5' hor

It worked fine for the previous 2 winters though...

Yes but it could be dirty, you have a horizontal portion that loves to collect fly ash, and then the tee and 45 degree elbow together is another fine ash trap.

If the piping is 3", your EVL is 19 which is over the normal EVL of 15 for 3" pipe.

If the piping is 4", your EVL of 19 is well within the normal limit for 4" pipe.

When did you last clean the vent and in particular the termination cap's screen?
 
Hello

Here is a good definition of EVL for people reading this and since I forgot!! LOL. Are you above 3,000 feet sea level??
So what is your EVL? Given that twist in back also adds approx 3 EVL right??

Also see here for more info >> http://nevelsstoves.com/pellet-stove-venting.html

Pellet stoves have to push the exhaust air through the vent pipe with the stove's exhaust fan. With less restriction your pellet stove will breathe easier and burn more efficiently. First let's clarify the word restriction. Restrictions come from several different items.

1. 45 degree elbows
2. 90 degree elbows
3. Horizontal distance
4. Vertical distance
5. Elevation where you live.

A rule of thumb equation we are using has been adopted by most pellet manufactures. The equation is called the sum of Equivalent Vertical Length (EVL). All of the above mentioned venting restrictions have been assigned EVL values as follows:

1. Each 45 degree elbow = 3 EVL
2. Each 90 degree elbow and Tees with cleanout = 5 EVL
3. Each foot of horizontal run = 1 EVL
4. Each foot of Vertical run = 0.5 EVL
5. Elevations above 3000 ft with an EVL of 7 must adapt to 4 inch vent pipe.

If your installation is below 3000ft, we would need to do some math. The rule of thumb equations is that if the sum of the EVL is 15 or greater, then the pellet vent pipe would be increased to 4 inch diameter pellet vent pipe.
 
Since it has already worked perfectly for 2 winters, the problem isn't with the vent pipes.
Let me quote from my previous post, "I think the problem is the heavy cold winter air in your vent pipe. The air from the combustion blower encounters a lot of air resistance when it first starts-up since the air is cold and heavy, not hot and light. The smoke in the stove doesn’t move out the vent right away because the air in the vent isn’t moving much so it leaks into the room. Do what I do and let the combustion blower run for half a minute before lighting the stove." This should work if your stove allows control of when the igniter is turned-on. Another possibility is that the combustion blower isn't starting up and blowing at it's normal speed until after a short time has passed. That results in a lazy flame and poor combustion, i.e. smoke. Mine has done that many times. Last night after learning a few new things from reading posts, I checked the wire connections to the blower and found one wasn't pushed-on fully, it was kind of loose. That may have been the problem. Or lack of oil to the ancient blower, which I took care of.
 
Thanks everyone for the replies.
I have swept the entire pipe clean.
My stove lights automaticly, so I don't think I can adjust when the blower turns on, but I think it is running for a while prior to lighting.
There is only 78v going to the motor at startup, but then within minutes it goes up to 115v. I thought that was so the 'new' flame had a chance to establish itself, prior to going 'full strength'.
I'll check for loose connections...
I have an 'oilless' motor, but have cleaned it well, and tried to oil the rear most bearing.
 
MrBeetleman:
It's good to see another Canadian on the board -- although I'm a New Yorker now. :)

I have a Profile 30 insert version of your stove stuck in my fireplace. I have a straight verticle 23 foot 3" flexible stainless vent pipe running from the lower floor of our our house to the top of the fireplace chimney. I do not have an OAK.

After a few years of operation, I started getting a 'burst' of smoke at the moment of ignition. The 'burst would blow into the room by flowing backwards through the window glass air wash system (holes) for a second or two. When the fire started there was also a 'cool looking' burst of flame in the stove. I also had the damper nearly wide open - but would still get a bit of a lazy flame along with some soot and black smoke. On a windy night I could see the fire in the stove 'dance' in tune with the howling winds out side.

After cleaning the whole stove very well and only seeing marginal improvement, I decided I should check the exhaust vent. I pulled the clean out 'T' off of the back of my stove and tapped the pipe quite hard with a screw driver handle. Big mistake -- as several pound of really find ash avalanched down the pipe around the 'T-corner' and on to the floor of the fire place. And, of course, a big burst of this very fine ash also blew into the family room creating a huge cloud! What a mess! The Mrs. was not pleased. :)

I then got a several big green garbage bads and tied them over the exhaust vent. I shook the pipe several times and banged it against the side walls of the chiminey (it dangles in my chimney). I think I dumped another 10+ pounds of very find ash out of that exhaust pipe! I vacuumed up my mess - and vacuumed all surfaces in the entire family room - took my deserved verbal abuse from the Mrs. and reassembled the stove. All worked like new thereafter.

I have since bought the chimney sweep rods and a brush on Ebay. I now clean my exhast pipe every fall. I place a shop vac hose at the bottom in the 3" pipe and seal it to the 3" stainless pipe by wrapping it with a garbage bag and duct tape. I still clean several pounds of ash out of that pipe every season. But my stove works great -- no more smoke bursts into the house at ignition and I run my damper only 1/2 way open.

Food for thought?

RonB
 
Mr. Beetleman:

I forgot one more thing. My Profile 30 insert has two small black metal doors about 5" x 5" on the back wall of the fire chamber below the phoney-looking fire bricks (left and right side of the fire pot). These are level with the ash pans. These doors are held in place with one screw each. When these doors are removed, they reveal two passages in the back where the smoke and hot air travels down from around the heat tubes on the way to the combustion fan. I didn't know these doors were there in the first years - as they were not documented in the manual that shipped with the stove.

I open an clean the stuff behind these doors once each year. There is ussually lots of ash back there.

If you haven't cleaned these I think it worth the effort.

Take care.

RonB
 
Wow, I wouldn't have guessed that there would be so much ash in the vent pipe. That's very important information. I guess the ash slowed the combustion air so much at start-up that the combustion chamber couldn't fan the beginning flame well enough, nor move the resulting smoke out the vent fast enough. But once there was enough heat being produced, the heated air helped the blower by increasing the strength of the draft up the vent. Since the blower is only getting 78V at start-up, the ash build-up has an effect that it might not if the blower was receiving full-power right away.
 
arnash said:
Wow, I wouldn't have guessed that there would be so much ash in the vent pipe. That's very important information. I guess the ash slowed the combustion air so much at start-up that the combustion chamber couldn't fan the beginning flame well enough, nor move the resulting smoke out the vent fast enough. But once there was enough heat being produced, the heated air helped the blower by increasing the strength of the draft up the vent. Since the blower is only getting 78V at start-up, the ash build-up has an effect that it might not if the blower was receiving full-power right away.

The other effect that this sometimes causes and that you don't want to see is called delayed ignition. That can force the door away from the stove frame and if you have a cracked window glass cause that to open up and _________ (insert all kinds of bad things happening here) .
 
I have cleaned the whole exhaust pipe.
There aren't the 2 doors on the back wall of my profile 20, so it is really hard to clean that section. The only part of the whole stove I don't have direct visual access is the short passage down behind the false rear wall. Everywhere else is visually spotless, and I have done my best to get that section the same.
 
According to the owners manual the two ash clean-out ports are placed behind the fire brick panels on a Profile 20.

On a Profile 30 they are placed below the fire brick panels and can be accessed without removing these panels.

On a Profile 20 the fire brick panels must be removed first. See illustration below.

On my Quest Plus there are no ash clean out ports at all... so a looong bottle brush is needed for cleaning. Also, banging with a hammer on the "exhaust manifold" helps driving out the crud.
 

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Thanks for the diagram, but mine does NOT have the clean outs.. Mine must be an older model. Thewy must've modified the design later, to improve cleaning....
 
Do you have a leaf blower that also acts as a leaf vacuum?

If so and you have a way of safely getting to the venting outside you can use that to suck out even crud in the ash traps provided you first loosen up that crud.

Take the fake brick out and thump on the back wall of the firebox, I'd use a block of wood placed against the firebox wall and thump the wood with a hammer, just keep the hammer away from the door glass.

You may also be able to get any mess in the traps out by using a high powered shop vacuum from the inside after removing the vertical pipe from the 45 degree elbow along with the thumping.

I'd spend a little bit of time looking for perhaps small round plugs in the area the ash traps are in the picture Stovenson provided. If you find something like that a small hose can be attached to a vacuum and shoved in there to get at any ash.

ETA: You might also send a PM to Wood Heat Stoves with your email address, stove make, model, and serial number and inquire about a service manual for that stove. I'm sure that Dave Gault would be happy to send you one.
 
Dave has sent me the manuals. There aren't any access plugs to these ash traps. I have done the leaf blower trick as well!
Thanks for all of these suggestions. I am sure I'll get this figured out just before spring gets here....
 
MrBeetleman said:
Dave has sent me the manuals. There aren't any access plugs to these ash traps. I have done the leaf blower trick as well!
Thanks for all of these suggestions. I am sure I'll get this figured out just before spring gets here....

Glad you took Dave up on the manual.

Did you do the thumping before using the leaf blower?

The first time I used the leaf blower it did fine on the venting but not in my ash traps as stuff was really stuck. At least I could remove the baffles and have direct access so was able to scrape the crud out. Since then I only inspect the traps after using the leaf blower every third use.

Because of the angles and length of the run you might have to take the venting off of the stove.
 
I trust you have checked your gaskets, door gasket, ash pan, and hopper (whatever is on your stove).

As for the cold air in the vent pipe one should note that while possible is a bit unlikely with an inside run.

However a slight bit of restriction in a 3" vent of that length can cause a problem for the combustion blower to overcome.
 
I restarted the stove this morning and tried to get a video of it...
If I disconnect the ignitor, and manually light it, it is better, but still not right...

 
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