Quest plus hopper fire

[Neilt]

RTHL221B1008 Honeywell.

I agree with stoveguy that all of the signs point to his theory.

I put two handfuls of new pellets in the stove and turned the auger on, just to push the burnt stuff out. I did not light it. The auger seemed to work fine, I'm just wondering what all I need to replace gasket wise etc. thanks guys. You guys are awesome.

 

[SmokeyTheBear]

shouldnt have done it due to the stat if it was designed to operate using one. unless it balked starting but if that were the case it shouldnt have fed enough fuel to build up in the chute. im still thinking starve smother

The stove is not in an on/off mode because it is manual light so we can rule out the t-stat refiring the stove and doing a start up fuel load. The controller will only do ramp down and ramp up providing the low limit is happy, it should also do a shutdown if low limit is no longer seen with restart blocked and a fault light shown.

 

[stoveguy2esw]

The stove is not in an on/off mode because it is manual light so we can rule out the t-stat refiring the stove and doing a start up fuel load. The controller will only do ramp down and ramp up providing the low limit is happy, it should also do a shutdown if low limit is no longer seen with restart blocked and a fault light shown.

okies, didnt know if it was a manual light type with a hi-lo or a autolight with on-off. im not really familiar with that model stove , i do know the tendancies of top feeders though which is what im basing my theory on

 

[iceguy4]

For me ...I would have to know exactly what happened before I would EVER trust that stove again. Having a pro look at it may be the answer...BUT if he couldn't show me exactly what happened....a new stove would be in my future. Correct me if I'm wrong...aren't hopper fires rare?

 

[SmokeyTheBear]

okies, didnt know if it was a manual light type with a hi-lo or a autolight with on-off. im not really familiar with that model stove , i do know the tendancies of top feeders though which is what im basing my theory on

Top feeders and I are good buddies and running on hi/low is how mine is set up.

 

[SmokeyTheBear]

For me ...I would have to know exactly what happened before I would EVER trust that stove again. Having a pro look at it may be the answer...BUT if he couldn't show me exactly what happened....a new stove would be in my future. Correct me if I'm wrong...aren't hopper fires rare?

Not if things aren't kept up to snuff and both top and bottom feeders can have them.

Which is why several of us here harp on cleaning.

 

[Neilt]

Smokey, that cleaning process is for the quest. I have the quest plus, there is nothing behind the fire brick to open. I have read that if you call Lennox, they will instruct you to drill holes to clean, and where to drill. That didn't sound right to me though.

Here is a link to how I cleaned my stove before burning the ten bags.

https://www.hearth.com/talk/threads/quest-plus-burn-problem.116427/#post-1567290

My stove was then like the last post where it was getting to much air, and the damper never seemed to make a difference.

 

[iceguy4]

Not if things aren't kept up to snuff and both top and bottom feeders can have them.

Please set my mind at ease...If I run my stove on manual , my chances are slim of suffering the same fate...Between my 2 airtight hoppers I have over 1000lbs of fuel!

 

[SmokeyTheBear]

Smokey, that cleaning process is for the quest. I have the quest plus, there is nothing behind the fire brick to open. I have read that if you call Lennox, they will instruct you to drill holes to clean, and where to drill. That didn't sound right to me though.

Here is a link to how I cleaned my stove before burning the ten bags.

https://www.hearth.com/talk/threads/quest-plus-burn-problem.116427/#post-1567290

My stove was then like the last post where it was getting to much air, and the damper never seemed to make a difference.

If there are no clean-outs on your stove you have to use an air compressor and go in from above and you also have to run a snake with a small brush end down from above or in from the combustion blower cavity before using the compressor or call Lennox and get the clean-out enhancement.

 

[Neilt]

Will do smokey. Thanks again. Ill post whatever I find, but it may be a few days until I get to work on it.

 

[Neilt]

One last odd thing, there was a dark liquid on the ground at the foot of the stove. Maybe six ounces at most. This also pulled the paint off the footpad it sits on. The liquid felt like water and didnt smell, but was almost black. That has me stumped

 

[stoveguy2esw]

One last odd thing, there was a dark liquid on the ground at the foot of the stove. Maybe six ounces at most. This also pulled the paint off the footpad it sits on. The liquid felt like water and didnt smell, but was almost black. That has me stumped

this is residue from the smoulder (similar to creosote)

 

[SmokeyTheBear]

this is residue from the smoulder (similar to creosote)

And the reason why I said that the clean out is really an outside job as all of the surfaces that came in contact to the smoldering pellets or the smoke from it will need to be cleaned usually warm soapy water and this makes a mell of a hess not to mention some of the residue is creosote.

 

[SmokeyTheBear]

Please set my mind at ease...If I run my stove on manual , my chances are slim of suffering the same fate...Between my 2 airtight hoppers I have over 1000lbs of fuel!

The fact that hopper fires happen is why those hoppers are air tight as a fuel needs oxygen to burn, no oxygen it dies. This is also why if you have a hopper smoldering and generating smoke you never open the hopper lid.

Gaskets exist to help contain things to the proper side of the device and must be kept in shape.

There are no guarantees in life that you don't provide for yourself, everything breaks.

To put things in perspective that liquid fuel used in some devices has been known to leak and the end result also isn't pretty.

 

[stoveguy2esw]

Please set my mind at ease...If I run my stove on manual , my chances are slim of suffering the same fate...Between my 2 airtight hoppers I have over 1000lbs of fuel!

biggest thing to remember is that while any pellet stove can burn back, a well maintained one is far and away less likley to do so. the OP's unit may hae been well maintained, sounds like he was diligent enough in cleaning the stove out prior to use, but the gasket condition of the unit could be an issue (one we havent yet discussed)

 

[SmokeyTheBear]

We also haven't discussed possible safety bypasses. One of the reasons you really have to check over any stove you decide to fire up before hitting the switch and/or striking a match.

 

[stoveguy2esw]

We also haven't discussed possible safety bypasses. One of the reasons you really have to check over any stove you decide to fire up before hitting the switch and/or striking a match.

true dat, though i do not know the inner workings of that make of stove so i would be of less help in that respect

 

[Neilt]

As far as safety switches being bypassed, I am not that familiar with how many are on the stove, but I can tell you that I replaced the low limit switch, and the high limit switch does not look to have been tampered with... As it is an older stove these were the only two safeties I noticed(I am not saying that is all it has).

 

[iceguy4]

We also haven't discussed possible safety bypasses. One of the reasons you really have to check over any stove you decide to fire up before hitting the switch and/or striking a match.

Smokey,
You made me think...buying one of these pellet burners with no previous knowledge of the actual unit is very risky. In my mind I had kinda put them in the same category as a wood burner (very simple) Pellet stoves much more at the mercy of the safety features. Not knowing if some bone head disconnected some safety "he" didn't feel necessary could cost "you" big. Guess the lesson here is "know your stove...especially if its used..... before you buy/ use it"
Great thread!!

 

[SmokeyTheBear]

iceguy4,

Most heating systems are basically the same, just variations on a theme. Fuel in, air in, heat out somewhere in the setup. Pellet stoves are safer than wood stoves in general. But in all cases it is not keeping the units maintained properly that will get you in trouble. Do not assume anything with a used unit always check it out before using. Observe all cautions and warnings in the manual and never short any clearance in the stove manual or the vent makers instructions.

Speaking of which Neilt, about that hopper extension you have asked about, make certain it is certified for use on your stove by the stove maker before you get one let alone attach one. Most such devices aren't and it voids any certifications the stove may have to attach such a device.

Mike Holton (stoveguy2esw) mentioned gaskets not having been talked about in detail as a possible culprit in this case. That is true and several other things haven't been mentioned as well. It is always in one's best interest to pay attention to Mike, he eats, sleeps, and breathes stove failure analysis in order to fix peoples problems with or to refurb England Stove work Stoves.

I'm just trying the high percentage possible causes first.

Bioburner has to face the results of malfunctioning heating devices by fighting the resulting fires.

None of us like to see or hear of any fires caused by heating devices.

 

[Neilt]

I spoke with Lennox a few weeks back (bought whitfield), they informed me there is no approved hopper extension because of the age of the stove.

From what is being said, my opinion is that the air chambers behind the wall are dirty.

 

[Stovensen]

As far as safety switches being bypassed, I am not that familiar with how many are on the stove, but I can tell you that I replaced the low limit switch, and the high limit switch does not look to have been tampered with... As it is an older stove these were the only two safeties I noticed(I am not saying that is all it has).

Hi Neilt, This wiring diagram is a photo I took of the one that is glued to the inside of the side panel of my stove ( just above the control board ) Sorry for the quality, but It's the best I could get, since there is no diagram in the owners manual pdf ( also downloadable below ) It should, however, make it possible for you to verify if everything is wired correctly on your stove, or has been tampered with by the previous owner... very important knowledge!!


Now that was a scary hopper fire you had there... luckily it smoldered out before anything really serious happened to you and your home.
Since I'm also the owner of a Quest Plus, I'm extra motivated to get into depth of finding the reason for this hopper fire and I won't give up until every stone has been turned and examined in order to find a plausible explanation.
The "starve/smother" scenario suggested by Mike Holton in post #15 is a bit scary, as it could happen in my stove too. As well as in many other pellet stoves.
Now, you said that you had too much draft even with the damper fully closed and in your first post about a month ago you stated that the impeller of your combustion blower was different from the one on mine:

I noticed the fan did not look the same as the one I had pulled and cleaned. When I pulled the fan out, there was a mouse that was in the exaust. He must have been in there when I turned it on for the first time. As I said the house was vacant, and I just purchased it. Anyways I finished the rest and it is getting plenty of air now. So now it's off to search this forum again for the fine tuning of the stove. Thanks again to all of you.

Link to this thread: https://www.hearth.com/talk/threads/quest-plus-burn-problem.116427/#post-1567290

Neilt, is it possible that your combustion blower has been changed to a "wrong" type by the previous owner? Please have a look at the pics of mine here, which is the original factory blower from 1998. Is there a big difference??


Note: The amperage of a 120 Volt blower is somewhat higher.

 

[Neilt]

Stovenson,

Thank you very much for the diagram, as mine has been pulled off. I should have corrected myself later in the earlier thread, I pulled the wrong fan the first time, that is why it looked different(I didn't realize it had two). My combustion blower is exactly the same. When I pulled that blower, that is where the mouse was. That was my problem, and it worked fine after that cleaning for the ten bags.

 

[SmokeyTheBear]

Glad you dropped in Bo.

The safeties according to the wiring diagram are the low limit, the two high limits (bet one might be mounted against the pellet drop tube) and the vacuum or pressure switch.

Both high limit switches will stop the pellet feed as will the pressure switch. One some stoves with two high limit switches one is frequently auto reset and the other manual reset, the manual reset in this case is usually called a burn back preventer and is mounted against the drop tube the other one is usually mounted against the heat exchanger.

 

[stoveguy2esw]

tell ya what (im home now and dont have to divide my thoughts between this and what i was doing at work)

here's the dynamic of a burnback in a top feed unit.

essentially you need a couple of things to go wrong at the same time. one of which usually involves the exhaust pathway being stopped up or badly restricted. the other would be a loss of draft or a loss of flame followed by a late stage ignition (from the remaining coals after the draft blower shuts off due to lack of heat.)

in a clean stove with good seals loss of draft usually doesn't do more than occasionally losing a bit of smoke into the house through spots which may not be sealed well or were simply designed by the manufacturer to be open (airwash intakes and holes around scraper rods and such) the reason is that the fuel is not connected to the hopper,

now a stove which is burning dirty tends to mound up fuel and can build a pile right up into the drop chute. then , as the other malfunction occurs you have a fuse leading to the hopper. so the pellets slowly get consumed but as they get to burning in the drop chute the heat transfers up and set the ones in the auger alight.
normally a well sealed hopper will still prevent a hopper fire though as to continue the burning effect "air replacement" must occur (and a sealed hopper prevents this) now, leaky gaskets in say the door or window do not contribute to this as much as they would to the actual piling up of pellets, but a hopper without an effective seal can allow the fire to continue to burn creating almost a "chimney effect" as the heat rises out the leaky top it draws air in through the burn pot and up the feed chute

now, talk about a dirty heat exchanger, when plugged up do not allow free flow of air through the normal pathways and out the vent (having a vertical rise on the vent helps this somewhat if clean or moderately so) with this in mind think about a way heat can move as the pressure in the firebox from heat expansion and no clear way out normally is present. this expansion can push heat through the feed system if not sealed well due to a possible path of lesser resistance.

continued on next post