Help! VC Defiant Encore Catalytic Converter Burning Orange

[Sophie]

We have a Defiant Encore that we bought 20 years ago. We never used it as a primary heat source, and stopped using it completely when we had problems with it backpuffing. We just started using it again this year and intend to use wood heat as well as a newly purchased pellet stove.

Today we had a good bed of coals going and ran it all day with the catalytic converter. Tonight I went over to the stove and could hear a kind of rushing air sound and looked into the stove and it was glowing orange in the back of the stove.

We opened the catalytic converter damper and the griddle temperature eventually heated up to 900 degrees even though we had turned the temperature control to appx. 1/2 open. It is cooling off now.

Although I love wood stove fires, I am really starting to hate this stove - is this something we are doing wrong or is this a problem stove?

 

[Brian VT]

I don't know that stove but either it got too much air or the draft is too strong.

 

[North of 60]

Whats wrong with orange? This means your cat is working just fine.
EDIT If it was just your cat glowing.

 

[North of 60]

What was your t-stat setting before?

 

[Sophie]

It was turned down - we kept the griddle temperature at appx. 500 degrees - it was 1/2 open.

 

[North of 60]

The 900deg is kind of scary. Is the area where your auto damper is clean and free of dust bunnies being an older stove?
Sounds like it was stuck open. :bug:

 

[homebrewz]

It sounds like the stove hasn't seen a lot of use, so perhaps after 20 years of mostly just sitting around, it might
not need a total overhaul? However, at the very least I'm sure it could use all new gasket material on all moving parts:
Double doors, ashpan door, griddle gasket, catalyst access panel, etc.

I have a model #0028 and for mine, most were 5/16" gasket, except for the griddle (5/16" wire reinforced)
and the ashpan door, 3/8". These could be different for your model though.. check your manual.

The optimum range for operating that stove is 450-650.. maybe 700-750 for brief periods, but even thats pushing it.
If it keeps overfiring and going up to 900, first, its not safe, and second, it is going to need a rebuild sooner than later.

 

[Sophie]

We had a stove tech go over it this fall - he put new gaskets on the stove and he looked it over and said it was in good shape - he said he expected problems because of the stove's age but didn't find anything - I don't know how to tell if there is a problem with the damper - is it visible?

 

[Sophie]

There were a lot of coals and I had loaded quite a bit of wood in the stove - I went by the picture in the manual that shows the stove loaded up.

 

[homebrewz]

OK.. well there goes the old gasket theory.

Doesn't sound like the internal damper is the problem, and yes, you can see it quite plainly by looking inside the firebox.

The sound of the rushing air seems may indicate a leak somewhere, but when mine is humming right along,
I can sometimes here a faint howling from the sound of air being taken into the primary air inlet at the back bottom
part of the stove.

Maybe the ashpan door is slightly ajar? There is a screw type adjustment on the handle for a tighter fit. If the ashpan door
is not mating against the stove correctly, it can draw in air that way and turn that stove into a blast furnace.

Maybe try smaller fires until you get used to running it again?

One other thing is perhaps you're just getting too much draft? Could you describe your setup as the pipe leaves the stove?
Do you have an inline damper in the stove pipe? If thats the problem it may help.

 

[North of 60]

What was the stove temp before you opened the bypass? Was the temp OK but you saw the cat glowing so you opened it? Still kinda confused. Sorry for all the questions but this will help you eventually.

 

[Sophie]

We have an 8" flue pipe that is connected to a masonry chimney which was built 20 years ago when we built our house - it's a 2 story cape. It's a 2 flue chimney (1 for an oil furnace and one for the woodstove) of concrete blocks with a ceramic liner and bricks on the outside.

 

[Sophie]

The temperature was ok - I could just hear kind of a faint rushing air sound like maybe a very far off jet sound - you had to pay attention to hear it and figure out where it came from - then we looked at the stove and saw the glow. The temperature was ok at that point, but we then opened the damper and that was when the temperature went up. It eventually cooled off when we shut the temperature control completely down.

 

[Sophie]

The temperature was appx. 500 degrees when we saw the orange glow.

 

[North of 60]

So at that time you didnt have a problem. Cats do glow, mine glows 4-6hrs after a fresh load. I think opening the by-pass caused this. Where is your thermometer located?

 

[Sophie]

The thermometer is in the center of the griddle.

We can't see our catalytic converter - what we saw that was glowing was a cast iron strip at the back of the stove in front of the catalytic converter. We could also hear a faint rushing air noise. Maybe I overloaded the stove and made the fire too big.

 

[homebrewz]

The metal strip is the heat exchanger. Its not cast iron, but is made out of steel. It is there to
help hold the catalyst in place and also to pre-heat it before ignition. Its been my experience
that the heat exchanger will glow during normal operation probably more often than not.
Whether or not this is really an issue, I don't know. Perhaps someone could comment?
The catalyst will normally glow during ignition.

That stove has both primary and secondary air passageways inside of it. Perhaps that is the sound
you are hearing. If the thermostat doesn't seem to control the rate of burn much, then you probably
have some sort of leak, whether it is from a gasket, or a factory seal. If you want to check for that,
light a stick of incense/punk stick and let it go out. Move it around the stove while its in operation and
see if the smoke gets sucked into the stove anywhere besides the primary and secondary air intakes
(both located at the back of the stove).

 

[VTSR5]

A cat that glows is working. But a working cat may not necessarily glow.

 

[Sophie]

We checked the primary and secondary air supplies and vacuumed them - the thermostat handle does work opening and closing the primary air supply.

I'll buy some incense to check for leaks and in the meantime we will make small fires. I think I got carried away and just made the fire too big.

Thanks for the help - it very much appreciated : )

 

[Sophie]

I bought incense and air is being drawn in by the ash pan.

That will get fixed asap.

The incense was a great idea. Thank you again

 

[homebrewz]

Your welcome! So, did the tech replace the gasket on the ashpan door? I believe its 3/8" gasket. If he did replace it, check the alignment
of the door with the mating surface. Also, there is a screw-type adjustment on the ashpan handle that you can adjust to make a tighter fit.

Good luck!