7-8 weeks before I need to pull cat for cleaning.

[clydesdale]

This is my 9th year running this insert. It is a large hybrid fyre insert. I used to destroy cats and have since switched to steel. But, these cats do start plugging up on me after about 7-9 weeks.

I now have 2 cats so that I can do a quick swap and clean at my leisure. I have a 32 ish foot liner. I have painted five marking lines on the air adjustment. 5 lines is fully choked. I usually run the stove between 3 and 4. If I run it at 1 or 2, the flames will lick the cat. I made a metal mesh to protect the cat a bit. I think some of my issue might be that I get the fire going again at 6am and by 6.40 and back it down to line 4 and walk out the door. Maybe that is causing a build up. Maybe I gotta run less wood, but more air flow to clean it out. Any thoughts? You would think I would have this all figured out by now. I have learned to use steel cats and have also learned many people could never own this stove. Many people would not be able to swap cats every 2 months.
Please advise. Thanks.

 

[stoveliker]

You have too much draft sucking the ashes (and flame) in the cat, clogging (and destroying) it.

You need to decrease your draft. A key damper would be the advice for a free standing stove. For an insert this is hard but not impossible.

 

[icestationzebra]

I clean my cat every few weeks during the winter. I use a can of compressed air on the cat when it is cool (only when the fire is burnt out and only when the cat is cool to the touch). It only takes a few seconds and a can of compressed air usually lasts me a couple of years.

 

[clydesdale]

I do now recall being told the draft was too strong before. Thank you for that reminder. I am not sure how to add the key damper. The previous fireplace had damper, so there is a hole in the masonry about 18 inches above the bypass slide handle for the cat.

As far a cleaning. I hit it with an ash vac and a car detail hose/brush everyday when I get home from work. I then get it fired back up. So, I feel like I am maintaining it the best I can. I thought I heard that a compressed air can is too powerful and can damage the cat. I could be wrong on that.

 

[stoveliker]

Vacuuming is safer than blowing indeed.
If there is a hole that's good. Is not necessarily easy though.

 

[icestationzebra]

I use the can of compressed air from a distance of about 12" from the cat. The certified installer recommended it to me when we first installed the stove almost a decade ago and I've been doing it ever since. I can't see the air producing enough pressure to damage anything but maybe i'm missing something.

 

[moresnow]

Any options for reducing the incoming air instead of a downstream damper? Cover/plug some of the air intake with a magnet or tin foil perhaps. Believe I would exhaust that route before moving ahead. A thought.

 

[stoveliker]

I clean my cat every few weeks during the winter. I use a can of compressed air on the cat when it is cool (only when the fire is burnt out and only when the cat is cool to the touch). It only takes a few seconds and a can of compressed air usually lasts me a couple of years.

btw, compressed air cans often do not contain (only) compressed air.
Sometimes they contain hydrofluorocarbons, and halogens (fluorine) are known to adhere to active sites in catalysts. Not as much as other elements, but some.

Barring better knowledge (which may or may not exist out there for this particular type of catalyst, and I don't have the time to search), I would avoid using materials of which you don't know how they might affect the cat. Even if it's occasionally rather than continuously.

Maybe @Tron knows more.

 

[Tron]

Maybe @Tron knows more.

Actually, I do.
There's two types of "compressed air" sprays: flammable and non-flammable.
The flammable (cheaper) type contains almost exclusively hydrocarbons, think propane/butane.
The non-flammable also need a liquid that evaporates to make a gas, so hydrofluorocarbons are a pretty good bet.
In fact, I just looked up the SDS for one, and it contains 1,1,1,2-Tetrafluoroethane (98- 100%), which is basically the refrigerant R134a.
However, those are rather volatile (they kinda have to be) and spraying them on a cold cat is not going to harm it. Those compounds are pretty stable, chemically speaking, but I wouldn't spray them on a hot cat. That might actually affect the cat, but the main issue would still be the thermal shock.
So spray away on your cold cat, it's not going to hurt it. By the time you fire it up again, the gases are long gone.

 

[stoveliker]

Ty!

 

[EbS-P]

A key damper can be installed in the appliance adapter. The surround must be drilled and the handle extended it a universal joint.

 

[icestationzebra]

Actually, I do.
There's two types of "compressed air" sprays: flammable and non-flammable.
The flammable (cheaper) type contains almost exclusively hydrocarbons, think propane/butane.
The non-flammable also need a liquid that evaporates to make a gas, so hydrofluorocarbons are a pretty good bet.
In fact, I just looked up the SDS for one, and it contains 1,1,1,2-Tetrafluoroethane (98- 100%), which is basically the refrigerant R134a.
However, those are rather volatile (they kinda have to be) and spraying them on a cold cat is not going to harm it. Those compounds are pretty stable, chemically speaking, but I wouldn't spray them on a hot cat. That might actually affect the cat, but the main issue would still be the thermal shock.
So spray away on your cold cat, it's not going to hurt it. By the time you fire it up again, the gases are long gone.

thank you, much appreciated. I only use the compressed air very sparingly.... maybe once a month during heavy burn season..... and I only use it on a cold fireplace. but the broader understanding you provided is helpful and knowledge like that is always welcome.

I've always used FPX OEM cats.... which I believe are a mix of ceramic and precious metals. I'm going to finally switch to aftermarket steel when my current cat needs replacement.

 

[stoveliker]

The ceramic is the substrate onto which (an oxide layer and) precious metals are deposited. The latter are what make things work.