Regency i2500 Catalytic combustor question

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Glassmelter

New Member
Feb 27, 2022
1
Wisconsin
We recently had a Regency i2500 professionally installed and I have some questions about the catalytic combustor that I was hoping you all might be able to help me with.

We're in Wisconsin, so all temps are in Fahrenheit, and we're using fully seasoned oak as our fuel source, in case it helps.

In regard to using the catalyst, I understand that the insert probe should be reading at or over 500 degrees (F) before engaging the catalyst. We really need to have a roaring fire for the probe temp to even start to get near 400, so to get it to 500 seems to take a lot of fuel and time to reach. Is this normal?

Now my real question is, once I have a good coal bed, I load the stove fully, and leave the draft fully open to get the probe to read over 500. Once I have it reading 500, and engage the catalyst, it sounds like I want to leave it in that temp area for at least 30 minutes. To do that, I seem to need to keep the insert going at full draft. However, once a half hour is up, do I need to keep the draft open to maintain those temps, or is the catalyst self sustaining, and I can close the draft a bit and let the temp that the probe is reading fall?
 
I don't have your stove but I do have a cat stove.

How long does it take to get to 500 F on a cold start?

Once the cat is engaged, you should be able to keep it engaged without much trouble as it'll generate heat.

How tall is your chimney? (Too much heat exiting because too much draft?)
Are you sure your bypass closed/seals properly (no heat escaping there)?
How do you know your wood is dry enough?

In principle, decreasing the air after the cat is engaged should result in a hotter cat because decreasing air will make more smoke - which is the fuel for the cat.
 
From a completely cold start, I think it's taken me up to 20 minutes to get the cat probe up to temperature, but usually it's not that long (it's a soapstone stove, so it soaks up the heat). I'd say if it's been 14 hours or less since the last reload, it will take 5 - 15 minutes to go from no fire to cat probe at 500. Check your manual, but I don't think you'd normally want to run with the air all the way open and the cat engaged - I close mine down halfway when I engage the cat. Depending on stovetop and room temps, I might leave it that way for 5 - 15 minutes (I think of this is running on 'high') before closing it down to 25% ('medium'), and for overnights I'll close it all the way down. The cat is self-sustaining with enough smoke, and it's generally more efficient at lower air intake settings.
 
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Congratulations on your purchase!

I own the Regency i1500, so I assume you are using the same Regency branded digital probe thermometer included in my installation.

This winter, I am burning both kiln-dried hardwood and 3-4 year seasoned oak.
I usually fill the firebox box 1/4 full on initial start-up. In my experience, from a top-down burn, it takes 5 - 15 minutes to achieve a probe temp of 500 degrees. I engage the catalyst at 600 or so and cut the air intake in half. From this 1/4 full load, the probe temperature reaches about 1000 degrees and drops somewhat quickly to 9- 700 degrees.

Once I have a good coal bed and the fan turns on, I load the stove fully and leave the draft wide open. The stove warms fast, with the probe temp reaching 500 degrees in five-ten minutes. Once the probe hits the temperature, I engage the catalyst and cut the air in half. Over the next twenty or thirty minutes, I slowly turn the air all the way down.

At this point in the process, on average, the probe temperature won’t fall below 500 degrees for three hours, with the high temperature being 1400.

Did you test the oak’s moisture?
Is it below 20 percent?

I know it seems like those are usually the first questions asked on this forum if a user is having an issue with their stove. The reasoning is valid. It’s easy to test, easy to fix and is usually the cause of most issues.
 
I am having a similar issue. Same Stove. I get the stove warmed up and a good coal base going. Probe temp gets to over 700. I load logs into the box and keep the air fully open for 15 min then close the air down. The probe temp drops steadily. Not quite sure what I am doing wrong. New to burning wood so only my second fire, but the probe temp drop has occurred on both burns.
 
My last couple burns I've had an issue with the cat probe going from 900-1200 to suddenly climbing to HI - it'll stay HI (on probe) for 15 or so minutes then go back into the 900-1200 range. This is going from a cold insert. This has been happening during forearm to arm/leg sized pieces. Has anyone else noticed this? And if so what has been done to remedy?

I start my fires with brown newspaper/tinder and finger kindling (6-10 pieces) then add more finger kindling then add forearm, etc

TIA
 
I am kinda new to this whole thing.. The only thing I can think of is that you are over-firing the stove for a brief period of time. Do you have the door fully closed or open a crack.? If it is open, maybe close it fully after that probe get up to around 900.
 
Door is fully closed. With air intake fully open. I'm looking for glowing within and its not glowing. This afternoon at 3pm the probe was reading HI (after many hours of it reading within an expected 600-800 range) even though it it only had red coals left. I've contacted the dealer to see if they have an answer and I'll let you know. Something makes me think that the probe is faulty.

Also regarding your question "I am having a similar issue. Same Stove. I get the stove warmed up and a good coal base going. Probe temp gets to over 700. I load logs into the box and keep the air fully open for 15 min then close the air down. The probe temp drops steadily. Not quite sure what I am doing wrong. New to burning wood so only my second fire, but the probe temp drop has occurred on both burns."

They said it is normal for the probe temp to drop a little. Are you closing the air slowly or quickly? I've found that if I go from fully open to low it'll cause a drop in temperature. What I've been doing is the following. Let it ripe for 15 or so minutes (turn on fan) and then slowly close down over 20 or so minutes. So I'll go from high to medium high another 5 minutes pass I'll go to medium another 5 min go medium low then finally low. Does this make sense? That seems to allow temp probe to stay within the range I had been it was fully open.
 
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I don't know your stove or your probe. It could be faulty indeed, from what I read.

BUT, a cat does not need to be glowing to be active (to be doing its job). So if you're looking for glowing as confirmation that it's working - that's not the right "piece of data" you need for that.
 
I don't know your stove or your probe. It could be faulty indeed, from what I read.

BUT, a cat does not need to be glowing to be active (to be doing its job). So if you're looking for glowing as confirmation that it's working - that's not the right "piece of data" you need for that.
I meant glowing as in adverse glowing within the stove. I called regency a couple months back to inquire about the upper range of probe temp and they said "as long as it isn't glowing" you should be OK.
 
ok. I'm not sure I'd agree, but again, i don't know this stove well.
My cat glows often. And it's fine. Maybe this is different.
It's of course true that if it's not glowing, it's surely not being too hot.
 
ok. I'm not sure I'd agree, but again, i don't know this stove well.
My cat glows often. And it's fine. Maybe this is different.
It's of course true that if it's not glowing, it's surely not being too hot.
I think they want to cover their a** so someone can't come back and say you caused x,y and z. I looked into the upper range temperature tolerance of a cat. converter and according to the State of Alaska it's somewhere around 1800 - 2000 F which is pretty friggan hot.

Then I read this on a FAQ on a midwest hearth "It should be noted that the combustor glows during the first 20 — 30% of the burn cycle, when the catalyst is receiving the most smoke and burning at a high temperature. The combustor can reach 1000°F and produce a glow. The combustor does not have to glow to be working."


So I would have to agree if you. That a glowing cat isn't going to be a bad thing all of the time. Do you monitor cat temp and stove temp?
 
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On my BK, I don't monitor the cat temp. I do have a gauge that BK put on there, but it has no numbers, just an "active" and "inactive" range. We are instructed to only use it when to use the bypass (engage the cat).

I think 1400 F would be the max if a cat is to be long living.

I don't monitor stove temps either. I do have a flue probe.

I do have a thermocouple that I have stuck and am sticking all over the stove, just for my pleasure. (I like measuring, data.)
 
On my BK, I don't monitor the cat temp. I do have a gauge that BK put on there, but it has no numbers, just an "active" and "inactive" range. We are instructed to only use it when to use the bypass (engage the cat).

I think 1400 F would be the max if a cat is to be long living.

I don't monitor stove temps either. I do have a flue probe.

I do have a thermocouple that I have stuck and am sticking all over the stove, just for my pleasure. (I like measuring, data.)
Awesome - thanks. I spoke with the dealer today and they are going to call regency and ask for a new temp probe. They believe the probe is faulty.