Advice On How to Use the Cat Properly

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Raddler

New Member
Oct 16, 2023
5
Maryland
Hi All,

I just purchased a Regency i2500. Love it so far, I’m only about 6 fires in. I have some questions about when to use the cat. I usually do a top-down start, wood is blazing and the thermometer that came with the stove is reading about 600 within 15-20 mins. Usually, the blower kicks on around this point and the temp drops to the 450 range within 10-15 mins. I find that I really have to keep a strong fire going to stay above 500 once the blower is on. It hasn’t been that cold yet so I’m usually throwing 2 or 3 splits in every few hours to keep in this range. I find myself constantly engaging and disengaging the cat as the temp rises and falls. So, looking for some advice on when to use the cat. Should I forget it for now and only use it once its cold enough to be fully packing the stove once or twice each day? I’ve read some people say to engage for over night but surely there will be a few hours window of below 500 for an overnight burn. So, when do you use the cat?


I’m burning 3 year seasoned oak.
 
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The cat does not need to be disengaged when the fire burns down overnight. Once the fire is at the coals only stage the wood has stopped outgassing and no volatiles are left to make smoke. The CO and CO2 will just pass through the cat with no harm.
 
I've had some weather recently for a little more testing. I'm still really struggling trying to understand how to properly use the cat. With a full load blazing, once that blower kicks on, the temp drops to around 600 rather quickly. I engage the cat, but the temp continues to slowly drop over the next hour or two usually hovering around 400. I could maybe keep the temp higher by giving it full air but then the fire is blazing, with flames licking the cat. I was under the impression that when using the cat I'm trying to let a fire smolder but the temp should stay above 500. I'm finding that a difficult state to achieve. Am I missing something?
 
I may be wrong and hopefully someone will correct me. It’s my understanding that the cat needs a temp of 600 to engage but once engaged it will work at lower temps than the startup temp.
I’ve just recently replaced my older stove with the same one you have and like it so far.
 
I have CI2700/Hi500. Last winter was my first. I started mid November and ran it 24/7 until mid March. I would fill 3 times per day at 8am, 4pm and 11pm. I would open bypass and draft control 100%. When it looks like the first is stable and strong, I would close both completely. This would give me about 8 hour burn. I have the fan set to AUTO and LOW. It would kick in sometimes around 600, sometimes as high as 800. I never turned it off. Temps would drop when fan kicks in, but could go as low as 200 I think before it auto turned off. Next time I need to load, I open bypass and draft control, turn off fan if it was on (rarely ever on at that point), open door and put a few small piece in to see if it would take, then load it up once it's going well. Rinse, repeat.
Like I said, I never touched the fan and let it do it's thing. I am in a ranch, about 1600 square feet. My living room would hover around 76 and sometimes hit 80. Back of house 70-72. I have a ceiling fan in the dining room which dispersed the heat all over. Without the ceiling fan, all the heat would be at the ceiling and living room was probably around 70, but back of house was mid 60's. Ceiling fan did wonders. First time I turned it on, walked up from basement and WOW, it's so hot!
I thought my first year would be a learning experience and it would be my test season, but I went 24/7 for the 4 months of winter weather here in NY.
 
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Correct me if I'm wrong, but doesn't the i2500 come with a digital probe that measures flue temperature? Which would give a much lower temperature than off the cat itself?
 
I have CI2700/Hi500. Last winter was my first. I started mid November and ran it 24/7 until mid March. I would fill 3 times per day at 8am, 4pm and 11pm. I would open bypass and draft control 100%. When it looks like the first is stable and strong, I would close both completely. This would give me about 8 hour burn. I have the fan set to AUTO and LOW. It would kick in sometimes around 600, sometimes as high as 800. I never turned it off. Temps would drop when fan kicks in, but could go as low as 200 I think before it auto turned off. Next time I need to load, I open bypass and draft control, turn off fan if it was on (rarely ever on at that point), open door and put a few small piece in to see if it would take, then load it up once it's going well. Rinse, repeat.
Like I said, I never touched the fan and let it do it's thing. I am in a ranch, about 1600 square feet. My living room would hover around 76 and sometimes hit 80. Back of house 70-72. I have a ceiling fan in the dining room which dispersed the heat all over. Without the ceiling fan, all the heat would be at the ceiling and living room was probably around 70, but back of house was mid 60's. Ceiling fan did wonders. First time I turned it on, walked up from basement and WOW, it's so hot!
I thought my first year would be a learning experience and it would be my test season, but I went 24/7 for the 4 months of winter weather here in NY.
What is the highest temp your probe reaches after engaging the Cat. I've got an Hi500 and i'm having overfiring issues and i run the stove identical to what you stated.
 
What is the highest temp your probe reaches after engaging the Cat. I've got an Hi500 and i'm having overfiring issues and i run the stove identical to what you stated.
After engaging the cat, I have hit as high as 1100 degrees sometimes, but generally under 1000. Do you have the fan with yours? If the fan come on right away, it will keep the temps down around 700. If it doesn't kick on until later, it can hit that 1100 degree mark.
The times I get the highest temp is probably when I have the most dense wood and am able to fill up all the space. You know, it's like a puzzle sometimes. You get a large piece in the back and you can't quite get another full piece on top of it, so you have to use a smaller piece. A very dense pack get the temp up.
What temps are you hitting after turning on the cat?
I "think" I am doing everything right as I never got real world instructions from anyone other than what was included with the unit. My stove cleaner said I had very little creosote up the flue and my cat was in superb condition. Only one year though.
 
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After engaging the cat, I have hit as high as 1100 degrees sometimes, but generally under 1000. Do you have the fan with yours? If the fan come on right away, it will keep the temps down around 700. If it doesn't kick on until later, it can hit that 1100 degree mark.
The times I get the highest temp is probably when I have the most dense wood and am able to fill up all the space. You know, it's like a puzzle sometimes. You get a large piece in the back and you can't quite get another full piece on top of it, so you have to use a smaller piece. A very dense pack get the temp up.
What temps are you hitting after turning on the cat?
I "think" I am doing everything right as I never got real world instructions from anyone other than what was included with the unit. My stove cleaner said I had very little creosote up the flue and my cat was in superb condition. Only one year though.
I do have a blower and i turn it on manually until it get hot enough to run on auto. This last load i ran got up to 1200 degrees with the cat engaged and the fan on high. the flame shield that covers the front of that cat started to glow red so I had to disengage the cat to get the temps back down below 1000 degrees. Even with the cat disengaged it will still glow red which to me seems wrong. I'm in the same predicament with the instructions. The dealer who sold it to me basically says i'm the only one with this issue so it must be my fault.

20240113_184918.jpg 20240113_184949.jpg
 
I think the cat cover glowing red is normal. I think that signals that it is hot enough to start burning the gases and smoke. I have seen 1200 also. I said 1100, but an occasional 1200 too. If you want to keep the fire a little less hot, maybe one of two less pieces of wood. How long do you go before filling up again?
 
I do have a blower and i turn it on manually until it get hot enough to run on auto. This last load i ran got up to 1200 degrees with the cat engaged and the fan on high. the flame shield that covers the front of that cat started to glow red so I had to disengage the cat to get the temps back down below 1000 degrees. Even with the cat disengaged it will still glow red which to me seems wrong. I'm in the same predicament with the instructions. The dealer who sold it to me basically says i'm the only one with this issue so it must be my fault.

View attachment 322708 View attachment 322709
How tall is the flue liner on this insert?
 
Correct me if I'm wrong, but doesn't the i2500 come with a digital probe that measures flue temperature? Which would give a much lower temperature than off the cat itself?
The cat is directly under the flue outlet so that probe is pretty accurately measuring cat temps. And yes that heat is then wasted up the flue
 
That's tall enough to make for very strong draft in cold weather. The air intake may need restriction. There should be a restrictor plate in there now but it may need a little more.
 
That's tall enough to make for very strong draft in cold weather. The air intake may need restriction. There should be a restrictor plate in there now but it may need a little more.
That's what i was thinking. Do you have any suggestions? I made up a perforated baffle today that fits into the trapezoidal shaped shroud covering the air inlet on the front of the stove. Hoping to dissipate that "rocket" effect when at the low air control setting. I suppose i could try and find the air openings on the outside of the stove and try covering them slightly.
 
That's what i was thinking. Do you have any suggestions? I made up a perforated baffle today that fits into the trapezoidal shaped shroud covering the air inlet on the front of the stove. Hoping to dissipate that "rocket" effect when at the low air control setting. I suppose i could try and find the air openings on the outside of the stove and try covering them slightly.
Do you have the Draft Control all the way to the right (closed)?
 
Do you have the Draft Control all the way to the right (closed)?
That's what i was thinking. Do you have any suggestions? I made up a perforated baffle today that fits into the trapezoidal shaped shroud covering the air inlet on the front of the stove. Hoping to dissipate that "rocket" effect when at the low air control setting. I suppose i could try and find the air openings on the outside of the stove and try covering them slightly.
yes draft control is all the way right. I made a baffle for the air outlet on the inside of the stove. I cut out a template on 3/16 thick steel and drilled a pattern of 3/16 holes and it has help tremendously when the stove gets up to temp. I'm also loading one piece of wood left to right in front of the air outlet and then the rest of the load front to back. Thanks for the help all.
 
yes draft control is all the way right. I made a baffle for the air outlet on the inside of the stove. I cut out a template on 3/16 thick steel and drilled a pattern of 3/16 holes and it has help tremendously when the stove gets up to temp. I'm also loading one piece of wood left to right in front of the air outlet and then the rest of the load front to back. Thanks for the help all.
I am trying to picture this. What air outlet inside the stove? Don't you have a nice ash base built up in there that you cannot get a wood piece low enough to cover any air outlet? I might just be misunderstanding.