Flue Temp vs Flame

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Fpomes2

Member
Oct 25, 2018
7
CT
Hello all- newer to wood burning inserts and have some questions. I had a Lopi Flush Hybrid-Frye installed on Sunday. So far so good, but I am noticing high catalyst temps with a weak flame. My catalyst temps easy hit 750 (even when choking the fire down) but it barely looks like the fire is going. I am guessing this is due to my wood not being fully seasoned? When I measure the wood it sits at around 18% moisture (when I split a piece and measure the core). The ends of the wood measure around 12%. Also, my glass gets dirty quick. I am using a mix of hardwoods seasoned for a year.

The Large Hybrid-Frye comes with a catalyst probe for temperature. The manual says a "hot fire" is about 600 degrees. At what point is it too hot?

Also, has anyone measured their fan output temps? what should be expected?

Thanks guys!
Frank
 
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Well, my suspension was right. I went out and retested the wood I brought into the house and the core was at 22-24%. The would explain the glass getting dirty so quickly and the poor flame vs catalyst temp.
 
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I am noticing high flue temps with a weak flame. My flue temps easy hit 750

The Large Hybrid-Frye comes with a catalyst probe for temperature.

Thanks guys!
Frank

So are you quoting 750 at the flue or the catalyst?

And split wood needs to be room temperature before measuring the MC.
 
So are you quoting 750 at the flue or the catalyst?

And split wood needs to be room temperature before measuring the MC.

The temp probe should be on the Catalyst correct?... If the catalyst is reading 750 degrees but isn't glowing should I allow the fire to get hot enough so the cat is glowing orange?

Didn't know the wood needed to be room temp, but yes it should have been close to it. I brought it inside hours ago, so it had a chance to warm up before I split it and tested it.
 
The temp probe should be on the Catalyst correct?... If the catalyst is reading 750 degrees but isn't glowing should I allow the fire to get hot enough so the cat is glowing orange?

Didn't know the wood needed to be room temp, but yes it should have been close to it. I brought it inside hours ago, so it had a chance to warm up before I split it and tested it.
Wood need to be inside at least for 24 hrs or more. 750 cat temperature is on the low side. It lights off around 500. What I am seeing here is, you need a little more time and get the hang out of the stove. I am sure many with the same stove will guide you in the right direction.
 
Wood need to be inside at least for 24 hrs or more. 750 cat temperature is on the low side. It lights off around 500. What I am seeing here is, you need a little more time and get the hang out of the stove. I am sure many with the same stove will guide you in the right direction.

You are absolutely correct. I've been experimenting with the burn temps and it appears the stove loves to be at 900-1200 at the cat. Anything below that the flame is low and the wood does not burn well. If I have the insert burning with the cat temps at those levels the stove puts out great heat and I am not seeing any signs of "overfiring".

The other stove I have been using in our VT house is the Napoleon EPI3C. That stove I do not need to monitor the heat as much. Plus the wood I have in VT has been aged much longer.

Thanks for letting me vent and think out loud.
 
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You are absolutely correct. I've been experimenting with the burn temps and it appears the stove loves to be at 900-1200 at the cat. Anything below that the flame is low and the wood does not burn well. If I have the insert burning with the cat temps at those levels the stove puts out great heat and I am not seeing any signs of "overfiring".

The other stove I have been using in our VT house is the Napoleon EPI3C. That stove I do not need to monitor the heat as much. Plus the wood I have in VT has been aged much longer.

Thanks for letting me vent and think out loud.
Read again the manual, possibly they are talking about stove top temperature? That sounds more adequate, or 600 the light off temperature of the cat to close bypass or whatever do the switch to cat mode? I am not familiar with that model, just assuming.
 
I did a little reading and if I understood correctly the manual mentioned hot fire around 600 for the second part of the brake-in fire. I really think they talking about stove top temperature. The probe is to know when the cat is at 500 and you can close the bypass.
 
I did a little reading and if I understood correctly the manual mentioned hot fire around 600 for the second part of the brake-in fire. I really think they talking about stove top temperature. The probe is to know when the cat is at 500 and you can close the bypass.

yeah you are probably right. From everything I've been reading about a catalyst, they can go up to 1600 degrees and can comfortably operate at 1000-1200 degrees.

last night I was keeping the cat at 1100 or so and the stove ran great all night. No soot on the glass and had a beautiful flame all night.
 
And this was why I asked did you mean flue in both places or did you mean catalyst.

I see now you corrected the original post. Thanks, for later on search results.
 
it appears the stove loves to be at 900-1200 at the cat. Anything below that the flame is low and the wood does not burn well. If I have the insert burning with the cat temps at those levels the stove puts out great heat and I am not seeing any signs of "overfiring".
I can burn my stove low with no flame, yet the cat is still glowing..with Red Oak that's been split and stacked for several years. I'll burn with a little flame in the box if I want more heat. With your marginally-seasoned wood, your may have to "burn in" a new load longer to get rid of the additional moisture, then you may be able to get a good cat-only burn, no flame.
 
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