NexGen Wood Insert - Missing Cat Combustor?

[TangoDown]

Hi all,

I recently picked up a NexGen Hybrid wood stove insert off Facebook Marketplace and installed it about 2–3 weeks ago. I’ve been burning with it regularly since then. My previous stove was an Avalon Pendleton, so I was expecting this to be a decent upgrade, but so far I’m not overly impressed with the heat output. It feels like I’m going through more wood than I should be, especially for a newer, modern catalytic stove.

I’m running into a couple of issues. First, toward the end of the night I’ll reload the firebox with wood over a good bed of coals and then close the air control down to about 90–95%. When I do this, I’ll only get about an hour to an hour and a half of secondary burn before the firebox fills with smoke.

I’ve gone through the manual quite a bit and can’t seem to find where the actual catalytic combustor is located in the stove, which brings me to my second concern. The manual shows a part called a “combustor retainer,” but my stove doesn’t appear to have this part at all.

Here’s a link to the part I’m referring to:

NexGen-Hybrid Combustor Retainer 250-05858

NexGen-Hybrid Combustor Retainer 250-05858

rockymountainstove.com

Is it possible that the stove I picked up is missing the catalytic combustor altogether?

For reference: the first five photos are of my stove, the sixth photo is from the manual showing basic maintenance, the seventh photo is the part linked above that I believe may be missing, and the last photo shows the stove cruising with a hot bed of coals

Thanks in advance!

 

[begreen]

It does look like the cat is missing. What is the year of this insert? The earlier versions of the Large Hybrid did not have this retainer.

 

[TangoDown]

It does look like the cat is missing. What is the year of this insert? The earlier versions of the Large Hybrid did not have this retainer.

the tag on this stove appears to be manufactured in June of 2021.

Begreen, I must say it is an honor to have you reply to this post lol. I’ve referred back to this forum a lot when I first started burning with my Avalon. You’ve been a lot of help!

 

[bigealta]

Looks like the cat (combuster) goes right in the open space above the secondaries, as shown in the link.

Wood | Made in USA | Lopi Stoves®

NexGen-Hybrid™ Wood Burning TechnologyNexGen-Hybrid™ is a wood burning technology that combines the best of two worlds: the clean burning efficiency of a non-catalytic stove and the greater heat output of a catalytic stove. This advanced system drafts and operates like a super clean...

www.lopistoves.com

 

[bigealta]

I think you have a different stove model, not a hybrid.

Look at the number of secondary tubes, there are only 2 in the hybrid as shown in the link.

Your label says Model: LG Flush Wood.

 

[bigealta]

So if you have a non cat version, why are you not getting the heat out of it?
Maybe this non cat insert is not much/any better than what you just replaced?

But your description of 1 1/2 hours of secondary burn that then turns to smoke seems a bit strange? maybe you need to give it a bit more draft.

 

[bigealta]

Was the avalon an insert or a free standing woodstove?

 

[begreen]

I think you have a different stove model, not a hybrid.

Look at the number of secondary tubes, there are only 2 in the hybrid as shown in the link.

Your label says Model: LG Flush Wood.

Yes, you are right. I was perplexed by this too. This morning I dug a bit deeper to jog my memory. Lopi briefly had a NexGen version of the medium and large flush inserts that were non-cat. IIRC this was just for a few years. It's odd, because the original Large Flush insert was a hybrid with cat. Then in 2020 the cat was dropped. I suspect the first NexGen series was just to pass the test for the EPA changes. This was tested with cord wood. Apparently, the cat returned in order to qualify for the tax credit. Later testing was with crib wood and showed an efficiency gain fron 73% to 78% according to the EPA data.

 

[Slimdusty]

I think this is the nex gen fyre model, not nex gen hybrid. Fyre models did not have catalytic combustion

 

[begreen]

I think this is the nex gen fyre model, not nex gen hybrid. Fyre models did not have catalytic combustion

Yes, that brief period made for some confusion in hindsight. The earlier large, flush models were hybrid-fire, but they didn't call them NexGen until about 2020.