New combustor too tight for installation in Blaze King

[CCwoodburner]

Good day, All.

Heading into wood burning season, I'm wrapping up a bit of a refurb on my Blaze King Princess Insert (PI 1010A). The BK is the main heat source in my single level 1400 sq ft home, backed up by central heat - During the cold winter months, the BK is typically burning 24/7. I grew up with non-cat wood heat, and I have been very impressed with the Blaze King experience so far. I recently pulled the insert from it's home in the fireplace area to clean accumulated soot from above the block off plate, replace the bypass gasket (which was completely compressed), I'll replace some damaged fire bricks, and the big ticket item is replacing the combustor with a new Midwest Hearth metal combustor (model MH-63M).

The BK is back in final position and I'm trying to install the brand new metal combustor to complete the refurb... I CAN NOT GET THIS SUCKER PUSHED INTO PLACE. I've installed the new interam gasket using single layer masking tape, including around the four sides of the inside edge, to avoid letting the gasket material from snagging during installation. The metal frame/dome is completely clean and free of deposits... very smooth to the touch. This model has the thin bypass retainer clips on the left and right sides and are properly installed. Comparing measurements of the original ceramic combustor and the new metal one, there is no notable difference - the new one doesn't seem too big or out of shape. I've made multiple attempts to press the new metal combustor into place and there's just way too much friction. Using my hands, I've strained trying to press it evenly into the dome frame, but can only make it about 3/4" until it's stuck. I carefully pull it back out, fix the tape and puckering edges of the gasket. What am I missing? Any pro tips to get this new combustor seated? I wasn't expecting it to be so tight.

Thanks for any recommendations!

 

[EatenByLimestone]

I’m not familiar with the stove, but I’ll give it a shot.

Is the gasket too thick? Was it supposed to be cut to length and sent long so it could be used in multiple stoves/designs?

 

[CCwoodburner]

I’m not familiar with the stove, but I’ll give it a shot.

Is the gasket too thick? Was it supposed to be cut to length and sent long so it could be used in multiple stoves/designs?

Thanks for the response.

Standard interam gasket material. Normal thickness (approx 1/8” thick, or less). The gasket is 2 inches wide, which matches the width dimension of the combustor. Length was trimmed to have the gasket cleanly wrap around me the outside frame of the combustor (with no overlapping/doubled-up portion).

 

[EatenByLimestone]

I found a new video showing cat replacement in a Princess. Hopefully it helps.

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[CCwoodburner]

Thanks for posting the vid…. I’ve seen that one. That’s the stove I have (insert version). In the video you can see the interam gasket neatly wrapped and taped around the new combustor. His new combustor easily slides into place with mere fingertip pressure… mine is very tight and can barely make it into the rectangular hole 3/4”. I’m perplexed as to why mine is so tight going in. The old combustor pried out no problem (other than the normal friction you’d expect).

 

[stoveliker]

I suggest to post a pic of how the slot looks, how the parts are situated.

 

[CCwoodburner]

I’m away from my wood stove at the moment, but here’s a shot from the Princess manual… and a pic of my new combustor.

 

[stoveliker]

Yes. But I think it'd be good to get a pic of your situation once you are there.

 

[moresnow]

Did you get the gasket from Midwest H. ? If not I believe there is an incorrect thickness material out there. !/16th is correct. Believe I have seen 1/8th for sale elsewhere. Have you tried the old cat with the new gasket to verify? Something to consider. Good luck!

 

[CCwoodburner]

Did you get the gasket from Midwest H. ? If not I believe there is an incorrect thickness material out there. !/16th is correct. Believe I have seen 1/8th for sale elsewhere. Have you tried the old cat with the new gasket to verify? Something to consider. Good luck!

Yep- the gasket came with the combustor from Midwest Hearth, and certainly looks like the right thickness.

I’ll snap some photos when I get home.

 

[moresnow]

Yep- the gasket came with the combustor from Midwest Hearth, and certainly looks like the right thickness.

I’ll snap some photos when I get home.

Okydoky.

 

[CCwoodburner]

Here are some pics of the new combustor and gasket, the dome area, and as far as the combustor will go in before getting too tight to push in further.

The gasket is not doubled up, or getting snagged nor binding up.

 

[Todd]

I wonder how it fits without the gasket? I’m not sure but I thought you only needed a gasket for ceramic cats that don’t have the metal can attached? Maybe PM BKVP.

 

[Highbeam]

I wonder how it fits without the gasket? I’m not sure but I thought you only needed a gasket for ceramic cats that don’t have the metal can attached? Maybe PM BKVP.

Ugh, there was one metal cat seller claiming that you didn’t need a gasket with their steel cat. You need a tight seal and BK designed the stove to do that with a gasket and a certain dimension cat. It is possible, and perhaps what we’re seeing here, that some steel cats are now being built oversize in an attempt to provide a tighter fit and eliminate the need for a gasket.

I don’t like steel cats. The oem ceramics from Midwest hearth have always fit great for me with the supplied pre installed gasket.

The steel cats from Midwest hearth…. Has anybody explored their manufacturer? Is it the same as what BK uses as oem? If, a big if, it can work out gasketless that would be awesome.

 

[BKVP]

Your old combustor frame is still in the stove! You must remove it.

I wonder how it fits without the gasket? I’m not sure but I thought you only needed a gasket for ceramic cats that don’t have the metal can attached? Maybe PM BKVP.

 

[BKVP]

Sorry, those are retainers.

Your old combustor frame is still in the stove! You must remove it.

It should fit...

 

[CCwoodburner]

Sorry, those are retainers.

It should fit...

Yep- those are the retainers on the left and right side of the dome.

Well, I got home and managed to successfully get the new metal cat in (!). It’s cold here and I was determined to get a fire going. I gave it one more attempt with the standard configuration and it was a no-go, only sliding in 3/4” using a lot of force (what you see in the pics above). I had to try something new.

To respond to some of the recent replies… this metal cat and the BK are designed to be used with a gasket. For the sake of ruling out an oversized cat from the manufacturer, I removed the interam gasket just to test fit into the opening- it slid right in no problem. To me, that proved that it was the interam gasket that was ultimately binding it up. While the gasket was removed from the cat, I literally rolled it out on a flat surface with a heavy rolling pin to slightly reduce the thickness of the spongy gasket material, re-trimmed it and reinstalled on the cat… and voila! It slid right in no problem with fingertip pressure. A little rolling pin action was all it needed! It was a night n day difference in fitment pressure between the gasket at standard thickness vs squishing it out just a bit with the rolling pin.

The BK is happily burning along now with new cat in place. THANKS for all the replies, info, and help for such a random, unforeseen issue.

 

[begreen]

But of course, the kitchen cure. Well, at least you didn't have to lube it with some mayo.