Stoves Specifically Approved for 5.5" Flue

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Joy128

New Member
Jan 5, 2018
4
New Hampshire
Hi All!

Unless we want to tear out a clay liner, we have to use a 5.5" flex flue liner. I've been browsing around lots, and found many helpful articles about folks that have successfully used 5.5" liners with 6" collars (especially if the internal vent measurements are already 5.5" anyways).

HOWEVER in our situation, we're being asked to only install a stove that is specifically designed/approved for 5.5" flues (must state so in the manual). So far the ONLY brand I've found that states that it can accept a 6" AND 5.5" flue is the Regency stoves. They seem to be pricier stoves, and there are few if any on the used stove market.

Does anyone know of any other stove brands that are designed or state in the manual that they will work with the 5.5" flue?

Thanks!

P.S. Oh, and we are hoping to heat about 1200sqft, and want roughly 45,000 btus or higher, so none of the mini stoves ;-)
 
I've installed Regency, Pacific Energy, Quadrafire, Avalon as well as Englander and US stove and the like. The "pricier" stoves are for the most part, better built and do a better job and have a better warranty program. That being said, if the homeowner doesn't know what they're doing it doesn't matter what kind of stove they have.

As for the 5.5/6 inch thing - I know Ahren's makes an adapter for their liners so that a 5.5 liner has a 6" connection to the appliance and I've seen a few. The bigger question would be - If you're relining the flue have you checked it's current condition? Virtually all liners going into a chimney serving a solid fuel appliance are required to have insulation around them if there is any issue with the terra-cotta liner. That includes cracks and open mortar joints. IF you have to insulate it's highly likely the tiles have to come out and then it doesn't make much difference if it's 5.5 or 6 inch.
 
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I've installed Regency, Pacific Energy, Quadrafire, Avalon as well as Englander and US stove and the like. The "pricier" stoves are for the most part, better built and do a better job and have a better warranty program. That being said, if the homeowner doesn't know what they're doing it doesn't matter what kind of stove they have.

As for the 5.5/6 inch thing - I know Ahren's makes an adapter for their liners so that a 5.5 liner has a 6" connection to the appliance and I've seen a few. The bigger question would be - If you're relining the flue have you checked it's current condition? Virtually all liners going into a chimney serving a solid fuel appliance are required to have insulation around them if there is any issue with the terra-cotta liner. That includes cracks and open mortar joints. IF you have to insulate it's highly likely the tiles have to come out and then it doesn't make much difference if it's 5.5 or 6 inch.
As i have said here many times before while i agree almost every liner for a wood stove requires insulation the condition or even existence of clay liners doest determine that. It comes down to clearances to combustibles which are almost never there. And ul listing requirements
 
Why not ovalize. What size tile do you have?
 
So they said they will insulate by pouring mortar down around the liner, so it will be insulated. I don't know why they couldn't do a 5.5" ovalized--I will ask about that!

I know there are adaptors to fit the 6" collars to 5.5" flue, but we need a stove that specifically says it is approved for a 5.5" flue so we meet code and all. So far the only brand I've found that says that their stoves are tested and approved for 5.5" are the Regency inserts...which are good stoves, so maybe in the end we'll be happy that we found the extra money to put one of those in =) Just wish I had more than one stove to compare, and price shop around for, but they see to be the only ones approved for 5.5" flue.
 
So they said they will insulate by pouring mortar down around the liner, so it will be insulated. I don't know why they couldn't do a 5.5" ovalized--I will ask about that!

I know there are adaptors to fit the 6" collars to 5.5" flue, but we need a stove that specifically says it is approved for a 5.5" flue so we meet code and all. So far the only brand I've found that says that their stoves are tested and approved for 5.5" are the Regency inserts...which are good stoves, so maybe in the end we'll be happy that we found the extra money to put one of those in =) Just wish I had more than one stove to compare, and price shop around for, but they see to be the only ones approved for 5.5" flue.
An ovalized 5.5 would be way to small you loose volume when you ovalize. Also using pour in in your case absolutly will not bring it up to code. You need 1" of insulation around the pipe for pour in and you just dont have the room.
 
Joy, what are the interior measurements of the clay liner? There are other solutions that may work well, but we'd just be guessing without knowing what there now.
 
The Hampton HI200 accepts a 5.5" liner. I think it's the same as a Recency.
 
Yes, Hampton and Regency are the same manufacturer.

The size of the terra-cotta liner will help focus the discussion. If you want it installed to zero clearance to combustibles you will be hard pressed to get even a 5.5" liner with insulation down an 8x8 flue tile. You may be able to ovalize a 6" just enough to make 5.5" inch in an 8x13 and reround it once you get it through the throat. Otherwise, the tiles will need to come out......of course as I write this it dawns on me that we're talking about a fireplace...duh....and it certainly shouldn't be an 8x8 flue. Never mind.

Pouring mortar around a stainless steel liner does not constitute insulating it. Nor does pouring loose vermiculite or homemade insulation mixes as far as code and listings go. It needs to be wrapped with ceramic wool (usually 1/2") or have at least 1" of APPROVED insulation on all sides of the liner.to the bottom of the flue. If they are pouring insulation it would seem to be a lot cheaper and easier to wrap the liner instead.
 
So, update: Decided to go with the smaller 5.5 flu (and the more expensive Regency stove approved for that flu) so that we would have the clearance for insulation. So far the stove has been working great (our house is regularly 70 degrees now, it's awesome!). It currently has pieces of batt fiberglass insulation around the pipe, I believe, but they are planning to pour mortar/cement in the Spring when it's warmer.

Thanks, all for the advice, and encouraging us to go with the high-quality stove instead of trying to squeeze a larger flu and used stove =P We're really happy with the performance so far!