Covering cold and warm vents on Heatform fireplace

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Thanks to all who contribute to this site. A fantastic source of info. I have done a bunch of reading on Heatform's and VC Montpelier Inserts.

I am pretty confident I have a Heatform firebox (Steel sides/back/top - Brick bottom - 3 steel pipes thru top of box -- Intake vent lower left/right -- Heat output vent top middle -- Masonry face- Concrete Block chimney lined with flue tile). It looks like it is good condition---- no rust, etc. I am planning on getting a cert. chimney sweep to check everything out.

I am considering installing a VC Montpelier and replacing the 70's era brick face on the hearth. I will have a pro install but want to really understand what is going on and make sure its done right.

I think its safe to cut/remove the middle tube to run the SS liner. Does that sound correct?

Does anything need to be done to the cutoff end of the pipe prior to installing the SS liner ?

The installer said he would use rockwool and simply stuff it around the SS liner as opposed to installing a blockoff plate. This sounds wrong. Should I have him install the block off plate ?

I plan on covering over the old brick face with duroc sheeting and then setting the stone veneer. Can I completely & safely cover over and block the cold and warm vents for the old heatform ?


Thanks for your help.
Kelly

 

[basod]

My setup was similar heatilator steel preform with lower and upper vents. My style of preform had a triangular shapped heat exchange duct running from front to back. It was a royal pain to cut out but multiple cinders down the forearm and large hammer did the job. Its probably impossible to cover the holes left by the tubes being cut out. I used a seesnake tool to look into the voids and ensure it was all block and mortar and no wood was used internally to brace during construction. The liner with insulation should cover you as far as exposure to any combustibles in the voids but being a pro is doing the install I ensure he/she is checking that out anyways. I solid block off plate of sheetmetal would be advisable as the fiberrock insulation has silica dust and sealing it off will prevent a blower from potentailly stirring into the room. I amde mine out of a scrap piece of airhandling sheet metal and the sides were insulated and covered with old metal shelfs. It takes extra time but as anyone on here will recommend a block off plate with insulation above it is a good idea. Have it done right once and prevent being disatisfied with your new install.

 

[begreen]

Welcome Kelly. I'm not an installer nor a WETT certified sweep, so this is just an opinion. Our neighbors have this setup with an Avalon Rainier insert. The installer hacked out two of the heat tubes for their installation, but when the stove is running, there is still some heat emitted via the heatform vents.For this reason I would go ahead and put in the insulated block off plate below the tubes. Then I would think your plan is ok. I would add a permanent plaque at the back of the fireplace cavity indicating that the fireplace has been permanently modified and can only be used with a correctly installed insert.

PS: lots of installers balk at putting in a proper block off plate. Not sure if this is due to inexperience or previous bad problems. Might be that some are just not adept at working with sheetmetal.

 

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Thanks for the responses.

I just downloaded and read the installation manual. http://literature.mhsc.com/vermont_castings/manuals/30004403_Montpelier.pdf

Found this info on page 4 for existing fireplace installation
heat-circulating masonry-type fireplace must conform to building code standards for masonry fireplaces, and must consist of a factory-built metal firebox with air circulation pathways that are surrounded by masonry materials. Air circulation pathways must not be blocked by the insert or surround panels.

Specifically for Canada page 5 "Existing air-circulation chambers in a fireplace with a steel liner may not be blocked."

I will check with a local sweep or inspector for local codes.

I am still interested in the experiences of others who have done similar installations.

Thanks
kelly