Quote:
Originally Posted by dad911
Is the Furnace chimney still in use? Have you updated to high efficiency furnace or HW heater? Alot of people don't realize that newer furnaces/HW don't heat masonry fireplaces enough to get a good draw, and need to run a stainless liner for the furnace/HW heater.
|
Here we are not allowed to mix fuel sources in one flue. Gas furnace and water heater can use the same flue but not a gas water heater in a chimney with an oil furnace (unlikely anyway) or a wood stove with a oil furnace etc When you remove the gas furnace and go direct vent the remaining gas water heater needs a smaller chimney and then you pull in a liner.
When you have two flues side by side the morter might have crumbled allowing gases from one flue into the other even though the tiles are intact.
I have installed a stainless liner kit for a high efficiency(airtight) insert.
We used a piece of "Roxul " batt insulation as a stuffing around the liner at the top and bottom but didn,t bother in between. Roxul is mineral or stone wool I think so is fireproof. I think You would need to fabricate a sheet metal lid for your firebox to terminate the bottom at the fireplace if not using a factory made insert.