We have purchased a Warm Morning vented heater as our primary source of heat. The plan was to vent it into an existing chimney which had previously had a wood stove hooked to it.

First someone said that once you vent a gas appliance to a chimney like that you can never use it as a chimney for a woodburner. Something about a chemical reaction causes excess cresote formation. Is this true?

We called a heating/cooling man to try and figure out if we could do it ourselves or need to pay someone. He said that if the chimney "opening" is too big that the vented fumes could swirl around in the chimney, freeze, and you could end up with the opening only being the size of a pencil.....

So, IF this is true, (the heater "outlet" is 5" and the chimney is 8") we were thinking that we could install the vent pipe inside the chimney. That would a) mean that the chimney could be used with a wood burner in the future, and b) eliminate the possible frozen gas problem.

Comments??

-- Joyce Dingman (FriendsPatterns@juno.com), September 21, 2001

Answers

havnt heard of that,, and the only vent Ive sen go thru an existing chimney that was still being used,, the vent acually ran THRU the chimney, all the way to the top. Keep in mind,, it was a large chimney to start with,, and the vent was only 2 or 3 inch

-- stan (sopal@net-port.com), September 21, 2001.

I have a 12 inch flu and I had surgery one year so I couldn't cut wood. I put in a LP gas worm morning stove for that winter. I am now back on wood and have not had any problems with the gas or wood burner. I think that was 8 years ago I used gas. Hope this helps.

-- Mel Kelly (melkelly@webtv.net), September 21, 2001.

i believe the problem you're referring to Joyce is that propane exhaust will react with the mortar joints in your chimney over time and ruin them. Another problem you may find, if you have a heater with a 4 inch exhaust and put it into a larger flue it will not draw properly. Also you should use b-vent pipe if it is called for in the owners manual. Just last week I had a customer who was cursing his heater because it kept going out. He had installed it himself and in order to save money he used single wall pipe. That pipe didn't hold the heat like b-vent does and so the exhaust spilled down the flue entering the house. This fortunately shut down the stove with the safety switch. As soon as it was vented with the right material it worked fine. You can avoid ruining the mortar in your chimney by venting through a liner which would run up and out of your chimney. Read the owners manual carefully. good luck and be safe jz

-- jz (oz49us@yahoo.com), September 21, 2001.

jz: Read in the manual to use b-vent, which I assume is the double wall pipe. Would it be possible to run the b-vent inside the existing brick chimney? Stabalize it at the top with strapping. Then it could be removed if the stove were removed.

I am just thinking that a liner would also make the chimney have a smaller diameter should we (or someone else) ever decide to go back to wood or coal. Would that be permanent or removeable? (permanent I'd assume...)

We'd love to hire someone to do it but have been given a quote of $55 and hour and no estimate of how long it would take. Since we've just been done over by a plumber to the tune of $900 (double the estimate, but that's another story) we are gun shy.

-- Joyce Dingman (FriendsPatterns@juno.com), September 21, 2001.

Sorry Joyce, I guess I wasn't too clear on what I was referring to as a liner. Yes, b vent would work great inside the chimney. We usually cover the top of the masonry chimney with a galvanized sheet metal plate with a hole in it the size of the b vent and a small lip sticking up around the vent pipe ( to shed the rain).Either silicone that plate to thetop of the chimney or fasten it with some masonry anchors and screws. Above that, a rain collar and a cap to keep rain and snow from inside the pipe itself. Support the bottom of the b vent as well, taking into account how long the run of pipe is. B vent locks together with a simple twist but I like to wrap each joint with a turn of metallic tape. This will prevent them from accidentally loosening. I would advise thoroughly cleaning the flue of any creosote before you do anything. I have found a few installations where the flue was not completely sealed off from the house and the chimney was not cleaned resulting in the house reeking of creosote. Stay warm jz

-- jz (oz49us@yahoo.com), September 22, 2001.

jz: Thanks for the tip on securing it at the top of the chimney! We had just been thinking about something like water heater strapping and then the rain cap, but your idea sounds much better. Yes cleaning the chimney is planned for before the installation, and your description will help remind us that it is not an option :-) Thanks again for the good tip.

-- Joyce Dingman (FriendsPatterns@juno.com), September 22, 2001.