Flue question

Hi everyone

I have been dreaming of building a rocket stove to heat my extremely cold, extremely damp flat for a while now. I been reading with interest many of your posts. as well as watching tons of video on how to build it. I can't find the information I need regarding using an existing chimney. And this may seem like (and probably is!!!) a completely obvious question to all you knowledgable folks. But what type of pot do I need on an existing brick chimney in order to install a rocket stove like this? http://www.iwilltry.org/b/build-a-rocket-stove-for-home-heating/

The pot fitted on my chimney is for a gas fire, but as I have read that the stove only produces steam and CO2, not smoke I wondered if it might be OK. I can't get the pot changed as it would require scaffolding and cost way too much. I am on the ground floor of a three story building. Any help or advice would me most appreciated. Thanks

I am a rocket mass newb myself but I do know a thing or two about building (although more from a commercial stand point than residential).

I am not sure if your chimney was built as a regular fireplace with gas added later or if it was originally build for a gas fireplace. Keep in mind, that the flues for gas appliances are usually designed for much lower temps than a regular stove or chimney. It may come down to temperature much more than which kind of gas is being exhausted. Also, gas appliance flues are also usually fairly small, so it may not be large enough for a rocket heater. You may not care what local building codes say, but it is something to keep in mind.

Make sure you know how your house was put together and what exhaust temp will be safe. I am sure others here can cover how much mass you need to run through to get a temp where you need it if you decide to proceed. I just recommend using extreme caution for something designed for gas appliances.

Hi CR

Thanks very much for your reply, which has filled me with hope!!! The chimney is in an old Victorian building. It was used as an open fire for many years. Until the landlord hired a company to line the flues of the house next door with gas liners. The chimney was demolished and rebuilt and by mistake my pot was changed from a normal chimney pot to a gas pot. I complained but the builder had had an argument with the landlord and walked off site. So I was left with no heating. This was a couple of years ago. I have asked and asked for the pot to be changed but to no avail. The heating is electric, inefficient and costs a fortune. To add insult to injury the property is in the middle of a small woodland so there is a plentiful supply of wood.

When I learned about the emissions a Rocket Stove gave off - I dared to hope!!! The chimney is approx 60ft in length and I will be having it smoke bomb tested before proceeding to ensure that the flue is intact. I was thinking of making one of the small stoves from a gas bottle. And fixing it like the guy in the link has. Also fitting a Carbon Monoxide detector.

Any advice on how to proceed/safety checks would be gratefully received. Thanks again.