Can I Use 6" Flue on EFM 520?

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Post Thu. Jan. 31, 2013 8:10 pm

I'm thinking of buying a df 520, which recommends an 8" flue. I have 6" round steel flue pipe. Can it be done?

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Stoker Coal Boiler: EFM 520, 700, Van Wert 800 GJ 61,53
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Post Thu. Jan. 31, 2013 9:34 pm

Yes it can be done. I used 6" for several years until I got the chimney built. It doesn't work good if you are going to use it on higher settings. I used mine on 4 and 5 teeth feed with the same air and didn't have issues until I jacked it up to 6 and above air. You can also get a little help with a draft inducer like several other members are successfully running.

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Hand Fed Coal Boiler: 1981 efm wcb-24 in use 365 days a year
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Post Fri. Feb. 01, 2013 5:28 am

I know it's done. But if you run into a fire code inspector, he will only allow 7" (or larger). It pertains to the BTUH output of your unit, not how well it works in your personal setup.

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Post Fri. Feb. 01, 2013 8:05 am

Thanks for your input - much appreciated!

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