Bypass in Efel Harmony

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New Member
Mar 14, 2023

I have a question regarding my Efel Harmony stove.

A few weeks ago we've gotten this stove from some people that were replacing it with a more modern wood stove.

While we've been using it happily, and it's heating up our room quite nicely, I do have one concern.

Along with the stove we've gotten a tool that I think I'm supposed to use but can't figure out how to. In a manual I found on this forum it says that this tool should be used to open a 'bypass'. If I'm reading the (very dated) manual correctly this should redirect heat through the stove. This seems like something I'd want to do, because right now it seems like flames (and thus heat, I assume) are at times sucked into our chimney. This means heat is wasted because it's disappearing through our smoke channel! At least, I think it is.

Anyway, my question;

Does anyone have any idea whether:

1. I should be using this tool?
2. If so, how?! I can't find anywhere in the stove where I can use it to, as the manual seems to suggest, open up some sort of bypass.

Attached you'll find a picture of the tool, a page from the manual that shows how to use it and the entire manual. Screenshot_20230314_092541_Samsung Notes.jpg 20230314_092652.jpg


  • EFEL 386-75 Manual.pdf
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Minister of Fire
Nov 17, 2019
Long Island NY
While I am not sure how to operate it, if the flamed now go up the chimney, the bypass is already open. You want to close it so the gases don't bypass the path where they can shed the heat into your room.


Minister of Fire
Jul 11, 2008
Northern NH
Having never been near one, it sure looks like you could use a crescent wrench to turn the bypass baffle. If the prior owner was not using, its likely that is jammed in the open position and the catalyst would be plugged solid. The catalyst is going to add resistance to gas flow so unless you can force it to go through the catalyst and reburn the smoke its going to find an easier way to go around it.

My guess it you are going to need to take the stove apart and give it good cleaning to get everything moving again.
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Minister of Fire
Nov 23, 2005
how about a picture of the front of the stove