New installation, Horizontal vent does not have a screen

  • Active since 1995, is THE place on the internet for free information and advice about wood stoves, pellet stoves and other energy saving equipment.

    We strive to provide opinions, articles, discussions and history related to Hearth Products and in a more general sense, energy issues.

    We promote the EFFICIENT, RESPONSIBLE, CLEAN and SAFE use of all fuels, whether renewable or fossil.


New Member
Aug 11, 2022
Northeast PA
Hello - We just had a Harman P61 Pellet stove installed by our local Harman dealer. The exhaust is an "Out and up" type where it goes through the wall at the bottom, and then goes vertical outside up about 5 feet and then has a 90 degree elbow which terminates horizontally with a cap. I noticed that the cap does not have any kind of metal screen or guard that would keep rodents and other small critters out of the pipe, it's just entirely open.

I called the dealer and they explained that it should be kept entirely open and that you don't want a screen there, otherwise soot will develop on it and eventually clog up the pipe. They did say you can put a cover over it in the warmer months when not using the stove. I just wanted to get feedback from others if this should be left open, or if they have some sort of screen. I know I have seen other installations of pellet stoves where there is a screen on the termination cap.

The dealer used the DuraVent Pro 3" piping. Any feedback is appreciated!
Go with what your dealer said. Screen is not a good idea
I put a plug in mine to keep birds out in the summer
Must remember to remove it in the fall
I would not put a screen on it during the heating season, that sounds like a very bad idea...

My pipe gets a 1/8 inch layer of ash caked all the way around the inside, and the terminal spout gets a bunch of ash caked in it as well.

In the offseason I take the outside pieces down and put a 4" Fernco cap on it to keep critters out.

As everyone else has said - no screen for heating season. Then plug up during the off-season to keep critters out. Until this year I would use crumpled newspaper inside the pipe with a freezer bag over the outside. This year I got a plumbing cap that worked well (and now I don't have to worry about missing any of that crumpled newspaper).