How will humidifier plenum hole downsize be done?

[MikeV99]

The wrong humidifier was installed on my system (heat pump & A/C). I have a horizontal furnace and a fan powered unit was installed. This was discovered thanks to the help on this forum. What should have been installed was bypass unit.

The fan unit has a 14.813" x 15.25" opening. The bypass unit has a 9.875" x 12.75" opening. Obviously, the hole in the plenum will need to be reduced to fit the bypass unit.

How should the HVAC technician reduce the size of the hole in plenum, which is a sheet metal box, and install the bypass unit? Will they be able to do it so that it does not leak? I am hoping that the entire supply plenum will not need to be replaced? What should I look for in the finished installation?

Thanks

Mike

[d_griff]

It shouldn't be that difficult. The tech can put a piece of panning across the old hole, And then cut the new hole into that

[MikeV99]

It shouldn't be that difficult. The tech can put a piece of panning across the old hole, And then cut the new hole into that

I am a little gun shy on the techs from this vendor. Had I not bought the unit from him initially I would probably use someone else.

Would the patch just be installed with some sheet metal screws? How would it be sealed around the edges?

I have found what appears to the the solution to my problem. I am seriously considering the Honeywell HM512VPIAQ as the replacement rather than the bypass unit. It requires an even smaller hole (1-3/4") and hopefully it will make it easier to patch. I just hope the vendor is up to the task.

Thanks for the response.

Mike

[troyorr]

Sounds like Mike cut the wrong size hole.

[MikeV99]

Sounds like Mike cut the wrong size hole.

Actually a vendor installed a Carrier fan-powered humidifier on a horizontal plenum. Unfortunately, he did so without checking the specs closely enough to find out that it should not be installed. Hence, I have had blow back air coming out of the unit for the last 2 years. A post on this forum pointed out the problem.

Now I am trying to figure out the best solution for replacement.

Arggg...


Mike

[MichaelPaladin]

I am a little gun shy on the techs from this vendor. Had I not bought the unit from him initially I would probably use someone else.

Would the patch just be installed with some sheet metal screws? How would it be sealed around the edges?

I have found what appears to the the solution to my problem. I am seriously considering the Honeywell HM512VPIAQ as the replacement rather than the bypass unit. It requires an even smaller hole (1-3/4") and hopefully it will make it easier to patch. I just hope the vendor is up to the task.

Thanks for the response.

Mike

Yes sheet metal (Zip) screws and some mastic and top off with some metal tape. I know some parts house carry flat metal, heck even Lowes carries small sheets that normally made for panning between joists still works good for a patch.

[beenthere]

I'd hope he uses heavier guage stock then panning.

But, yes a piece of flat sheet meatal can be used.

You would probably be better off with a steamer instead of just a bypass.

[MikeV99]

Yes sheet metal (Zip) screws and some mastic and top off with some metal tape. I know some parts house carry flat metal, heck even Lowes carries small sheets that normally made for panning between joists still works good for a patch.

I'd hope he uses heavier guage stock then panning. But, yes a piece of flat sheet meatal can be used. You would probably be better off with a steamer instead of just a bypass.

Mastic and metal tape. That should do the job! Thanks all, it was exactly what I needed to know.

I am leaning toward the Honeywell HM512VPIAQ steam unit. It looks like it will just perfect for my situation.

Thanks

Mike