I want to install a whole humidifier

[lzicc]

I have limited space in my furnace room to install a whole house humidifier. If you look at the picture, the duct on the left is the cold air return and the supply plenum is on the right. If I install a bypass humidifier, I need to install the unit on the cold air return, but will have trouble installing the 6" duct bypass to the supply plenum of the furnace. Can the bypass duct be installed anywhere on the supply duct? I was going to install a non bypass humidifier so I didn't have to worry about the bypass duct, but I think they have to be installed on the supply side, which there is not enough room.

 

[frugalangler]

I use an AprilAire on my HVAC, looks kinda similar, so I'll go down and shoot a couple shots of it and re-post for you. IIRC, though, mine is ducted from output riser (updraft system) to cold return before the filter which basically forces some warm air back thru the humidifier into the cold air supply, it's a loop but not a lot of volume, and works well.

 

[orezok]

Double post

 

[orezok]

I live in the Mojave, so added humidity is a winter requirement. Ive been using a Skuttle spray humidifier for 13 years without fail. I have to annually remove the spray head and remove the calcium buildup, but that is the only maintenece and NO cost. Takes about 10 minutes.

The unit is very small and only requires one 3/4 hole in the supply duct.

Spray Humidifier | Skuttle

 

[lzicc]

I like that idea. It needs to be installed where there is at least 6' of straight, non obstructive space, so it seems like it could be installed in the main supply duct which would be good for me. It just more or less sprays a mist of water into the duct. It says that it is made for low temperature heating system. Mine is a gas, force air furnace which I would think would be high heat?

I live in the Mojave, so added humidity is a winter requirement. Ive been using a Skuttle spray humidifier for 13 years without fail. I have to annually remove the spray head and remove the calcium buildup, but that is the only maintenece and NO cost. Takes about 10 minutes.

The unit is very small and only requires one 3/4 hole in the supply duct.

Spray Humidifier | Skuttle

 

[coldsteelva]

I have an Aprilaire 400 or 600. The water plate housing (square) mounts in the cold air return and includes a humidistat ahead of the water plate and prior to the filter and the warm air duct (round) (that I think you are calling a bypass) is ducted to the warm air supply. That duct has a butterfly with summer and winter positions.

During the humidifying season, warm air is drawn by the fan across the water plate picking up moisture, then through the filter and into the supply ducts. During the summer, I pull the water plate, turn off the water, and close the butterfly essentially closing that air loop.

 

[lzicc]

coldsteelva, you are correct, that is a bypass one. I'm wondering if the bypass duct can be ducted into the main supply line instead of the plenum.

 

[coldsteelva]

I'm sure it probably CAN, so long as the distance in ducting is less than some pre-determined 'draw' distance. Without enough airflow across the water plate, the water won't evaporate. I'm sure that info is in the manual; I'll try to find mine.

 

[Cord]

A bypass might be your best option. The supply connection can go anywhere on the supply side, but try to install it well before trunk T. If you get it too close to the T or after the T, you could run into moisture distribution issues where a portion of the house isn't seeing the moisture. Make sure you tap into soft water and I'd suggest using hot water. There are direct injection systems (steam or spray), but they seem to demand a higher level of maintenance.

 

[orezok]

I like that idea. It needs to be installed where there is at least 6' of straight, non obstructive space, so it seems like it could be installed in the main supply duct which would be good for me. It just more or less sprays a mist of water into the duct. It says that it is made for low temperature heating system. Mine is a gas, force air furnace which I would think would be high heat?

My system is propane forced air so I would say that it probably meets their low temp heating system requirement. Mine is installed in the A/C plenum just downstream of the evaporator coils.