Where should my Model 550 Aprilaire humidifier be located?

Consumer question:

Recently I had central air conditioning installed on my hot air furnace. After installing the coil the contractor found that there was no room left to reinstall the Aprilaire 550 whole house humidifier on the supply side. He then installed it on the return side just before the Hepa air filter cartridge. He ran an aluminum circular flexible duct over to the supply side.
I have concerns about this:
1) won’t this simply force water into my hepa filter and create mold /mildew in it?
2) By the contractor running the flexible circular ductwork over to the supply side – is this sufficient to force all the available water moisture coming from the Aprilaire unit into the supply ductwork?
3) Should the unit now be attached to the hot water line instead of the cold water line?
4) Considering the lack of room to install on the supply side [since the a/c coil has been installed] is there any other more preferable place to install this uni
t other than the return side – and risk soaking the Hepa cartridge air filter?

Thank you for your time and consideration on these critically important matters.


Aprilaires’ response:

Thank you for contacting us about your humidifier and addressing these issues with us. I’d be happy to explain what can be done here.

1) It is ok for the humidified air to be introduced ahead of the filter. This is because our humidifier is creating a vapor. Vapor is just like the moisture already in the air. Its invisible, light and cannot condense onto anything such as the filter media or the duct work itself.

2) The beauty of our by-pass humidifier models is that the force will be equal no matter which side the unit is installed on. This is because force from the furnace is the same regardless of any new add-ons.

3) Cold water may be ok. If you have a standard furnace and only run the humidifier when the heat is on than cold water is okay. The only time cold water would be bad would be in situations where you run your fan to try and humidify (no heat source in this application).

4) Referring back to question 1, If the supply side is not available and return side is a equal alternative. Air flow will still allow the air to circulate through the air filter without harm and will continue to create and obtain the adequate humidity you are looking for.

If you have any questions please give us a call @ 1-800-334-6011.

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