Steam Humidifier Aprilaire 800 Hot Water Supply


Old 10-08-19, 08:24 PM
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Steam Humidifier Aprilaire 800 Hot Water Supply

Looking for some feedback. In the instructions on the Steam Humidifier Aprilaire 800 it says to install with a cold water supply, however my installer hooked it up with the hot water as he insisted this is better because it would use less energy than the device alone to heat up cold water.

I get that it is heated one way or another so that is somewhat irrelevant. However having the device hooked up with hot water; will this cause any damage to the humidifier itself over time? Or any other concerns?
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Old 10-09-19, 04:27 AM
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There are a couple of reasons why this is not a good idea.
The first is that you do not know if the fill valve solenoid is rated for hot water.
I checked the manual and there is no mention of this.

The second is that during your humidifier's steam cycle the unit regularly flushes the steam canister when the conductivity gets too high and also on a timed cycle.
There is a requirement that the humidifier not discharge boiling water to the drain and cold water is required to cool the drained water.
If you have ABS drains they could deteriorate as this material is not rated for boiling water......copper and PVC are.
It could also make the drain line excessively hot and possibly burn someone.

There could be occasions when connecting a humidifier to hot water may be an advantage but unless you can seriously weigh ALL the consequences it's better to not do so.

You have a fairly high tech humidifier so make sure you follow maintenance instructions, especially repalcing electrodes when they suggest you do.
pharesf voted this post useful.
Old 10-09-19, 12:57 PM
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From Aprilaires installation instructions......

Plumb the humidifier to cold, hard or softened water.
Do not use hot water because unheated supply water is used to cool water draining from the humidifier.

Therefore it should be reconnected to a cold water line.... regardless of cost savings.
The drain line is in danger of melting with hot incoming water.
Old 10-20-19, 12:51 PM
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The drain pipes in our condo highrise are all metal once they leave the suite and this humidifier drain is connected to the metal portion of the drains
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