Aprilaire 700 wiring


Old 01-11-15, 12:56 PM
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Aprilaire 700 wiring

Hey guys, so I have this unit (Aprilaire 700 automatic) installed on my old furnace and everything works great.

My issue is, the humidifier only goes on when the unit calls for heat. I know I'm missing a wire on the Gf terminal in the humidistat but lost as to where its supposed to go to. Also, the white thermostat wire I hooked up to the W on the humidistat and put it where the white wire on the furnace board went labeled H, not sure if that's correct. The thicker gauge wire is for the sensor and the transformer.

Here are some pictures.

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Old 01-11-15, 05:33 PM
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I don't recommend setting up the humidifier to allow the humidistat to activate the blower. Non heated air doesn't carry enough moisture to make it cost effective for that humidifier. The diagram below is how I wire my installations.

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