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Heat, AC and Humidifier Hookup
Humidifier
Modifications to the Humidifier
In order to have the humidifier work effectively with the next nest thermostat, we should drive the solenoid only. We will not need the flow check switch or the on furnace mounted humidistat.
Remove wire from furnace mounted thermostat.
Remove the wire to the furnace mount thermistat at the solenoid controller.
Remove the cap to the controller and cut the wires for the flow check switch and marret the connections together. The other 2 wires go to the solenoid valve.
The end result should be resemble the following:<PIC>
Wiring the Humidifier
References
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