Question about Aprilaire 550 Humidifier

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No water to my Aprilair model 550.

It has an auto-humidistat that works off outside Temp. and is located on the cold air return. Two things are run off the 24 volt transformer, the humidifier water feed solinoid and the humidifier drain sump pump. When the blower comes on the drain sump pump gets 24 volts but the water feed solinoid does not. I do have water to the solinoid valve but it doesn't open.

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Re: No water to my Aprilair model 550.

Some sump pump have a safty switch that will not let the hum. come on if the tank is full of water, I,m not sure if this is the type that you have but make sure that the pump is pumping water. Also your humidistat have an internal switch that it should be set to bypass not to power Note: some humidifier have their own power supply the 550 dose not

Posted on Feb 09, 2009

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