Question about Honeywell HE120A Whole House Humidifier

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Why dose drum spin when furnace is not on?

Just installed honeywell he120 last night unit is mounted on supply plenum and bypass runs to return. the humidistat is about 15inchs from the bypass collar on the return duct. So i turned it on to high like directions say and the drums spins corretly but when the furnace shuts down the drum is still consintly spinning. then when i turn it to low or med the drum does not spin but i can here the humidistat click when i turn it to high. just wondering if this is susposed to be constanly spinning. it not wired to heater but to seperate 24v trans. should i wire it to my heater 24v if it has one?

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Usually the unit is mounted to the cold air return (cold or intake air) and the round hose is then attached to the plenum (hot or discharge air). The humidistat is usually mounted just above the unit onto the meta plenum, unless you have a control somewhere else or your main t/stat has that capability built in. Its usually wired in with the furnace 24Vac control (or whatever yours happens to be) so that the unit only comes only when the furnace is on.

Posted on Jan 31, 2015


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