Lennox WP18 Humidifier w/ Pro1 IAQ Humidistat

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species8472jj
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Lennox WP18 Humidifier w/ Pro1 IAQ Humidistat

Post by species8472jj » Thu Dec 27, 2012 2:54 pm

Furnace - Lennox 2 speed G60
Humidifier - Lennox Healthy Climate WS18
Thermostat/Humidistat - PRO1 IAG T955 WH

I just had the humidifier installed, and the installer also put in a manual humidistat. The humidifier will only activate if there is a call for heat.

My goal is to wire the humidifer to my Thermostat/Humidistat such that when there is a call for humidity, it will activate the furnace blower and activate the humidifier.

So I bought a 24 VAC relay and wired the H and C terminals (of the thermostat) to the "coil" side of the relay. The other 2 terminal of the relay got wired to the humidifier.

When I did this, the furnace blower would turn on when there is a call for humidity, however humidifer fan would not activate.

I had a Honeywell Truesteam humidifer and used the same wiring configuation and it worked fine. I am just not sure why this will not work correctly. I can say that the relay I'm using is brand new and I checked the voltage going into the relay and there is 28 volts going into the relay (according to my volt meter).

Any suggestions would be appreciated.

Freon
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- Lennox WP18 Humidifier * Pro1 IAQ Humidistat

Post by Freon » Fri Dec 28, 2012 3:29 pm

Is this a simple SPST relay

You say The other 2 terminal of the relay got wired to the humidifier. To what terminals in the humidifier did you wire the relay? Is this a simple 120 volt powering of the humidifier using the relay.

species8472jj
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- Lennox WP18 Humidifier * Pro1 IAQ Humidistat

Post by species8472jj » Fri Dec 28, 2012 3:55 pm

Thanks for the reply.

Yes, it is a simple SPST Normally open 24 VAC relay.

The H and C side are attached to the "coil" side. And the two wires from the humidifier are connected to the "normally open" contacts.

I hope this clarifies.

Freon
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- Lennox WP18 Humidifier * Pro1 IAQ Humidistat

Post by Freon » Sat Dec 29, 2012 1:51 pm

Turn off the power to the furnace. If you take the 2 wires from the humidifier that connect to the relay and twist them together making a connection and then turn on the furnace, does the humidifier run. What is the voltage on these 2 wires going to the humidifier 24 volts or 120 volts.

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