Humidifiers and Dehumidifiers - wiring in a Autoflo Su-20 Steam Humidifier

I have a aprialaire bypass humidifier on my furnace that doesn't do a thing to increase humidity. I picked up and installed a autoflo su-20 humidifier. I installed a seperate humidistat to control the su-20. It has a blower motor lockout on the reverse side of the control. Where do I hook these up to the furnace? I see where the existing thermostat is hooked up but The wires are just lablel with letters. The furnace control unit is a General 90. The furnace is a comfortmaker 90 plus. The thermostat I have is a Ritetemp 8082c.

The other reason I installed this is the Aprialaire bypass unit is installed with the ritetemp thermostat/humidistat. If I try to increase the humidity in the house it just runs the blower motor. I let it go for 3 days stright before I gave up on it. It is about 20% RH in the house I believe.

THanks in advance for the help.

Click here for pictures of the furnace and wiring mess! (http://smg.photobucket.com/albums/v491/jasonspector/Furnace/)

I have a aprialaire bypass humidifier on my furnace that doesn't do a thing to increase humidity.
Are you planning on keeping this on or taking it off?


I picked up and installed a autoflo su-20 humidifier. I installed a seperate humidistat to control the su-20. It has a blower motor lockout on the reverse side of the control. Where do I hook these up to the furnace?
Did you get a relay or some type?


I see where the existing thermostat is hooked up but The wires are just lablel with letters.
The t-stat don't hook up to the SU-20.


The other reason I installed this is the Aprialaire bypass unit is installed with the ritetemp thermostat/humidistat. If I try to increase the humidity in the house it just runs the blower motor. I let it go for 3 days stright before I gave up on it. It is about 20% RH in the house I believe.
I see it's not put in "right".. The humidifier is blocked by the A-Coil.

I also don't like the RiteTemp set up for humidifier because it force the fan on. The humidifier needs heat/hot air to work right.

Are you planning on keeping this on or taking it off?



Did you get a relay or some type?


The t-stat don't hook up to the SU-20.


I see it's not put in "right".. The humidifier is blocked by the A-Coil.

I also don't like the RiteTemp set up for humidifier because it force the fan on. The humidifier needs heat/hot air to work right.

I was figuring on leaving the bypass unit in. The interlock on the SU-20 supplies 24v do I need a relay? The a coil is below the su-20 sitting in the plenum about 10" above the bypass unit. I don't see how the A-coil would be in the way. I don't like the RItetmep for humidity, I called them and was told there is no way to set it up to just run with the heat. I really want to get this hooked up so please give me some wiring insite if you can.

I was figuring on leaving the bypass unit in.
Are you going to undo it from the RiteTemp, or what's the game plan?

The interlock on the SU-20 supplies 24v do I need a relay?
Yes, if we wired it to your furnace, we are going to short out both transformer on the furnace, and the humidifier.

You wire SU-20 to the coil side of the relay, and wire R and G from the furnace to the NO side of the relay.

The a coil is below the su-20 sitting in the plenum about 10" above the bypass unit.
When you take the pad out of the Apilaire, what do you see inside of the duct? (Must be a low coil)

Are you going to undo it from the RiteTemp, or what's the game plan?


Yes, if we wired it to your furnace, we are going to short out both transformer on the furnace, and the humidifier.

You wire SU-20 to the coil side of the relay, and wire R and G from the furnace to the NO side of the relay.


When you take the pad out of the Apilaire, what do you see inside of the duct? (Must be a low coil)

I guess I could undo the aprilaire as it does nothing anyways. I will just pick up a piece of tin from the depot. I am not sure what to do about the wiring for the aprilaire though. It has 2 wires going to it that supply 24v. What kind of relay should I pick up? (24v 5 pin relay?) If you take out the aprilaire you can see the top of the A-coil about 5" below that unit. Oh BTW I did that last year. I shorted out the transformer and relay in the SU-20 and the transformer in the furnace. Fun night last winter. I ran to walmart and picked up 5 space heaters.

Any relay with 24 volt coil will work.

I take it you are up and running again after shorting out the transformer last year?

Any relay with 24 volt coil will work.

I take it you are up and running again after shorting out the transformer last year?

Yah the next day I ran to the store and picked up a transformer.

Electrical > Relays > Relays > Relay,SPDT,5 Pins,24VAC : Grainger Industrial Supply (http://www.grainger.com/Grainger/items/4A708)

Will that work?

http://www.autoflohumidifiers.com/pdf-files/SU14-SU20-Instl-Instr.pdf

I am confused by what you told me and this? :wall::wall:

http://img.photobucket.com/albums/v491/jasonspector/wiringdiagram.jpg?t=1230049854

http://img.photobucket.com/albums/v491/jasonspector/wiringdiagram.jpg?t=1230049854

Wire it as shown in Fig. 7A.

The to furnace is wired to R and G.

Yes, that relay will work that you posted from grainger.