Humidifiers and Dehumidifiers - Controlling Flow Through Humidifier

Hello, I hope you can help me.

I have installed a flow through humidifier (Wait 5000 model by Air King :: Air King Limited (http://www.airkinglimited.com)) to my electrical Goodman furnace (air handler) a couple years ago. I never got it to work as designed.

It supposedly should start when 2 conditions are met: humidistat is on AND flow detector is on. When the flow detector is sensing a given gain in temperature in the bypass conduct, it should energize the solenoid water valve...

I have installed everything according to installation manual. In that manual, it was mentionned that it was possible that the flow detector would not work if the air flow was not calibrated properly... So I presume that it is where my problem lies...

Since installation time, I have bypassed the valve and controlled the flow manually, wasting megaliters of water...

So here is my question: is that possible to control the solenoid valve with both a humidistat AND a thermostat? For a while, I was naive and thought I could procede a little bit like a light fixture that is controlled by 2 switches but it does not seem it is that simple... It turned out that my humidistat controlled BOTH my furnace and my humidifier...

Update: I just got a call back from Air King technical support telling me that I needed a pressure switch that they sell for 25$. Is there another way to work this out?

I thank you for your help!

my electrical Goodman furnace (air handler)
What is the model # of the air handler?

We may be able to wire to the unit, but most of them don't allow it. But we will find out when you post the info.


Update: I just got a call back from Air King technical support telling me that I needed a pressure switch that they sell for 25$. Is there another way to work this out?

That will work, or the A50 relay can be used if we are not able to wire it to the air handler.

I am impressed by your readyness and I thank you, Mr Jay.

The model is ARUF036.

Would you please briefly explain why is the analogy I made with the light fixture not valid?

Thank you again.

Ok, the air handler has no hook up on it to work.

I am not really following on the "light fixture", do you mean switch instead of fixture?

I thought that I could wire the thermostat and the humidistat together in series (could I say) with the solenoid valve to control it in the same fashion that a light fixture can be controlled by 2 switches...

I would like to have an explanation on how this analogy fails...

Thank you very much for your time.

we could wire it to work with the t-stat, but is your system a heat pump with electric back up heat?

What is the make and model of t-stat is running this set up?

The thermostat is Aube Technologies (Honeywell) model th141a-hc-28.

After thinking about what the technical support person told me about the pressure switch, I come to wonder if it would be possible to wire the thermostat to the humidifier's control box, particularly those 2 terminals used for the pressure switch.

That is where I am heading right now...

Thank you again

...is your system a heat pump with electric back up heat?

Sorry! I missed a question: >> No heat pump is involved...

Thank you !

So, the idea of connecting a pair of wires from the thermostat to the pair of terminals on the humidifier control box that are supposed to be used for a pressure switch was good.

I observed the thermostat's behavior with a multimeter... I took Rc and G, that I found out are used to control the fan when in cooling mode and for some particular furnaces(1) that need to be told when to blow in heating mode, and connected them to the humidifier control box.

It works perfectly. The only thing is that if I leave it like that over summer, when my wife starts the central air fan, it is going to pour water down the humidifier...

I hope that that solution can help someone... If my explanations seems short or confusing, I am willing to clarify them...

Thank you Mr Jay

(1) In order for that solution to work, I had to switch on jumper #6 on the thermostat board. That way, G gets energized when the heater starts... Cool! Is not it?

What I was going to suggest, is hook one wire on the W, that powers up when the t-stat calls for heat. That way you don't have to worry about it in the summer months when the fan is on.

Then common side of the system goes to C.

So would be hooked up like this below.. The "HUM" on the drawing will be your "W" t-stat wire hook up. do you have more than one W's on the air handler?


http://img528.imageshack.us/img528/844/24humnorelayyf2.jpg

What was switch 6 set to before?

C:\Documents and Settings\Éric\Desktop\table.jpg

If you are trying to post a photo, you need to upload the photo to a photo host site like imageshack.us, or yahoo.

Hello Mr Jay,

I had a hard time with the pictures... And still, all I can do for now is add a link...

So this first link Table (http://picasaweb.google.ca/lh/photo/tU4Q5bIvWVvECN2-24Gvpw) shows what wires connect under which condition.

This second link Schema (http://picasaweb.google.ca/lh/photo/1dcnYc5sLo4bWcJ7K8Lw5g) shows how I got it to work.

I do not see how it would work differently. I do not understand what to do with the "common side"... If you look at the table, there are no common wire on the thermostat...

As for switch #6, it was off...

Thank you again.

Undo the humidifier wire now!

I am doing some more reading on the humidifer now...

I did not see a drawing for the humidist... Is your unit a build in type? (digital on top?)

Ok, more questions.

-YOu ran a wire all the way up to the t-stat for the humidifer?

-There is no G hook up at the t-stat to the air handler?

-Is there a jumper between Rh and Rc?

Undo the humidifier wire now!

I am doing some more reading on the humidifer now...

You seem worried, Mr Jay. Be assured, everything is working fine. No overheating. No problem.

I am about to answer other questions...

Thank you again.

I did not see a drawing for the humidist... Is your unit a build in type? (digital on top?)

The power (24VAC - 750mA) is coming from a plug-in transformer. The wire coming from that transformer is interrupted by the humidistat and is connected to a pair of terminals on the control box labeled "24 VAC IN" . That control box has 3 pairs of connectors in all: one for the power (controlled by the humidistat), another ("24 VAC OUT") that is used to connect the solenoid water valve and the last one that is designed to connect a pressure valve.

It is that last pair of terminals that I drew and used to plug the wires from the thermostat.

-YOu ran a wire all the way up to the t-stat for the humidifer?

No. I used the wires in place...

-There is no G hook up at the t-stat to the air handler?

You are right. There was one but I used it to solve my problem and plan on putting it back when I do not need the humidifier anymore in spring time...

Unless there is another way to solve that problem... And I think you have one to suggest... but do not understand that "common side of the system" story...

-Is there a jumper between Rh and Rc?

There was one but I removed it in order to achieve the values in the table for which I provided a link in a previous post... >>> (http://forum.doityourself.com/humidifiers-dehumidifiers/369678-controlling-flow-through-humidifier.html#post1474581)

Thank you again!

Ok, you are lucky!

if you had a jumper there now, you will short out both transformers, so that's why I freaked out! Also, you are feeding back some voltage to your A/C, and not good for it in the long run

And you are going to be asking for trouble down the road if your wife turns on the A/C and you did not make the "switch".

Undo what you've done, and do this.

You won't need the plug in transformer that came with the humidifier.

There is a "C" on your furnace.. From your drawing it's the Blue wire (BL), same wire as the A/C is returning to the air handler.

Hook it to W and C (BL), and you will be fine, and no worries.

Be sure to put the switch 6 back to where it was before.

Another thing I notice is your BR (Brown) wire, is that hooked up to anything? How many KW is your heater?

Another thing I notice is your BR (Brown) wire, is that hooked up to anything? How many KW is your heater?

I think it is a 15kW. If I remember correctly, I installed 3 sets of elements in it when I purchased it.

What is the brown wire used for?

I am going to draw what you suggest I do just to make sure I do not do anything stupid and will submit it...

Thank you.

I think it is a 15kW. If I remember correctly, I installed 3 sets of elements in it when I purchased it.

What is the brown wire used for?

The brown wire is use to stage the heating elements.

Are all 3 tied to W/hite now?

Ideal set up is 1 elements tied to W1 (1st Stage), then 2 elements tied to W2 (2nd Stage). But you will have to up grade the t-stat since it's a single stage.

When you stage the heating system, you get better comfort with longer run time on a lower heat out put, than all at once.

You must get an awful good rate to heat your home all electric?

Are all 3 tied to W/hite now?


I understand. My setup is single stage for the time being so I presume that all 3 elements are connected to W...

You must get an awful good rate to heat your home all electric

Rates are cheaper here in Québec and my house is not very large...

A couple of years ago, we were heating with an oil furnace. We had to replace the oil tank so I decided to throw the tank out the door and the chimney out the windows (literally - brick by brick) and go electric...

Thank you Mr Jay

You won't need the plug in transformer that came with the humidifier.

There is a "C" on your furnace.. From your drawing it's the Blue wire (BL), same wire as the A/C is returning to the air handler.

Hook it to W and C (BL), and you will be fine, and no worries.

Where is the power to activate the solenoid water valve going to come from?

Thank you.

Where is the power to activate the solenoid water valve going to come from?

It is getting power from "W" when t-stat calls for heat, that powers up, and sends power to the humidifier.

That way, we don't have to worry about it coming on when the A/C gets turned on.

It is getting power from "W" when t-stat calls for heat, that powers up, and sends power to the humidifier.

That way, we don't have to worry about it coming on when the A/C gets turned on.

Very good! Drawing in progress...

Thank you !

Hello Mr Jay,

Here is a more recent schema (http://picasaweb.google.ca/lh/photo/sf_uJOX66a-hzqkaRqwcFg) that I plan on applying shortly...

Do you think I got it right?

Thank you

You got it! Wire it up, and you are good to go.

Hello Mr Jay,

I am going to do that tomorrow...

If I need more help, I know whom I am going to turn to...

Until then, I thank you for everything.

So long, Mr Jay.

Glad to help, and I will be here on and off tomorrow while I am baking cookies. :coffee: