Aprilaire 600 not getting any water

Hi everyone,

As winter is here I turned on my humidifier the other day (don't know the terminology but this is a unit without a fan). However, there is no water reaching the water panel. I then checked the humidistat and it is getting ~24V when the furnace is running and there is ~24 volt going to the solenoid valve when the humidistat was set to a higher humidity. However, there was no audible "click" in the solenoid, only from the humidistat. There was also good water flow upstream of the solenoid. I thought this would be an easy fix based on previous posts and ordered another solenoid valve. However, I installed it today and there is no change...no water flowing and no audible noise from the valve when it should be engaged.

So what could be the problem; I installed a new cooling coil on the unit this summer and I initially thought that they perhaps did not "plug everything in" the way it was...but since the humidistat is getting power, that should not be the case..correct?? Could it be that I received a faulty valve. This was a OEM Gems Sensors A2012-S150 replacing a a2012-S118. According to the manufacturer these are compatible.

Thanks!

 

You have the wiring connected to the solenoid and you measure 24vac at the solenoid ?

Yes....the new valve is also 24vac.

 

I have been measuring the power in the wires feeding the solenoid, not on the actual solenoid. How would I do that?

Thanks

 

Also,

I was reading on an Aprilaire blog that the humidistat is continously powered " We have two digital humidifier controls, and there weren’t any indicators as to which one you had. Both of them are looking for continuous 24v to power them and an intermittent 24v to tell them when your furnace is active.

Is this correct? I am not seeing any voltage on the humidistat unless the furnace is on. But regardless, if I am seeing voltage in the wires going to the solenoid it should not matter??

 

An electronic humidistat (60, 62) is continuously powered. You didn't say what you have.

You have two wires going into solenoid. There should be two wirenutted connections there connecting your wiring to the humidifier. Don't just check the incoming wires for power. Check them connected to the humidifier. You need to check for 24vac with the solenoid connected.

 

Interesting, so when the solenoid is attached I am getting a zero volt reading.

The humidistat is model 884021BS

 

And found another thread that mentioned shorting the wires at the humidistat...I did so and had water flowing. Sooo what does this mean???

 

Ahhh.... that's why I needed you to check it with the solenoid connected.

The humidistat is bad. It's probably stuffed full of dirt and lint if it's a duct mounted model.

 

Awesome..thanks for the help. I guess I assumed if it is 24V in the wires that's what you got. Anyway, It is indeed mounted on the duct and I also realized that I had the ducts cleaned for the first time in a 100 years, that could have helped as well. Will order a replacement and check back in.