Aprilaire 600 not working, need help

[sed6]

All-
Just installed my Aprilaire 600 this past weekend, exactly as instructed. It works proplerly in test mode, but outside of that it never turns on. Reading the trouble shooting tips in the instructions, they'd have me believe the humidity is above 45%, but no way is it that high we have static sparks in the carpet when we walk. It's all wired properly, 24VAC off the furnace whenever the furnace calls for gas (as opposed to fan), and 24VAC going out to the valve. The outdoor sensor is reading right too. The problem exists in both manual and automatic mode. To bypass this problem (and get some blessed humidity into our home) I've had to wire the valve straight to the furnace, bypassing the humidistat altogether (which is about 8" upstream of the intake duct on the humidifier. I could really use some good advice here.
Thanks much,
Scott

[sed6]

Anyone :confused:

[majakdragon]

I would first call the place I bought it and see if it is returnable. It may be the humidistat is bad. Even new things can be broke when you get them. Good luck.

[Ed Imeduc]

Id jump out that outdoor part of the control for get it they dont work right at all. Now you dont want the humidifier comeing on with the just the gas valve . You want it to run and come on only when the blower is on. Get a A50 current sensing relay. This will slip over the blower wire is all. Run a hot to it and on up to the humidistat them to the humidifier. Anytime the blower turns on the humidifier will come on with it.

ED ;)

[hvac4u]

that new stat with the 600 confuses me too at times. have you tried the "manual mode" pin in place of the sensor?

[sed6]

I have tried manual mode, and it makes no difference. I bought the unit online from a retailer so perhaps I do need to give them a call. As far as coming on with the blower as opposed to the gas, I think that logic is backward. If it's wired to come on with the gas, there are several advantages: it won't run in the summer so I don't have to turn it off by closing the bypass damper, also the gas shuts off about 90 seconds before the blower giving the air time to "dry out" any remaining moisture in the pad. With the exception of being able to add humidity by turning on the fan only, I can't think of a single advantage to having it wired to the blower. Mind you I'm no HVAC guru and I woudn't mind hearing differing opinions.

-Scott

[Ed Imeduc]

It should come on and off with the blower get a A50 relay and put it on the blower.


ED ;)

[sensitive]

We can't figure out why our Aprilaire 558 begins to hum after a short period of operation. Any ideas?

[sed6]

It should come on and off with the blower get a A50 relay and put it on the blower.


ED ;)

Ed-You've said this twice now but never given a reason. I appreciate that you might be more experienced in the area than I, but I can't accept a 'because that's how it's always been done' reasoning without some support. Especially in light of what I feel is sound reasoning on my part.

-Scott

[Jay11J]

What brand of furnace you got? Age?

How is the transformer wired? (That come with the huimidfeir)

[Ed Imeduc]

sed6 Yes the humidifer should only come on when the blower is on. If its a bypass or just and input type if the blower is not running it will do no good. It also can like put just water in the duct work there on you. So you have to have the blower on to help take the moisture the humidifier is putting out in the air stream and in to the home. So what in summer you have to close the damper and should turn the water off also. Ill say this I have put in hundreds of them lots of different ones. I have not seen one tell me to tie it in to the gas valve
I've had to wire the valve straight to the furnace, bypassing the humidistat altogether (which is about 8" upstream of the intake duct on the humidifier.
If you do this for sure wire it through the humidistat.
Sensitive on yours. check around the transformer loosen the screws on it are tighten them can help some times. Also check on the water solenoid valve there it can hum also on you.

ED ;)

[mitchella]

well, I've posted about this burner on vs. fan on issue for humidifiers before. In my case, I run the fan 24/7. I think that not much moisture is drawn into the house when the 70 deg. air is being circulated. In fact, I was concerned that the moisture that was might precipitate out and condense in the ductwork. So that is why I want to humidify only when the heat is heating, not just blowing. That being said, I've not wired it yet, it isn't cold enough yet. But one of these evenings, I will set up the relay and wire it up and see if enough humidity is getting into the house to keep the level up. I'll post results later.

[Ed Imeduc]

Just keep in mind. It takes like 5 days or more for the AC to pull the humidity out of a home in the summer so you start to feel cool. So it takes that long to put the humidity in the home for you to feel warm. So you should let it on when the furnac is on.



ED ;)

[sed6]

I appreciate everyone's input, the supplier feels it may be a bad humidistat and is going to get me a new one for my old one :)

-Scott