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Lots of water run-off from Aprilaire 760 Humidifier

Our Aprilaire 760 seems to put out a lot of water when the gas furnace runs (and slightly thereafter). Is this normal? Should we shut off the humidifier? Where is the switch, inside the humidifier panel? Our drain seems to be filling rather quickly. Thanks. DEL

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Re: Lots of water run-off from Aprilaire 760 Humidifier

HI would check the filter in side might need changing or cleaning clean out wter tray in side, it could be just a blocked filter , hope this helps

Posted on Feb 02, 2010

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Water and motor always run on Aprilaire 760, even when furnace is off.

Hope this solves your problem, look for the humidistat, it should be located on cold air return duct near furnace, make sure it is not set in the on position, if it is, then this is why it is staying on, please set humidistat any where from 20 to 35%, never over 40%. If the humidistat is set properly and is still running, you may have a electrical problem, humidifier circuit should only receive power(24 volts) when the indoor blower motor of furnace receives power, also if you have galvanized plumbing in your home, you may have a piece of rust or lime deposit in the humidifier solenoid valve preventing it from closing, turn water off to humidifier and disconnect water supply line entering solenoid valve inspect & clean protector screen. Good luck.

Mar 03, 2010 | Aprilaire 700 Humidifier

1 Answer

Loud vibrating noise when the furnace blower starts up.

Try closing damper slightly between humidifier and furnace????

Feb 03, 2010 | Aprilaire 550 Humidifier

1 Answer

Aprilaire 600 humidier: water continuously runs

sounds like you may have it wired to a continuous power source vs one that shuts off with the furnace. The most common wiring is red to C & white to W

Jan 08, 2010 | Aprilaire 600 Humidifier

1 Answer

Water running after heater shut off in humidifier

Hi check power at transformer / valve on water line could be stuck open clean valve out or transformer holding valve open

Dec 31, 2009 | Aprilaire 558 Humidifier

1 Answer

Aprilaire 760 keeps running.

The humidifier should not turn on untill the furnace blower starts. Since the fan stays on. does the solenoid valve also stay on? If they both stay on you probably have a bad humidistat. If only the blower stays on then the circuit bourd in the humidifier is defective.
Good luck
HVAC Teacher

Feb 06, 2009 | Aprilaire 700 Humidifier

1 Answer

Water runs when furnace is off, but stops when furnace is on.

the 760 humidifier does not need a transformer wired externally. the 760 has its' own 24v transformer inside the fan compartment. this transformer will provide the power to enrgize the water solenoid as needed. it sounds like to me the additional trasnformer is hot all the time. when the furnace comes on, the unit gets power and the internal transformer is cancelling the power from the external transformer. this would explain why it quits running when the heat is on. since the external transformer is hot all time, when the heat shuts off, the solenoid is getting energized by the external transformer. to make this run correctly, you need to get rid of the external transformer. leave the humidifier high voltage wires hooked up so they are only hot when the furnace runs. if you have a humidistat that has a r and c terminal, you will need to wire these directly to the r and c on the furnace control board and move the switch inside the humidistat to "power". make sure it is not on "bypass". then wire your 2 brown wires from the humidifier to each of the "h" terminals on the humidistat. if you have a humidistat that only has 2 terminals, wire one brown wire to each of the terminals. this should allow it to run properly.

Jan 28, 2009 | Aprilaire 700 Humidifier

1 Answer

Aprilaire model 760

It could be that the humidistat is not calling for humidity. Make sure that you have the dial turned up all the way (as far as it will go, just to test it) and that the blower on the furnace is running - if the unit is properly wired, the water will not run unless the blower on the furnace is running. This should do the trick. If not, the only other thing would be a bad humidistat. Good Luck!

Dec 14, 2008 | Aprilaire 550 Humidifier

1 Answer

Water does not stop.

soliniod may be stuck. you will need a volt meter to test

Dec 13, 2008 | Aprilaire 700 Humidifier

1 Answer

AprilAire 760 not running after installing new circuit board

I called the service company that put in my new furnace (FAmily Heating and Cooling in Detroit, very highly recommend these people)

Anyway they sent out a second service tech who determined that I would be better off having the humidifier wired to go on whenever the furnace fan was running instead of using the humidifier signal from the circuit board on the furnace. After he changed the wiring the unit runs fine. It is pretty likely that the circuit board was bad also.

Nov 27, 2008 | Aprilaire 700 Humidifier

1 Answer

Aprilaire 760 Humidifier water continues to run

You need to determine whether the problem is in the solenoid or in the furnace electronics. You could put a voltmeter on the solenoid connection to see if the furnace is still holding the solenoid open after the blower stops. This will tell you whether it is the solenoid or not.

Feb 18, 2007 | Aprilaire 700 Humidifier

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