Question about Aprilaire 550 Humidifier

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There is no water getting to the unit and the water line is ok

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Hello, first check the strainer on the inlet side of the solenoid valve, if there is sediment built up clean it and reinstall, if the strainer is clean and you are getting 24 volts to the solenoid valve and it is not allowing water thru replace it.

Posted on Mar 31, 2011

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Aprilaire 600 - water flow stopped to unit when running - chk'd lines and all ok - will run in manual mode on hudmidifer control (pt # 56) but with outside temp sensor connected seems to not register to...

Doesn't the float valve on the water sump control the level of water in the sump?

Do you have water to the valve? (Like loose the nut on the tubing-- does water come squirting out?)

If not, you can't get humidity into your system, without water in that sump or pan!
The mat can be turning-- but if it is not SOAKING WET!-- you get no humidity in the house!.

Could the main shut off valve be plugged?--

Bottom line is-- the Humidifier needs a steady supply of water-- It will go thru gallons of water every day, this time of the year!

Mack B

Jan 26, 2011 | Aprilaire Humidifiers

1 Answer

Water flow ok to side valve. no waer flow to top of 1042-l unit. valve extremely hot. is there an expert service maitenance available in montreal

Replacing this solinoid valve is not hard to do. This is something the homeowner can accomplished with small hand tools. Turn power off at the furnace and the inlet water off at the saddle valve.Remove the water line at the valve and the connector exiting the valve. Remove the two screws and the valve is off the unit. Armed with the make and model number of the unit goggle the manufacture with the model number and order your replacement valve on-line. Install the new valve opposite of which the old valve was removed or per manufactures instructions that may come with the new valve you orderd.

Jan 23, 2011 | General Filters 1042-LH Humidifier

1 Answer

I have an apprilaire 700. I pulled the plug on it because the water department had a main break. Since then the unit does not work. I connected the brown wires that come from the unit while the furnace...

If water main break you may have a little debris in the water line. There is a very small orifice in the solenoid and would not be hard to plug. Shut water off and pull line off humidifier and see if you can blow out line.

Jan 16, 2011 | Aprilaire 700 Humidifier

1 Answer

The solenoid for Model 600 was installed upside down--the inlet is closest to the floor. Is this OK? Also no in-line strainer. I confirmed water to the solenoid, but in Test mode w/ feeder tube...

The solenoid valve unit will work upside down however, I am concerned that the tech that installed the unit might have installed it backwards. Look on the side of the valve the solenoid is connected to and you should find an arrow. Thats the direction of the water flow.A strainer helps keep the valve clean however if there is dirt in the valve it would be stuck opened not closed. Make sure the solenoid is getting power via float valve. If the solenoid is getting power you can tell by touching the top of the solenoid with a metal non magnetic screw driver. It will pull the screw driver like a magnet. Good luck

Jan 15, 2011 | Aprilaire 600 Humidifier

1 Answer

My Aprilaire is connected to the Hot water line and it stops working in approx 1 month. I just had plumbing work done and my new plumber said the problem it that it should be connected to the Cold Water...

Your plumber is correct your unit should be plumbed with cold water.
Easy fix if you need to do it yourself.
More than likely they have a 1/4 inch line taped into a 1/2 inch copper line near your furnace.
Simply shut off the tap on the undesired line and disconnect the 1/4 inch line.
Install a new tap on the cold water side and reintall supply line to the unit.

Do not remove the old tap on the hot water line simply shut it off because it puctures the line, hence the tap.

Jan 02, 2010 | Aprilaire 550 Humidifier

2 Answers

Orifice clogs to Aprilaire 600 look at page thirteen in this manual there is allready a inline filter on the unit. hope this helps

Jan 06, 2009 | Aprilaire 600 Humidifier

2 Answers

Routing waterline to pad

1/4" flexible copper pipe. Tap into your cold water line using the included saddle valve (pierces the pipe), attach the 1/4" flexible copper pipe to the saddle valve on the cold water pipe and the solenoid valve on humidifier unit using the included compression fittings. Tada!

Dec 10, 2008 | Aprilaire 550 Humidifier

1 Answer

Water does not get to Humidifier. Goes from source to motor.

That is not a 'motor' on the side of the humidifier housing, it is a solenoid valve. The water feeds in to one side and exits the other side to a tube that feeds in to the top of the humidifier unit. The valve opens and allows water to flow when electrical power is applied to the valve

The valve electircal requirement may be either 120 vac or 24 vac. Power typically is switched on and off by a Humidistat control. The power feed to the Humidistat may come from a small transformer if the valve is a 24 vac unit, or directly from a furnace connection if the valve is a 120 vac unit. There are many variations, though.

A qualified licensed eletrician should check the power feed to the valve. If there is no power feed to the valve then he can trace back to the point of failure and correct the issue ... but he must also check for additional issues with the valve itself, as noted below.

Other possibles reasons for solenoid valve failure:

If power feed to the valve tests ok, then the coil inside the solenoid may be 'open' (bad, no continuity). The electrician can test the coil by checking resistance or continuity of the coil.

A non-electrical problem is that the valve path may be blocked by hardwater mineral build-up or other foreign material that flowed through the water line.

The solenoid valve must be replaced if either of the above is true with your valve.

Remember, use only a quailified licensed electrician!

Nov 24, 2008 | General Filters 1042-LH Humidifier

1 Answer

Water not running through humidifier

Sounds as if you feel the problem is the saddle valve. Check to see if water is available at the humidifier. Close the saddle valve, disconnect the water line at the humidifier side, then slowly turn the saddle valve back on. If you never see water, then correct the saddle valve. You can get details here:
If you are getting water, but dont think that the unit is operating try sending 24VAC directly to the hunidifier and see if it operates, bypass the humidistat etc.

Dec 08, 2007 | Honeywell HE220A1019 Whole House...

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