HVAC experts

[CM5878]

I have a question for those in HVAC are those that are knowlegeable in it. I bought my home five years ago and the home has forced hot air along with a Aprilaire 550 humidifier built into the cold vent. When I turn the dial from the off position on the humidifier, I hear the unit click but thats all she wrote. When the heat comes on, I dont see any water coming thru the drain tube. It doesnt help either that the unit is at least 10 years old. Any hints or tips? And yes its plugged in lol:beer:

 

[007snake]

I am no expert, but did you check to make sure the valve on the water line is turned open.

 

[CM5878]

That I did not check. I noticed theres some sort of contraption at base of the duct which has something to do with the humidifier. The one end of the drain tube goes into this 'tank', which has some sort of plug which pops off. So im unsure if that needs to be filled with water or not.

 

[SLPRCTM]

What you have is referred to as a "flow through humidifier" The unit has a solenoid on the water line that when open, feeds water to a spray bar on top of the media material inside. The warm air from the supply side of the furnace, passes through the media, absorbing moisture and into the return air. First, make sure the water to the unit is turned on. The device it drains into might be a condensate pump to pump out any excess water from the humidifier. If you can take a pic for me to be able to verify what you have, that would be helpful. Most condensate pumps have a safety built-in to prevent any equipment using them from operating in the event of a pump failure. If you are handy with a multimeter, you can check for 24-28 volts AC current at the solenoid. If there is power at the solenoid then either the water is not turned on or the orifice in the solenoid or supply lines inside the humidifier are clogged. If there is no power, then either the humidistat is not functioning correctly or something is disconnected along the way.

Please feel free to ask me if you have any questions or need further help. I have been doing this since I was 10yrs old and have been a tech now for almost 20 years.

Good Luck!

 

[Mr. Mach-ete]

10 years with no service? Most likely the humidifier has so much scale build up on the interior it will need to be disassembled, cleaned thoroughly, reassembled and checked for performance.

Most humidifiers are easy to disassemble and maintenance. After 10 years I'm sure the water pad will need replacing, you can go on line and purchase a replacement.

The 550 is a pass through humidifier, the head unit is mounted on the supply duct a 6" round pipe is attached to the return duct. There is a water solenoid which is controlled by a humidistat which cycles the solenoid on and off based on humidity levels in the home. Pressurized hot air from the furnace passes over the water medium inside the humidifier and is delivered straight to the return. The newly humidified air is then reintroduced into the return air stream through the 6" pipe and dispersed through out the home. Also, there is a manual damper on the side of the humidifier, make sure the damper is in the open position "winter".

The 550 is a simple humidifier, breaking it down and reassembling it should be fairly easy, even to someone that has never done it before. Disassemble and clean the interior parts in your kitchen sink with warm soapy water, depending on the scale build up you may need to use lime-a-way or something similar. You will most likely need to clean out the interior of the humidifier as well.

Reassemble the humidifier, make sure the interior parts go back the same way they came out. Make sure over flow drains are free flowing and not blocked. The 550 will produce excess water, this water needs to drain off or the unit will leak water possibly damaging the duct, the unit, and the floor below.

Turn the humidistat on. Listen for water flowing inside the humidifier. Most humidifiers are wired so that they won't work unless the fan motor is running in your furnace. Look for excess water flow through the drain line, verify you have no leaks. Cycle the humidistat off, verify the water flow has stopped. If you have no water flow you might check the saddle tap to verify you have water to the unit. If you still have no water flowing there might be an issue with the solenoid valve or fan relay. At this point you might contact a reputable licensed HVAC contractor in your area. Good luck.

 

[CM5878]

Thank you! I'll take a pic later tonight and post what I have. I see no water what so ever so maybe it's something as silly as the water line being turned off. Why it would be is beyond me, but I bought the house and the unit was already installed.

What you have is referred to as a "flow through humidifier" The unit has a solenoid on the water line that when open, feeds water to a spray bar on top of the media material inside. The warm air from the supply side of the furnace, passes through the media, absorbing moisture and into the return air. First, make sure the water to the unit is turned on. The device it drains into might be a condensate pump to pump out any excess water from the humidifier. If you can take a pic for me to be able to verify what you have, that would be helpful. Most condensate pumps have a safety built-in to prevent any equipment using them from operating in the event of a pump failure. If you are handy with a multimeter, you can check for 24-28 volts AC current at the solenoid. If there is power at the solenoid then either the water is not turned on or the orifice in the solenoid or supply lines inside the humidifier are clogged. If there is no power, then either the humidistat is not functioning correctly or something is disconnected along the way.

Please feel free to ask me if you have any questions or need further help. I have been doing this since I was 10yrs old and have been a tech now for almost 20 years.

Good Luck!

 

[CM5878]

Here are several pics that I took of the unit. You can see in the 3rd picture, the red valve but it appears that has nothing to do with the humidifier, though I could be wrong.

 

[SLPRCTM]

The unit on the floor that the pvc pipe goes into is a condensate pump. You can remove the small red plug and pour water into the pump reservoir. Once it is almost full, you should here the pump motor turn on and the water level drop quickly. The small round thing on the bottom of the humidifier is the water solenoid. The two yellow wires are the power to the solenoid. The red handle around to the side in the third picture is the gas shut off to the furnace. The air flow damper is open so air is going throughout he humidifier. Make sure you have water to the unit at the solenoid valve and then check to see if water is making it's way down the media pad inside. There is really no moving parts inside the unit. If there is water to the unit and you here the solenoid "click" then chances are you have a plugged line or orifice in the unit.

On a side note, I would suggest using some duct tape and sealing the opening around your air filter. It is on the intake side and will allow the furnace to bring in any odors or fumes from the furnace area and distribute them throughout the house. Just a strip down each side should do just fine.