Furnace Humidifier installed, slight buzzing noise now

[BTRY B 529th FA BN]

I bought a Honeywell HE360A furnace humidifier early 2020, just recently got to having it installed. Never noticed any buzzing coming from the furnace before but now I'm hearing a slight buzzing noise coming from the humidifier unit. It's very faint but can be heard 3-5' away if you listen closely with everything else in the basement turned off.

During the installation the sub contractors did the hardware install but when wiring it they blew the transistors on the furnace and humidifier unit. The contractor came by later and diagnosed the issue and fixed the furnace transistor and the next day dropped off a new HE360A. Last night he came by and installed it and it seems to all be working fine except I now notice the faint slight buzzing noise. Any guesses on what it might be?

 

[mindless1]

Does the buzzing sound like the air duct is vibrating or like an electric sound, then probably the humidifier valve solenoid?

If it's the duct you can beat a dent into it or shim or foam tape to stop it. If it's the humidifier solenoid, some do make a faint noise but if you think it's defective then you should have the installer come back to take a look.

OR, did whatever they damaged, not get repaired properly and the buzzing noise is on a furnace control or power board? Identify and tell us where the buzzing is coming from.

Are you certain you are using the correct terminology when you wrote that they blew the transistors? Normally any transistors are discrete parts soldered to a larger circuit board and no normal HVAC tech would isolate to that level, would replace the whole board if it was felt to be faulty and would never know if it was a transistor or something else on the board that caused it to fail to operate. I'd sooner think it might have been a fuse that blew and needed replaced.

 

[bbhaag]

Yeah I was thinking the same thing about it being the solenoid. Whole house humidifiers are pretty simple. The only electrical part of them is the solenoid opening to allow water through when the humidistat calls for it.
Like MIndless1 mentioned it would be helpful if you could actually trace what is making the noise and maybe even post a pic of it.

Just out of curiosity did you have a humidistat installed at the same time or did your contractor wire it to your exiting thermostat?

 

[BTRY B 529th FA BN]

Could it be the 'Transformer'? Apparently April Aire doesn't have them but the Honeywell has one on their model I bought.

When I first heard it nothing was running in the basement, no lights on, nothing else could of been buzzing. Like I said it's extremely faint. When I unplugged the Humidifier the buzzing went away.

There's a humidity sensor on the return duct, the humidifier is after the furnace.

 

[mindless1]

A transformer can make a buzzing sound, only way to be sure is poke around to isolate the source. A severe buzzing could eventually wear the insulation off the wire but a slight buzzing isn't necessarily a sign of a problem besides the undesirability of hearing it.

 

[BTRY B 529th FA BN]

Is there a way to control the amount of water being used? I'm seeing a fairly fast drip, almost a slight stream of water coming out of the drain tube. There's a valve that's tapped into the hot water line and I was wondering if closing it a little bit would change the amount of water flowing through the filter.

 

[mindless1]

Yes it is possible to reduce the flow with the valve, though sometimes if those valves are not completely open, they more easily leak.

It would seem that whoever set it up did not do so correctly. Verify that the solenoid is only opening when the blower is on.

Silly question but I assume you mean water is coming out of the drain tube going to the pan on the humidifier itself, not the main furnace drain? Or did they somehow plumb that together? Main furnace drain could just be water as a combustion byproduct.

Normally a humidifier also has a humidity adjustment. If the air is not very dry and that is turned up too high that can also explain why less water from the humidifier is being put into the air and more going down the drain.

 

[bbhaag]

^^Yup you should be able to adjust the amount of water flowing through the pad so as not to have a steady stream coming out the drain line. To much water flowing through will just shorten the life of your pad.

I also had the same question and didn't get an answer from the OP so I doubt you will but anyway you're correct. The humidifier should not turn on every time their is a call for heat. That's bad news and will eventually lead to condensation build up around the window sills and mold/mildew after that.

 

[BTRY B 529th FA BN]

Yes it is possible to reduce the flow with the valve, though sometimes if those valves are not completely open, they more easily leak.

It would seem that whoever set it up did not do so correctly. Verify that the solenoid is only opening when the blower is on.

Silly question but I assume you mean water is coming out of the drain tube going to the pan on the humidifier itself, not the main furnace drain? Or did they somehow plumb that together? Main furnace drain could just be water as a combustion byproduct.

Normally a humidifier also has a humidity adjustment. If the air is not very dry and that is turned up too high that can also explain why less water from the humidifier is being put into the air and more going down the drain.

The humidifier only turns on when the furnace/blower is running and will shut off when it stops, so that seems to me that it's installed correctly. It doesn't turn on all the time, so I assume it works when a sensor detects the need to run the humidifier.

The valve is also tapped in on the top of the hot water line. I was told that if they are on the bottom they tend to rust out quicker. So I can just turn it clock-wise to reduce the flow? I'm just worried, you know every time you touch an old valve it ends up leaking, hah, oof. I just wanna be sure it will work and that it won't leak: I guess I'll just have to try it, if that will work.

The humidity adjuster is set according to the outside temp. The more often the furnace runs I assume the lower you want the setting, so it doesn't use up at much water.


Here is the drain valve:

 

[bbhaag]

The humidifier only turns on when the furnace/blower is running and will shut off when it stops, so that seems to me that it's installed correctly.

Um no that doesn't mean it is installed correctly. The humidifier should only turn on when there is a call for heat AND the humidity inside your home is below the set point on your humidistat/thermostat. Outside humidity/temperature should have no bearing on when the humidifier turns on because the outside humidity will be different than the humidity level inside your home.

 

[BTRY B 529th FA BN]

Um no that doesn't mean it is installed correctly. The humidifier should only turn on when there is a call for heat AND the humidity inside your home is below the set point on your humidistat/thermostat. Outside humidity/temperature should have no bearing on when the humidifier turns on because the outside humidity will be different than the humidity level inside your home.

Edited the post above but here,

It doesn't turn on all the time, so I assume it works when a sensor detects the need to run the humidifier.

 

[bbhaag]

So what is the set point for your humidifier? I also have a humidifier installed and the set point on my Nest is at 30%. You should be able to adjust the % of humidity in your home either through a humidistat or your thermostat. Not sure were you are located but here in the Midwest to high of humidity levels inside the home can lead to issues.

Did your installer not show you how to adjust the set point of your humidifier?

 

[BTRY B 529th FA BN]

It's set at 40%. A family member has the same humidifier and it needs to be set lower than 40% or the windows will develop condensation, with mine it doesn't. I have a thermometer with a humidity sensor and it's between 27-30% humidity in the house.

 

[mindless1]

Something is less than ideal still because the valve is meant to be fully open and it only drips onto the mesh pad the air blows across at a rate barely more (ideally equal to but that is hardly possible as a factory design) than it evaporates off. I mean for a typical humidifier, I suppose it is possible that they stopped trying to regulate flow and left that burden on the installer. Is the mesh installed, positioned correctly so the water goes through it?

Heh, here is an absurd question: Is the mesh pad still in the plastic bag it came in from the factory? Just wondering if this was a rush job and it was never taken out of the bag so water just rolls off.

Do you have very high water pressure? I suppose even if you do, a regulator for only that reason could be excessive if simply shutting the valve some does the trick.

Some of them do have the humidity adjustment based on outside temperature based on their best guess at how often the furnace will run to achieve a tolerable indoor temperature. My very old humidifier is set up this way but it doesn't lose excessive water out the drip pan. Sensing indoor humidity would be more precise but I can't complain much because it still works "well enough" after all this time.

 

[BTRY B 529th FA BN]

Something is less than ideal still because the valve is meant to be fully open and it only drips onto the mesh pad the air blows across at a rate barely more (ideally equal to but that is hardly possible as a factory design) than it evaporates off. I mean for a typical humidifier, I suppose it is possible that they stopped trying to regulate flow and left that burden on the installer. Is the mesh installed, positioned correctly so the water goes through it?

Heh, here is an absurd question: Is the mesh pad still in the plastic bag it came in from the factory? Just wondering if this was a rush job and it was never taken out of the bag so water just rolls off.

Do you have very high water pressure? I suppose even if you do, a regulator for only that reason could be excessive if simply shutting the valve some does the trick.

Some of them do have the humidity adjustment based on outside temperature based on their best guess at how often the furnace will run to achieve a tolerable indoor temperature. My very old humidifier is set up this way but it doesn't lose excessive water out the drip pan. Sensing indoor humidity would be more precise but I can't complain much because it still works "well enough" after all this time.

I agree. It doesn't seem right. I'm guessing it's the filter. I bought a spare filter a while ago and the material on the metal mesh feels different than the one that came with the unit. I never touched the original one that was installed with the humidifier. However the mesh filter appears that it can be universally installed into the mounting frame. The mounting frame only goes in one way.

The tap into the hot water line is about 2' away from the top of the water tank. The tank is actually installed wrong. Has a shut off on the hot water line which is a no-no, and it should have a pressure badder also.

I took a video of the humidifier drain while running with the valve wide open. It is really pouring out so I'll have to adjust it from the valve; unfortunately I can't upload the video here. I don't have a hosting page nor want to create one.

 

[mindless1]

If you have a google account, you could just put the video on google drive and give us a shared link... a while back googledrive defaulted to non-shared links IIRC so that is something to watch out for.

If comparing the coating on an old filter, on mine it seems to lift up and get more porous looking with age. I am sure it's just the coating + mineral deposits, not fungus. Mine looks similar to yours except half the height but twice the thickness.

 

[BTRY B 529th FA BN]

I'll probably change the filter in a couple of days and see how things go. Also there's a vent, if you're facing towards the humidifier, on the left part of the duct to allow heat into the basement. I've had that open half way. That might have been allowing cold air to be pulled through the humidifier, but it seems unlikely. I'll keep it closed and see if that helps bring more humidity through the house. As it is, the outside temps recently dropped to around 30s and the humidity in the house dropped to 25% from ~30% which I feel shouldn't be happening. Seems to be a drastic change for such a little drop in temps. Dead winter I'm sure there will be days close to 0*F and extrapolating from the recent drop I'm not optimistic about it's performance during then. I'm really hoping it's just the filter.

 

[mindless1]

Any vent before the humidifier is a bad setup, I'd patch that up and move it to be after it.