Annoying Humming & Loud Airflow
I just recently moved into a brand new condo where they have installed a brand new Geothermal ClimateMaster Genesis heat pump unit. It is 30,000 BTUs, I believe. Whenever the fan is blowing, the air flow seems much greater than any of the other condos that I've visited that have the same unit (the A/C doesn't have to be on - it's coming from the fan itself). The problem is that is that there is an annoying humming accompanying it. The duct is exposed (it is a "contemporary loft"), and it comes from the HVAC unit right in my bedroom, so I can really hear the humming, particularly when I'm lying in bed trying to sleep. I tried setting the fan to LOW, but that didn't seem to make much of a difference. I spoke with the guy who installed it, and he doesn't really seem to know what to do. He proposed re-routing the duct so that the air has to travel a longer distance before it gets to a vent, but he quoted quite a bit of $$$ for that. I don't believe that will work becuase I can still hear the humming coming out of a register about 35 feet away at the end of the duct!
Any suggestions? I think he's just messed up the installation somewhere, and thinks charging me another $$$ to dampen the sound is "worth a shot."
Last edited by ms244; 07-02-2008 at 05:12 PM.
Did he come out and listen to it?
Is it metal ducts ?
When the fan is off do you still here it?
Yes, he came out and listened to it. He tried a few things (took the cap off the end of the duct at the terminal end to "remove static", for example), but none of them worked.
It is a metal duct with a maximum diameter of about 15".
Nope, I don't hear anything when the fan is off.
He said I should try tying a string around the flexduct that goes from the HVAC unit to the duct to try to choke it off and slow down the fan. That seemed like it might be destructive in the long run? He suggested I also try putting a piece of cardboard over where the filter goes to try to slow down the fan that way. It makes this same noise whether the filter is on or off. Oh, and I disconnected the flexduct from the metal duct, and the humming persisted - didn't seem to do much at all.
The humming could be a transformer,which would continue with the fan off,so that would be an easy fix.
Hard to tell from here.
From your description,disconnecting the flex duct ,would have stopped or decreased the air flow.
Do you mean round flex duct or a flex connecter at the duct and the indoor unit.
You should remove the prices from your post, it is against the rules here.
Originally Posted by ms244
Thanks so much for your prompt responses.
The humming stops once the unit kicks off, so it's probably not the transformer, based on what you said.
Sorry - when I say flex duct, I mean the round flex duct that connects the indoor unit with the metal duct that feeds the condo. It basically delivers air from the indoor unit to the duct. I disconnected this to see whether there was something in the metal duct that was causing the humming, but the humming seems to be coming directly from the unit.
The installer seems to think "static" plays a role in all of this, but I don't know what that means. Any ideas?
Okay ,sounds like it may be fan noise from the indoor blower,if so more flex ,trunk or branches will help absorb it.Replacing some of the trunk would make more sense as it would reduce noise at all branches and grilles.
Any noise from the return grilles?
Can you post pics of the indoor unit and connecting ducts ,plus the model number and main duct sizes at the unit?
Could just be on a higher fan speed then needed ,if air flow is lower in other condos withe the same system.
I don't really seem to be getting that much noise from the return grilles. ALL of the units are using the same fan speed, and they're all quiet except mine. Mine has a slightly different duct set up, but, as I said, the noise seems to be coming from the unit and not the duct itself.
I need to take off to run some errands, but I'll definitely try getting you those specs ASAP.
post a buch of pictures to help us see it a little better........
you have out attention....thats for sure.
If its coming from the unit, are all the panels properly secured? Are all the pluenums hooked into the unit properly sealed?
I fully support the military and the War on Terrorism.
If you don't know, then don't do. If you don't know and still do, then be prepared to pay someone else a lot to undo what you did and then do it right.
If you do know, then do. But do it right. Otherwise, you may not be doing it long.
Just curious ,how do you know the fan speed of all the other condos?
Originally Posted by ms244
Is fan secured properly? Also is the unit level ? A slight vibration on the decking may transfer through the duct system.
It's a brand new complex, and they aren't yet occupied. The guy who installed them told me they were on medium. Good question.
Originally Posted by dash
Strange that he would tell youto restrict the duct instead of moving the speed to low.Not saying either would solve the noise,just strange that if he thought less air flow would,he didn't lower it.
I'd cll and speak with the owner/manager and see if s/he might have some ideas or take a look at it.