Author Topic: Loud Roof Top Hot Water Recirculating Pump  (Read 5168 times)


  • Guest
Loud Roof Top Hot Water Recirculating Pump
« on: December 13, 2009, 09:08:31 AM »
I can hear the hot water recirculating motor in my apartment. It's a loud hum. The pipe that the motor feeds from goes through my unit though oddly enough the noise is loudest down the pipe (in my unit), away from where it enters and away from the motor. I have 20ft high ceilings with exposed pipes.

When it shuts off it sounds like a cat meowing, in need of help.

Maintenance has tried to grease the motor to eliminate the cat noise -no luck. I took a look at the motor and there is a crack on a piece of rubber covering its "axle" (or whatever its called).

The main pipe coming through my unit is not completely sealed off at the ceiling (i.e. there's space between the pipe and the hole as it goes through the ceiling). Though I don't think this makes a difference, as I'm hearing the actual motor not the sound of water pumping.

Is there anything that can be done (internal or external) to minimize the humming? Is it normal for a recirculating motor to make this noise? Are some brands quieter than others?

Thanks for any help.

Randy S

  • Senior Soundproofing Technical Specialist
  • Global Moderator
  • *****
  • Posts: 815
    • Super Soundproofing Co
Re: Loud Roof Top Hot Water Recirculating Pump
« Reply #1 on: February 10, 2010, 11:38:22 PM »
Start off by caulking around the pipe where it enters your unit. Depending on how much reduction that provides, you might have to cover all the exposed pipes with closed cell foam pipe insulation.

Randy Sieg

Super Soundproofing Co
Ph. 760-752-3030