Hot water pipes humming

JamesRutter

I have this building, that you can hear a humming noise coming from the hot water heat pipes. The boiler has a 3/4hp series 60 B&G pump. If I disconnect the power from the pump, the noise in the apartment goes away. If I remove the coupler from the bearing assembly and motor and just run the motor, I still get the humming noise in the apartments. I replaced the motor and it still hums. It seems like the humming is the sound of the motor being carried on the pipes. Any ideas on getting rid of the humming?

Fred

Is the pump mounted on a solid surface? If you put a rubber pad or some isolation bumpers under where it mounts, you probably will reduce or eliminate the motor noise radiating through the pipes.

JamesRutter

It is suspended by the black steel heat pipes. This is the actual boiler with the motor that is creating the noise.

JUGHNE

That pump/motor is pretty heavy to hang on the pipe without extra support IMO.
Just a hanger on the back end may stop the hum transmission.
A red neck idea is to get a long bungee cord to just get a little weight off the back of the motor. Not too tight, just a nudge up.

HVACNUT

A new motor without the coupling connected, and it still hums?

Is a motor starter being used?
Volts, amps and resistance?

EBEBRATT-Ed

Follow the supply pipe coming off the pump discharge when you come to a pipe hanger put some rubber cushion or armaflex between the hangers and the pipe. Do that with several hangers. If that doesn't work Install flexible pump connectors between the pump and piping. You could probably get away with just 1 on the pump discharge

JamesRutter

thank you all for the advice. When I get back over to that building I will try the suggestions.