Why are my FLOW valves noisy when the heat turns on? I have a hot water oil furnace with 2 zones. I purged them, but maybe I didn't do it right or good enough? There is about 15 lbs of pressure in the system. The hot water goes up through the flow vavles first, then through the system back down through the circulator pumps then back into the furnace.

Hey Rick...

Not sure what you mean exactly here.. Are you saying that the heating system is noisy upstairs at the radiators/baseboard during operation or are you saying that the flow control valves themselves are noisy ONLY at the startup of cycle?

Most noises associated with these systems focus around combustion issues or around excessive AIR in the system.

Let me know more here... may have a few ideas.. ;)

MARK

Rick, also, make sure the valves are open all the way... Partially closed valve will produce noise due to increased friction.

The flow valves are chattering and you can hear water running through the radiators.

Rick...

Go the radiators and open the bleeder valves (vents)... remove at least 1/2-1 cup of water or so from each radiator... or until air stop spurting out.

Let me know if that improves the chattering. It should not only improve the chattering but the noisy radiators as well... ;)

MARK

I'm sorry. I said radiators, they are not radiators, they are baseboard and do not have bleeder valves.

Rick

You might have to look around to find the air vent or vents. They should be located at the HIGHEST point in the system if the system was installed correctly. How many stories high is the home? You might have to increase the water pressure on a temp basis depending upon the height to force the air out.

What was the original problem with the system?

Hey Rick...

Look for vents as suggested by hvac100... let us know what you find. If lucky, you will find a vent or two to purge air from the highest points in system.

I also wonder if you have a some shutoffs and some boiler drains back at the boiler that will allow you to isolate each individual zone and bleed air/water from each zone so that you can remove air in this manner?

Let us know...

Thanks...

MARK

I repurged the system again last night really good and that seemed to take care of it.
Thanks,

Rick

Good job, glad you took care of it. Hope all works well for years to come.

Whenever I hear about "chattering" flow control... almost always air in system!

Good for you Rick!

You can always add a high vent to the system so it will be easier the next time.