Refurbished radiator making bird noises. Not vent?

Tezak

I installed a refurbished radiator over the summer in our bedroom. It was supposedly pressure tested by the supply house I purchased from. I ran the boiler and it makes this bird-like screech basically the entire time it’s on. I don’t think it’s the vent. It’s a vent rite #1 and no matter how I adjust it, the bird noises stay the same.

Is it possible the radiator has a hole? There’s no sign of a leak and I ran it until the vent closed and the radiator got hot all across. It’s under warranty for a year so I can return if necessary. I plan to switch to a different vent next call for heat but may have to wait until tomorrow so I don’t cook the upstairs tenants.

Video here so you can hear the sound. https://youtube.com/shorts/29sgntdeuE4?si=8WEZb0WMQg_vusin

STEAM DOCTOR

Is this the only radiator making noise?

Make sure that the shutoff valve is fully open.

Where any other changes made to the system?

Is this the same radiator that was there before (meaning did you buy a new radiator or did you refurbish one that was there previously)?

Try running the heat without any air vents on, just for kicks.

Tezak

this is the only one making noise. It’s not the same one as before. It replaced a cracked radiator. There were no system changes. The only other new factor is that I used 8-way boiler treatment over the winter and I’m using that treated water now. I will try running with no vents to see what happens.

Tezak

Ok ran it without a vent and did not hear anything. When about half the radiator was hot I screwed in a different vent from the first test, a MOM adjustable with the slowest orifice. When radiator was nearly hot all the way across I started to hear the screeching again.

Some observations: the tapping for the vent seems to be run kind of deep. The vent rite had to screwed in all the way and kind of bottomed out. The MOM felt like it had a good tight fit before being screwed all the way in.

Not sure if there’s a small hole that only leaks when pressurized?

Jamie Hall

And what pressure are you running your system at?

Tezak

@Jamie Hall as low as possible. Having no issues on any other radiators.

Jamie Hall

Just asking — so often we hear of people running steam at a few pounds and wondering why it's noisy…

Tezak

I think I’ll try running it with a plug in the vent tapping next and see what happens

PC7060

https://forum.heatinghelp.com/discussion/comment/1864195#Comment_1864195

What will happen is that radiator won’t heat.

Post a picture of the pressure setting on the boiler.

Tezak

My thought was that if there’s a hole I may hear air escaping

HVACNUT

https://forum.heatinghelp.com/discussion/comment/1864211#Comment_1864211

If it does heat, there's a hole making a hawk screech noise.

BobC

Use extra layers of teflon tape with the vent. - try 6 wraps and use more if you think it may still be bottoming out. It's possible the vent it bottoming out allowing a very tiny amount of steam to escape

Tezak

@BobC i think this was it. I also tightened it way tighter than I typically would ever do for a vent (probably risky). No screeching on this last test. I also think due to factory variation or something the vent-rite just couldn’t get in there snug enough but the MOM seems to be working.

AdmiralYoda

@Tezak Good news, looks like you are on to finding the source of the problem! Good thing it isn't a hole/crack somewhere else as that would be much larger inconvenience.

Although it is annoying to get a refurbished radiator that you need to put some effort towards, a little extra teflon is probably better than shipping it back and forth for another one.

I'd go for some thick teflon tape and as others have said….go nuts with it. Maybe some pipe dope too for good luck.

Tezak

@AdmiralYoda Yeah completely agree. Annoying that it doesn’t “just work” but it would be REALLY annoying to disconnect, return, and roll the dice on another one.

It’s a nice looking radiator too, the matte black rustoleum bbq spray finish turned out pretty good.

mattmia2

Kinda late now, but moving a small mirror around it and seeing where it fogs could help you find the leak. Also a mechanic's stethoscope or a piece of small tubing in your ear.