Hot water / steam radiator leaking a lot

gritfor29

Hi,

I live in an old city apartment, the radiator in the place looks like this:



I'm a heating/plumbing newb, so my terminology is going to be way off.

The "knob/valve" at the bottom right is fully closed. I assume this is where hot water or steam feeds into the radiator. The radiator is cool to the touch, but it's still making a rattling noise. Every 30 minutes or so, the pipe that's standing on the left side of the radiator (release pipe?) starts bubbling over with cool water. I have a pan under it to catch the water.

I tried opening the knob/valve at the bottom right to see if getting the radiator going again would fix things. The radiator started heating up (lots of noise), but I started getting a massive amount of water coming out of the release pipe every 30 minutes or so. It looked like a faucet had opened. I've turned the bottom right knob/valve off again.

So a few questions:
1. What's going on here - is it possible that the bottom right valve isn't working 100%, so some water is still getting into the radiator, and periodically overflows?
2. Is it dangerous to have the radiator shut off like this? My worry is a potential pressure overload or something like that.
3. Why would there be so much overflow of water when I do have the bottom right knob/valve open in a "normal" functioning state?

Thanks for your help

Steamhead

You are correct. The valve is not shutting completely, so some steam is getting in and condensing into water. But the water can't get out since the valve is mostly closed.

Opening the valve while the steam is up allows steam to hit the trapped water, causing banging.

Good luck trying to get the landlord to fix this.

KC_Jones

It is a common misconception that you can "turn off" a steam radiator or convector with that valve. Those valves are old and typically not maintained. I rebuilt a few in my house and some still had the remnants of what appeared to be leather on the seal. You either leave the valve fully open all the time and the water issue MIGHT stop or you get the landlord to stop flushing all the tenants money down the toilet and fix the system. I assume you want it off because it's too hot? If you truly want it off all the time the only thing you can do is take the vent out of the side opposite the valve and put a pipe plug in it's place. It is typically 1/8" pipe thread. Oh and if you do that leave the valve open. Also you must do this when you know the heat isn't running. The other alternative is get the tenants together to fix the system. If people are too hot and/or too cold the system isn't functioning correctly and should be fixed (see my money comment above). Good luck.

ChicagoCooperator

Judging from the every 30 minutes, you're on a 2 cycle per hour control which is correct for convectors. I'm wondering if somebody put a radiator vent rather than a convector vent on the convector. Since you are in New York call your super.

Fred

I also assume the convector is tilted back slightly towards the steam pipe. If it's piped the way the pictures are drawn, it would be easy for it to get tilted the wrong way, causing condensate to pool at the vent end of the convector.

gritfor29

Thanks for the answers, all. Updated image of what the "thing" at the end of the standing pipe looks like. It's leaking water out the top of it. It has the following inscribed on it:

"No. 43 Air Valve, Max. Press. 10 PSI Hoffman Specialty"

When I first took the radiator cover off, there was an additional (broken?) one of those just lying on the floor in there, kind of funny.

When I have the bottom valve fully open, then water comes shooting out of there at an alarming rate. So I'm afraid to leave the bottom valve fully open now. Should I try leaving it open for a few hours? Would the excess water somehow level off at some point if open long enough?

Final question - is this at all dangerous, could messing about with the valves somehow create enough pressure to explode? It would be a sad way to go.

Thanks!

Abracadabra

How about an actual picture of the convector so we can see if something else is going on? What's the pressuretrol/vaporstat set at?

Fred

That Hoffman #43 is a Convector vent so it should work. There is no danger of building too much pressure or causing an explosion but, if it spews water long enough, it could get to a point where the water gets scaulding hot or is starts spewing steam. There is a problem that is causing the water to come out that vent. I'd leave the valve off and get the Landlord to correct the problem.
Did you check the pitch of the convector? Is it tilted back towards the supply pipe?

KC_Jones

It is most likely full of water from having the valve closed. It will spew water for a while then the steam will come out. The vent is either bad or the pressure in the system is way too high. Either way as Fred said get the landlord involved to remedy the situation. If steam starts pouring out it's not the pressure it's the possible burns that could be involved.

ChicagoCooperator

What you could do, if you wan to do something yourself, is time the cycles, which you seem to have and right before the steam comes back up, shut the valves, which, hopefully will isolate the convector which should be empty at that point.

Steamhead

https://www.youtube.com/watch?v=anwy2MPT5RE

RobG

@BrooM , the more that you post about Verano, the more it makes me want to never use your product! Buy an ad!