multiple leaking radiators below steam intake valve

[Deleted User]

So we were down in the basement today fixing missing insulation. As we were making our way around we noticed petroleum like stains coming from 3 radiators on the first floor. It didn't really seem like water.
Basically the area around the threads had a trail leading run down around the joint below the radiators on the basement side. They weren't really wet but it was definitely noticeable that there was some kind of streak there. We looked at these last week and did not have this issue.

Anyway, we did remove a radiator from the system this week because we needed to replace the floor in a bathroom. We shut off the intake valve to that radiator when we removed it. It hasn't been put back into the system because we're not down with that floor. I'm wondering if that had something to do with it maybe. I feel like its too much of a coincidence that these all start showing signs of leaking at the same time.

acwagner

Can you post a photo of these leaks?

[Deleted User]

They are dry to the touch. W never noticed these before. It's almost like nail polish dried on the pipe.

acwagner

Can you tell where the leaks originate? Somewhere on the supply valve to the radiator?

Fred

What's the pressuretrol set at? When was the last time you took the Pressuretrol off and cleaned out the Pigtail (looped pipe the Pressuretrol is mounted on)? If it is clogged, the Pressuretrol can't see the system pressure and by having that radiator off of the system, you just may have created an over-sized system that is building pressure. Clean the pigtail and put that radiator back in as soon as is reasonably possible.

[Deleted User]

The pressuretrol is set at just about 0.5 psi. Pretty much the lowest you can go. The pigtail was probably cleaned 2ish years ago.

It's hard to tell where the leaks are coming from, it may be from around the shutoff valve to the radiators.

Fred

Two years ago? It needs to be cleaned. I had my pressure run away once, years ago, leaks appeared around the valve stems, around the vent stems, even around the bonnets on the valves. It's amazing what shows up with 5 or more pounds of pressure.

acwagner

Looks like Fred beat me to it. Anyways, on old valves they can start to leak around the stem that connects the handle to the valve. Look closely at the valves and see if you can see water or bubbling from there when the system is on. It's an easy fix if that's where the leak is.

I agree with @Fred that having the radiator off is causing a temporary situation where the pressure in your system is operating higher than it has been and is exposing these weak points in your system. So it's probably not a coincidence you're seeing this now with that bathroom radiator disconnected.

Definitely check your pigtail. Also, what are the settings specifically on your pressuretrol?

[Deleted User]

The pressuretrol is set to just about 0.5 psi cut in. Pretty much as low as possible. We'll see if we can get to cleaning the pigtail tomorrow.

acwagner

What's the cut-out pressure set at?

Fred

Inside the Pressuretrol there is a white wheel (the differential) it needs to be set to "1". The actual system pressure is the Cut-in plus the Differential (If the Pressuretrol is a gray box)

Abracadabra

It's almost like nail polish dried on the pipe.

Maybe polyurethene from when the wood floor above was refinished?

RomanGK_26986764589

Yep, I also had dried leaks on the radiator run outs after we refinished the floors!

[Deleted User]

The dial inside the pressuretrol was set to 1 and the cut-in on the outside was set to 0.5. The pigtail has been cleaned. It wasn't really dirty. The pressure gauge isn't really changing. It seems to be stuck around 1 but I guess it could be because the pressure is really low.

Anyway, we really need to get on the yearly maintenance. It hasn't been done consistently in the last couple of years.

I do think that perhaps the 'leaks' was some sort of poly because if I put my finger to it and then smell it smells like something oil based. Phew.

acwagner

Sounds like your pressure settings are in the zone. Some of us like to put 0-3 or 0-5 PSI gauges on so we can see what the actual operating pressure is. The standard 30PSI gauges don't register at the low pressures these systems normally operate at.

The poly is a good explanation. Spot on @Abracadabra

You might want to check the valves, in any case, for leaks.