Radiator not working properly

jc2lite1

I recently noticed a radiator not working. I took of the valve to ensure it wasn't stuck shut and it wasn't. I replaced the cage unit in the trap and still not working. I removed the cage unit, turned up the thermostat and still not getting heat. I opened up the trap and could hear gurgling and put the cover back on and bam, here came the steam. Any thoughts. This is a 2 pipe steam boiler vacuum system.

EBEBRATT-Ed

If steam came to the trap with the trap opened up, then your supply sounds ok. Are you sure you have the correct trap parts & installed correctly?

A return line blockage is not impossible but unlikely.

You say it is a vacuum system. With the trap opened up and the vac pump on you should be pullin air through the return.

jc2lite1

I replaced with what Barnes and Jones said it replaces an 02H trap with, 1972 cage unit. You mentioned vacuum pump on, I don't know what or where the pump is. Is it internal?

jc2lite1

Just did another test without the cage unit and it is hot.

109A_5

Hello jc2lite1,

Another trap could have failed open air locking the cold radiator.

Paul S_3

This sounds like an old vapor vacuum system that's no longer going into vacuum with an automatic fuel. I could be wrong though. Is steam coming from the supply or return? Is this an ongoing problem or fairly new? 1972 cage unit is the correct cage unit for the warren webster 02H traps. Are you using a new cap or the original. Those cage units require a new cap, unless the cap was replaced in the past with that cage unit

jc2lite1

Coming through supply. Barnes says you can use existing cap. Just noticed this this season.

Jamie Hall

I think that what I read up there is that when you took the internals out of the trap, put the cover back on, and turned on the steam the radiator got steam. But that when the internals are in the trap the radiator does not get steam.

Is that correct? If so, then its the trap internals.

If you get steam with the trap cover off but not with it on, there may be something — such as a water trap —blocking the return.

jc2lite1

Jamie Hall, It is strange. I noticed it when heat was on and it was cold and took out the original cage unit. It got heat. I put a new to me off ebay cage unit and it did not heat. I took the cover back and I could the steam moving so I took out the unit and put the cover back on and it worked. The next morning it was cold. took cover off and had steam instantly at the supply valve. Now today, it worked without the cage unit and without removing the cover. I just replaced the cage unit and will see what happens.

Jamie Hall

eBay strikes again…

jc2lite1

So I swapped out the cage unit from the defective radiator and put it in another and it is working fine. The radiator that is not working gets heat without the cage unit but doesn't retain it of course. Could it be the return line is somewhat plugged under the floor?

Jamie Hall

It could. Though if the trap is working properly I'd expect it to work anyway. You could try pouring water in copious quantities — don't be shy — into the trap housing (take the cover off an have at it). It should drain freely and completely. Don't forget to check the boiler water level afterwards!

109A_5

Can you pour water through the return side ? Sagged pipe in the return, trapping water ? With the system running and the cap off the trap and the radiator side of the trap plugged with a rag does anything come out of the return side ?

jc2lite1

Just poured a half pitcher of water in and went right down. Blocked off the the radiator with a rag and nothing coming from return. But also no steam going to the radiator with the cap off now. I'm stumped!!

109A_5

" Blocked off the the radiator with a rag and nothing coming from return. But also no steam going to the radiator with the cap off now. "

With the rag blocking the radiator port the steam won't enter the radiator since it can't push the air out, as expected. With the return port able to vent to the room let it run for a while or recover from a slight setback and see if anything comes out. If absolutely nothing comes out there is probably water blocking the return pipe due to poor pipe slope. I would expect air to come out, or eventually may be even steam if there is a stuck open trap elsewhere. Maybe temporally block off the main vent (with tape) to force the the air out of the open trap.

jc2lite1

Woke up this morning and it is hot. Still no cage unit in it.

109A_5

Interesting… The trap should only close the valve with the presence of steam, maybe poring the water in moved along some obstruction.

mattmia2

The gurgling when you ran the system sounds like water trapped in the return somewhere so that radiator can't vent but the water got sucked out for whatever reason with the return being open to atmosphere with the system running.

Also possible that steam is in the returns from bad traps elsewhere in the system and is keeping the air from being able to vent. Steam could also get in to the returns from a water seal that isn't below the water line or isn't far enough below the water line.

jc2lite1

The gurgling is coming from the radiator. The supply line to the radiator heats up almost immediately.