Radiator only heat 1/4 of radiator Steam

shaohui456

Just ask for some brainstorming and help. It’s a two pipe steam system. 

The radiator is not heating up. It’s located in the top of building. It has suction from the return. The radiator only hot on first 4fin. It’s hot but not like burning hot. The temperature that you can grab it. The 5th fin is ice cold. 

I did the necessary step of taking apart the steam trap, and two plug to see wether steam will come out. Not thing came out. 

Other apartment has heat. The apartment right below has heat. The other steam radiator in opposite side of apartment has heat. 

I am thinking about more pressure and balancing related problem. 

The house is under renovation for 3 year due to Covid. No idea what’s before that, but the building said they got heat before. 

It shouldn’t be back peach issue because it’s not back peach. 

They did recently replace the new cast iron radiator but I don’t think it got anything to do with steam transfer. 

Thanks in advance for answer and help. 

mattmia2

What kind of valve is that? It looks like some sort of metering valve that gets set to match the amount of steam the radiator can condense.

JUGHNE

Is the large supply steam pipe hot....burn your hand hot....just before the valve?

And writing or numbers on the valve, clear close up picture of valve may help.

shaohui456

It’s not burning hot, it’s little hotter than warm. I find out it work on one day, the day after didn’t hot again.

Long Beach Ed

What kind of valve is that? It looks like some sort of metering valve that gets set to match the amount of steam the radiator can condense.