Pressure valve question

LEADPIPE

My daughter live in an apartment in NYC. She sent me a video her radiator. Every day when the heat come on she gets steam popping out of this valve, only lasts a minute or so. Is this a normal situation? She notified the landlord but I would like more information about it. 

Thanks!

LEADPIPE

Sorry, lasts about 30 minutes. 

Jamie Hall

That thing is actually called a vent, not pressure valve, and its job is to let air out of the radiator when the steam is trying to come in. It should close when steam hits it. If it lets steam out, it may be partly failed, or weak -- but if it stops after a bit it may be doing the best it can.

It is likely that the steam pressure in the building is way too high -- very common in apartment buildings in New York -- and over the years we've kind of found that it's pretty hopeless to get the landlords to turn it down to where it should be...