wrote in message
oups.com...
I am currently renting an apartment with steam one pipe radiators.
When the heat is on in my bedroom, it causes the windows to fog to a
point where they are dripping, creating pools of water on the sills and
optimum conditions for mildew to grow.

Obviously steam is escaping, and I have realized that it is through the
air vent. I understand that the air vent should close when the steam
hits it, but clearly this is not, as on close inspection while it was
on I found there to be steam rapidly escaping from the vent. So my
question is, should the vent be cleaned, or should I contact my
building manager to get a replacement? Or is there another answer
entirely? My building manager isn't great at understanding a problem
when you talk to her (language barrier), so I would prefer to use
specific language that she can tell the maintenance man, rather than
broad, "it's not working", especially if it's something easy to fix.

Thanks in advance, I've seen you guys give some great advice.

Yes, you could have a faulty PSV (Pressure Sensitive Valve). Close the
valves to the radiator and wait till the rad cools...Then replace the PSV.
These DO leak after years of service and is cause by scale build up,
weakening springs etc.. Make sure you replace the valve with the same
pressure rating... Jimi