Steam radiators vents squirt water everywhere

Dave_122

A recent replacement of the boilers in a school now has the radiators vents squirt water everywhere. It is a one-pipe system that allegedly ran fine after the 1st boiler was replace, one not now after the 2nd boiler was replaced. Today it was discovered that a steam line PRV was added after the headered boiler supply piping connection to the building. I am of the opinion that this is a big mistake. The PRV is set at 2-psig and the boilers cut-in at 1.5-psig and cut-out at 5-psig. Some has decided to raise the steam cutout pressure higher. Another mistake in my mind. Please help with suggestions of what to do to help the school with this problem. Thanks in advance.

JUGHNE

Round up all the usual suspects:
Pressure too high
Lack of steam main venting
Wet steam caused by dirty boiler or bad boiler piping.

Are there two boilers on line?

Pictures are always welcome.

Dave_122

I believe both boilers are online although I don't know how they are controlled for lead/lag. Possibly just the pressuretrol settings

What do I look for when I am looking for steam main venting devices?

Thanks,

Dave_122

Also, what about the use of a PRV for the system?

JUGHNE

Steam main air vents are usually screwed onto the top of the pipe at the end of the steam main before it drops to a (usually smaller) return pipe going back to the boiler or a pump receiver.

There may be other components in the system that require the higher pressure for higher temps. Perhaps a hot water heat exchanger providing domestic hot water or hot water to a reheat coil on an air handler.....perhaps for fresh air brought into the school.

Pictures in the boiler room may explain much.
A couple shots of radiators showing both ends also.

Jamie Hall

PRVs can be used... but... if the system is intended for heating only (no high pressure uses) it's much better not. If they are used, provision for handling condensate downstream of the valve must be provided -- because there will be a good deal of it on saturated steam. If this is heating only, there is no reason at all to have the cuout pressure higher than 2 psi.

Dave_122

Thank you.