Heating Technician

Rach

Steam heat system is making a loud banging noise it is a vacum vapor system with 2 motorized steam valves. Banging seems to be worse when steam valves are closing note this is a residential application. Boiler is 400,000 BTUs operating on a vapor stat with a receiver tank returns are high and dry



I've checked the vacum vapor vents returns and traps they are ok



should I remove vacum vents and leave the system on vapor?

Jamie Hall

Are those

valves dripped on both sides to the wet returns?  If not, they'll be trouble -- and may be your only trouble.  Taking the vacuum feature off the vents won't help the banging.