Steam Boiler Overfilling

Larry C_13

If all three boilers have hot water coils, I would ask the water company if they have been flushing mains, having water main pressure surges, or using new water chemistry.

Larry C

cable 21

Steam Boilers overfilling

Im a Plumber for 20+ years and have had three steam boilers lately that are overfilling into the steam header and need to be drained every two to three days. Two of the boilers have 1/2" ballvaves on the feed and one has a MM water feeder. Cut into feed pipes below ballvalves to check for ballvalve failure dripping and in all three cases saw none. Have known customers for years and all three say no makeup water was added by them. Any ideas? thanks

Unknown

all three boilers?

All three boilers on the same job site?

cable 21

No three different houses.

billtwocase

overfilling

I may be proven wrong, only have a hand full of steamers, but if there is auto feed, have seen surging work the float to feed water in whether it needed it or not. Also dirty sight glass so customer guesses what the water level actually is. Not sure this helps, but only 2 ways water can get in, unless there is an indirect with a leaky coil, or a tankless with a pinhole. peace

RJ_4

If autofilled

I have seen some boilers overfill if the M-M SA101-- fill valve strainer or entire valve is plugged up. The strainer is removeable. Also the fill line may be plugged where it ties into boiler return line. In both cases the automatic fill valve sees a big pressure drop holding the valve disc off the seat, overfilling the boiler. In most cases this happens over a long period of time. Check condition of low-water cutoff if it has not been serviced in years, you may want to replace it. Also check 1/2 or 3/4 inch line at return piping.

clammy

things to check

Cable 21 are you sure that your pressuretroll is set at a cut out of 1 .5 psi ,if your sressuretroll is set above 2 psi you may be taking on water durning a call for heat being the ondensate must stack up to gravity bak to the boiler ,lower your pressuretrol and check your wet returns if you have them ,they may be clogged and be slow to return condensate back to the boiler and the feeder is just doing it job to maintain it mimiun water level peace and good luck clammy