Electric water feeder overfilling

mel rowe

Would greatly appreciate any suggestions as to what to check and fix on a McDonnell Miller water feeder, model no.WFE.  Thought the problem was with the water level probe, but replaced it and water feeder 3Gstill over fills.

Charlie from wmass

you may be shooting the messenger

Mel the feeder is often the thing doing its job. Check near boiler piping, venting, and check the returns for clogging.

nicholas bonham-carter

auto-fill equals over-fill?

if you can turn off the water line leading into the auto-fill, will you see an alarming drop in the water level, over a period of days? does the solenoid valve close completely?

i had a "mysterious migration of water", when we first installed our new 1,050,000 BTU peerless. that temporary shortage of water would have caused an "over-fill" condition, if i had put an auto-fill on. since i have never trusted them, i did not, and the system [55 rads] is all gravity.

my return piping hid the water in long horizontal runs, as pressure rose in the boiler; and then came back during the off time. after we reworked the dry/wet return transition, the problem disappeared. i also  put in a "reservoir tank", which takes care of the time lag between first firing and condensate return.--nbc

Al Letellier_21

over-filling boiler

On the other hand, if you shut off the water to the feeder and it still overfills, it could be from another source, like a leaking tankless coil....???

mel rowe

Electric water feeder overfilling

When I shut off feed line, the water level dropped very slowly and the the low level probe activated after about 8 days.  Near boiler piping is good.  Venting is good.  Just spent most of two days  skimming and cleaning entire system. Only thing I can think of is that as suggested, the solenoid is not closing completely. Can the solenoid be readily removed and cleaned? 

mel rowe

Solenoid valve cleaning?

Just looking for comments.

nicholas bonham-carter

testing the solenoid

now that you have had the feed water line shut off, and turned back on, the only way to test the solenoid, is to cut the power to the feeder. if after that, you have an overfill, then the valve must not be closing.--nbc

mel rowe

NBC and solenoid valve

NBC, I tried your suggestion to deactivate the valve, with the water turned on to the feeder.  Sure enough after a couple of hours, the water level on the sight glass went up by about 1/2 in.  I took the solenoid valve apart and found a lot of crud in the valve seat area.  Cleaned out and assembled and found no leakage afterward, in a short time.  Will monitor closely to see if it continues to operate okay.  Thanks very much.