weil mclain steam boiler banging

norb

I recently had a new Weil Mclain steam boiler installed. At first it worked fine. On day five banging. The plumber came
back and did a skim thru the relief valve with some tool he has ( i was not there) and he added a chemical. All was fine that day. Now, for the last three days the banging is there again, hissing in the radiator vents, the furnace kicks on and off too quickly at times, and no consistent heat to some of the radiators. I called him to come back and install a skim port. I recently watched two videos by Gerry Gill. The first one on skimming, the other on washing a boiler.
My question is, rather than do a washing, will a few good skimmings solve my problems?

Abracadabra

A good skimming is required. A good skimming takes time.

What pressure is the boiler hitting?

norb

The needle does not move from zero

KC_Jones

You mention he added chemicals. Chemicals can not replace a good skimming. Skimming takes time, think in hours as many as 8-12 hours total depending on the amount of new piping. If that is a Weil Mclain EG style boiler a proper skim can not be done through the relief valve it just won't work. The skim port is a 1 1/2" connection on the side of those boilers. Get the proper skim port installed. I agree with above...what pressure is it set for? If it's surging (meaning it needs a good skim) that can cause short cycling because of the pressure fluctuations, but could also be due to too much pressure and inadequate venting. There are many factors, but the skimming really is the first most critical step. Once it's skimmed and running smoothly then you can determine if there are any other issues.

Abracadabra

Get a lower pressure gauge on there. I assume you have a 0-30 PSI gauge.

norb

ok--thanks guys