Steam system knocking

Cyclist

Help- I have a new Slantfin gas fired steam boiler that also has one zone of hot water baseboard in addition to the single pipe steam radiators. My system is knocking loudly. This boiler replaced a burnham that had a hot water coil that was used to provide the hot water zone. Now, the hot water comes directly off the slantfin boiler without a coil. I have an automatic low water feed. Slowly, I see the water rise to the top of the glass tube over a week after water has been drained off. Once the water level rises all the way up the kicking starts. It goes away when we drain more water off, but starts again as the water level rises again. We delayed the auto feed so water gets back to he boiler before it adds, but the knocking still comes and the water level still rises.

Other than another boiler with a coil for he hot water zone, can anyone think of a fix for this problem?

bob young

Steam system knocking

SOUNDS LIKE IT NEEDS SKIMMING  TO START WITH. ALSO EXAMINATION OF HEADER PIPING ETC.

Rod

System Problems.

Hi- Post some pictures of your boiler from different angles so we can see how the piping in connected to it. Take the pictures a ways back from the boiler the pictures include the boiler and the piping. If we need detail we can then zoom in.

- Rod

STEAM DOCTOR

loop

Is the hot water loop above or below the water line of the boiler

Cyclist

Steam system knocking

Thanks for everyone's replies and interest.  Here are some pictures.

I'm a consumer, so I'm relating what I've learned through trying to get this fixed.  I think my contractor is a good one, but I thought we should look for more input.  It's getting expensive.

Yes, the boiler has been skimmed more than once.  As well as drained and refilled.  The water looks clean as of the last draining.

Take a look at pics, but I think the water zone is below the water level in boiler.

Repiping has been discussed.  We have added an additional timer to the auto feed, so that the feed is delayed 8 minutes, hoping that the water from water zone plus the condensate from steam pipes has all returned to the boiler before the auto feed kicks into action, which we think has been over filling.  But, since this was done we had only ten days without knocking, and now we are knocking again, though not all the time.

We are trying to do this without huge expense.

Thanks again.

bob young

Steam system knocking

Supply to aux. baseboard system looks too high. general piping arrangment looks sophmoric. should be ripped out & redone. with all due respect.... a real homeowner diy mess.

Cyclist

Steam system knocking

Thanks for input. 

Is it possible the lowering the water zone could fix this?  Or is repiping probably the thing to do?  Or is it simply possible that the water zone should be on a coil, or completely separate from the steam boiler?

The system was installed by someone who never finished, and has disappeared.  Current contractor has mentioned wanting to repipe, but is trying to spare me the expense.