What The Heck Is Going On?

CluelessBobinBrookyn

I am a homeowner who is not mechanically inclined in any way. Last summer I had a new gas steam boiler installed in my home when the old oil-fired one developed a leak above the waterline. We managed to limp through the winter by constantly patching any holes through which the steam escaped with a high temp form of Mighty Putty. (I had just had our huge oil tank filled when the boiler sprang a leak and I wasn't going to waste all that expensive oil.) This year we have had nothing but trouble with the new boiler. Heat was very uneven throughout the house. Boiler was recently skimmed by the plumber. I changed all the air vents on the radiators and installed a new main vent. The old main vent was a Dole #1933 and the new one is a Gorton #1. After changing all the vents all the rads got hot, but I had a very loud bang in the basement wall. I don't know , but I think it may have come from maybe a return pipe from one of the basement rads? (Can't tell because basement is finished.) Scared the hell out of the wife and kids (me too) and was so strong that the boiler hit pressure and shut down. Now when boiler starts there's a lot of strong banging coming from the boiler itself and banging in the pipes in the basement. I don't know exactly where the pipes run in the basement because it is finished, but it seems that the banging is coming from toward the back of the house now as opposed to closer to the front when the really big bang happened. Water in the sight glass is clean on bottom but the top is caked with dark brown rusty colored sludge or slime which makes it hard to determine water level in boiler. Could the pipes and/or the boiler be full of this stuff? Is there any danger in running the boiler this way? What should I do? I have one pipe steam and the near boiler piping and the mains have been insulated as per Dan's instructions in his book. Main is approximately 2 inch pipe and about 57 feet long. Called the plumber and he said there's dirt in boiler from the pipes and I should clean it. (He said he was busy with other no heat. calls and would get to me when he could.) How do I clean boiler and pipes? Please help because wife and kids are afraid to stay in house. Banging starts inside boiler near top of boiler in a few minutes of starting up. Thanks.

BobC

Questions

As noisy as this new boiler is right now all steam boilers have safety's on them that keep pressure from going too high so everybody should be safe.



On the front of the boiler there is a pressure gauge, what does that read when the boiler is producing steam?



Is the water level in the sight glass bouncing up and down a lot?



What kind of boiler did he install? Is this single pipe steam?



Did he replace any of the return piping going to the boiler? Find the installation manual and compare the piping diagram in it to what the boiler looks like now. Does anything look different from that diagram?



Does your boiler have a float type low water cut off? Did the plumber show you how to clean it?



Please post pictures of the boiler from different angles showing the piping around it. We need to see it all so stand back a little bit. If we need any close ups, we'll ask.



Bob

Jamie Hall

Safe enough...

it's probably safe enough; the lovely percussion section you have is almost certainly water hammer -- which can be remarkably loud.  And which, in this case, I would be very much inclined to attribute to problems in the new boiler install.  What causes it is water getting into the steam mains, being pushed along at a good clip by the steam, and hitting fittings.  Won't break anything, except your sleep.



However.  It does sound as though the boiler install may have left something to be desired.  Can you take pictures of the new boiler and all the piping in its immediate vicinity and post them here, so we can take a quick look at them?  That would be most helpful.  We may be able to figure out what went wrong, and tell you how it should be fixed.



In the meantime, your description of the sight tube on the boiler suggests also that the boiler was probably not skimmed or cleaned when it was installed.  They have to be.  Get you plumber to come back and do that and do it right.  There is dirt in the boiler, but not from the pipes, and it has to be cleaned out.  Not the pipes; they're probably fine (particularly since this problem began after the new install, eh?).  The boiler.



That main vent is probably not big enough, but we'll worry about that later.



Get us some pictures!

crash2009

I can give you some help cleaning it.

Get me a couple photo's so I can point to things you need to open and close.

Getting Steamed

Are you sure?

Ae you sure that it's water hammer? The banging sounds like it's coming from inside the boiler, or in the pipes closest to the boiler (header and risers, Hartford loop). Is it still okay to run?

Rod

Water Hammer

Hi- Dirty boiler water produces "wet steam" and "wet steam" causes steam to condense ("collapse").  When steam "collapses", One cubic foot of steam instantly changes to one cubic inch of water. This produces an instant void/vacuum and the surrounding water rushes in from both sides of the void to fill the vacuum. When the water from both sides of void collide this produces the noise we call "water  hammer".   This is the noise you are probably hearing and it can be quite loud! Here is a link to a good video on showing steam collapsing and water hammer which might help explain the noise to the wife and kids.

http://www.kirsner.org/pages/WaterCannonVideo.html



Draining the boiler and filling with new water and then skimming will get rid of the "wet Steam" (and the noise).

You might want to post some pictures of your boiler (and the near boiler piping)  as sometimes if the piping isn't configured properly this also can produce water hammer.

if you need draining /skimming instructions let us know.

- Rod

Jamie Hall

No, I'm not. I can't be.

I'm not there.  But I'd be mightily surprised if it were anything else.  If the boiler water is grubby enough (see Rod's post below) you will have wet steam with a vengeance, and could have severe cavitation in the boiler itself -- which won't hurt much except your nerves.  You will also have wet steam in the header, even if it is piped correctly.  Ditto.  And you will also have wet steam and water in all the rest of the basement pipes, which will produce genuine water hammer (slug of water being rammed into a fitting at about a hundred miles per hour).  Which can make an equally horrible racket.



None of this will do short term damage; none of this means its unsafe to operate your boiler (if you can stand the racket).  All of this means, at the very least, that that boiler needs to be skimmed and, quite probably, drained and refilled and skimmed again until it is clean.  It probably means that you have near boiler piping problems as well, but that we can't tell until we see some pictures.



It can be aggravated by trying to run at too high a pressure, as well.  (anything over 2 pounds is definetly too high).

jpf321

waterline considered?

what was the Height of the Waterline of the OLD boiler and what is the height of the new boiler? Has it changed (lowered) from the old boiler?



If it has lowered, you may have horizontal pipes (hidden away in your finished walls) that perhaps used to be underwater but are now "dry" .. rather than rip open your walls, perhaps you can ask about the installation of a false-water-line which will put those pipes back underwater ("wet") ..



this is only a possibility if your water line is lower with the new boiler than it was with the old .. What was the brand/model of your OLD unit? What is your current unit? We will look it up for you.



Making previously wet horizontal returns dry could certainly cause significant banging.