Sudden widespread water hammer

redhaven

I have owned my house a little over a year so I had a partial heating season here last year and I am hopefully just a few weeks away from the end of this one. I have gotten some good advice about improving my system in the steam section and I read "we got steam heat" but my problem is more immediate (I have been up almost all night!) so I thought I would post here. When the water hammer started, i had made no changes to my system at all.

After working fine if not great for the entire time I have lived here, I suddenly have what I think it system wide water hammer and it is really bad, enough to wake me up (it is 4am here). I read through the list of causes and solutions for water hammer on this site but I can't tell if my problem fits.

I first noticed the water hammer 2 days ago. After reading through the list from this site, I thought maybe the water was dirty so I emptied some out and replaced it. I added more than I wanted because I was having a hard time seeing the level in the glass and I kept adding and removing water until I finally got it right but by then the water coming out was lukewarm where it has been near boiling. Oddly enough, after replacing that water, the hammer went away for the next 12 hours or so but then it came back.

Here are some factors and symptoms I am noticing.

I think it is happening more at the start of the cycle
I noticed that the radiator in my upstairs room is not heating up (it has always worked) but the pipe that is feeding it on the floor below is hot and making a bunch of noise
I hear a lot of gurgling and water flowing through that pipe and I think in the system in general
It seems like the boiler is starting and stopping more than usual. It has always run for a little while,then shut off for a few minutes, and then started back up but it seems like it is happening more now. It is really cold here and it is working hard.
Other than the one bad radiator, the rest of the house is heating up normally after a few minutes of hammering..
My pipes on the main floors have no insulation. I am going to insulate them and I know this can be a cause of water hammer but it doesn't seem like that could be the problem because I have never had water hammer before.
The water I removed from the system was really dirty with lots of debris and I suspect that the system is really dirty. The boiler is only 4 years old but the pipes and radiators are original (which I know from another thread that the system is not piped correctly but it has been working pretty well).
It is crazy cold here in Eastern PA and has been for days so the system has been running a lot, even when my kids and I aren't home.

I had read in the list of problems and solutions that the pH level of the water can be a factor but I do not know how I could add vinegar. The water fill pipe is clamped onto the boiler so I don't think there is a place to add anything without removing the clamp.

Sorry for the long explanation but I wanted to give as much information as possible.

Red

nicholas bonham-carter

Something has changed recently with the boiler to start the water hammer, and the job is to return it to normal operation.
Let's start with the basics:
1. Check the pressuretrol, and its pigtail for obstructions which could prevent the pressuretrol from seeing the pressure and allowing the pressure to get too high. Check the pressuretrol settings and make them as low as possible, verified with a good low pressure (0-3 psi) gauge.
2. This boiler probably needs to be skimmed, when the weather is warmer, but for the moment, a drain and refill several times will be better than nothing.
post some pictures of your boiler and its piping for more advice.--NBC

redhaven

I can't edit the original post but I just noticed that the radiator in the upstairs bedroom did get hot. It must just have taken longer.

redhaven

Thanks for your response. I checked the pressuretrol and it is set to 1psi. I didn't open it up because I wasn't sure if it was safe after the boiler just cycled. When I ran the system, the pressure gauge looked like it was reading around 1 psi but I don't think it was designed for this type of system because it is marked off in sections of 5 psi so 1 barely registers.

I think I discovered the problem. The boiler had too much water in it. There is something wrong with the water level gauge glass. I removed a bunch of water but the water level did not go down in the glass at all. I dropped it all the way down until the low water cutoff engaged and the light came on which meant removing a significant amount of water. I'm not sure how much but I would say at least 7-8 gallons. Then I added enough water to turn off the low water light, fired up the boiler, and it is working fine with no water hammer as I write this.

It explains why this all happened in the first place. I probably went down there and even though the low water light wasn't on and the reading on the glass was ok, I probably added a little to top it off before I went to work because nobody was going to be home. I am not sure when it started but I may have done it many times without realizing it. Duh.

So, any idea why the gauge glass might be broken? There are two knobs on the top and bottom. I have a probe type low water cut off.

redhaven

Ok problem completely solved. Some idiot that looks a lot like me had tightened down the knob that allows the free flow of water to the gauge glass. Then he proceeded to put too much water in the boiler. I will make sure that he keeps his hands in his pockets from this point forward.

A moderator can close his thread. Thank you for your help.

BobC

We've all done something like that at one point or another.This is saying I had posted over my calibration bench a few decades back -


ACHTUNG!

ALLES TURISTEN UND NONTEKNISCHEN LOOKENPEEPERS!
DAS KOMPUTERMASCHINE IST NICHT FÜR DER GEFINGERPOKEN UND MITTENGRABEN! ODERWISE IST EASY TO SCHNAPPEN DER SPRINGENWERK, BLOWENFUSEN UND POPPENCORKEN MIT SPITZENSPARKEN.
IST NICHT FÜR GEWERKEN BEI DUMMKOPFEN. DER RUBBERNECKEN SIGHTSEEREN KEEPEN DAS COTTONPICKEN HÄNDER IN DAS POCKETS MUSS.
ZO RELAXEN UND WATSCHEN DER BLINKENLICHTEN.