banging pipes

ekodish

I will try to lower the pressure tonight and see what happens. The pipes bang the whole time the circulator is on. So this could very well be it. On the gauge the high point is marked at 60psi so I thought 50 was ok.

will let you know monday.
two story house. 3000 square feet with two zones. Boiler in basement.

ekodish

banging pipes

just read your article about banging zone valves. I am not sure if this matches my problem. I have a two zone forced hotwater heating system. With baseboard pipes with fins,no bleed valves.

When the heat kicks on then there is banging . All times of the night, banging, knocking, banging knocking. It seems to change locations all the time. Certain noises from certain parts of the house. When i hear the knocking I often jump out of bed and look at the feed pipes to see if they are moving around but they aren't. I do this because we recently installed hardwood flooring and thought the pipes might be too close to the flooring. However I can't see them moving around.

Any suggestions would be helpful. This is happening even when i have the downstairs zone off. I tried to bleed the system last night. on the return there is a hose hookup and I let out a lot of water. The autofill seemed to kick on and the boiler maintained 50lbs of pressure and would then bring the temp up to 160-190.

thanks,
eric

Earthfire

how many stories

on your building? 50 psi on a residential boiler is little high

bigugh_4

27#'s

pressure should do it! (for 5> 12 foot stories) or lower it till you can just get water out of the highest radiation. Has a new circulator been recently installed? if so, It could have been to much of a pump for the system. Water velocities above 5 feet per second tend to cause water hammer. An other thing is piping mounted to tightly against wood. Pipe will expand when heated, and if it slides just right against anything it can and will knock, bang, or creek. Paper, soap, graphite lubrication (Non-staining) or just looseining a hanger or support can quite the noise.

ekodish

We bought the house in april. And although we had quite a few cold nights we didn't have nearly this much of a problem. The house is 12 years old so i assume original circulation motor/boiler/everything.
Right now the noise is mainly upstairs. I have downstairs set very low at 65 and upstairs at 72. I don't really hear downstairs making any noise. The noise on the second story seems to be close to baseboards but always seems to be in the wall. When i hear the noise I run over and look and even try to shake the pipes to see if i can reproduce the sound but It doesn't match. I would hate to have to tear up flooring and walls.

What pressure would you recommend.

ekodish

mistake

oops. PSI is about 22. I was looking at the altitude.

Any other suggestions. Noise is still driving me nuts and it all seems to be in pipes hidden in the walls/floor.