radiators noise, "poping/snaping noise"

Hollis

Not sure anything can be done about this, but is there anything to reduce the snapping sounds of radiators? Sometimes pretty loud. I'm guessing its he joints of them esp near the top(?) Wondering if a bit of silicone liquid on the joints would help? any ideas? This is not steam hammer because of things like radiators not tipped back or from the boiler problems. it happens with hot water systems as well.

nicholas bonham-carter

What sort of radiator? Pictures would help.
Are you thinking expansion/contraction noises? Maybe the inlet and outlet pipes are rubbing against the wood.
Does this take place constantly, or just during recovery from a setback? If so, then a constant (lower) temperature setting may reduce the sudden heating up of water during recovery. Outdoor reset might further improve the constancy of loop temperature.--NBC

Hollis

I don't know how to send pictures but this is general question to a lot of old radiators in a number of houses (landlord) No pretty sure its not pipes against the wood, i have dealt with that before in a few cases. These sound like a small hammer that sharply hits the metal. Yes it does happen esp this time of year with our local weather not currently being very cold and a lot of time between cycles...currently dealing witha two pipe steam system,..not sure how to slow the heating rate to the radiators.

Jamie Hall

It's not the radiator joints, or at least I hope not -- they should be really solid. What has often found to be very helpful -- assuming that the pipes are free to move -- is to be sure that the feet of the radiators are free to move. I suggest a small easy sliding pad under each foot -- and being cheap, I suggest cutting a pad from a plastic milk jug and slipping it under each foot. It's worth the try...

Rarely, some radiators have tension rods near the top and the bottom (actually, a lot of radiators do). If those are a little loose, they can make a noise. However... be very careful with them. It is tempting to try to tighten them, but it is very easy to break them. If the nuts don't turn reasonably freely, don't keep trying. They'll snap, and that's a bore. But a bit of silicone on them might help.

vaporvac

I think it's just general expansion/contraction noises as mentioned above. Only a more constant heat will avoid them. I'll often get a small "clang" when the system starts to cool. It's very random. try using a lower, but steady temp and see if that helps.

JUGHNE

I hear the "clinks" at my church as it comes out of a cold setback. These are steam only rads, only connected across the bottom. The top has floating interlocking tabs which I attribute to the clink/pinging. these are pretty tall rads and I'm assuming that each section expands at the top and hits its neighbor. There is one rad that has too long of a run out and will definitely have water hammer....sounds very different.

My knees and ankles make this noise also.

FranklinD

Oh yes, mine make this noise as well. I have an old converted gravity system. It happens specifically on 2 radiators, both the largest (longest) in the house.

If the boiler runs a cycle, as the radiators cool down after awhile, I can reach behind my chair and push firmly on the radiator and I get the 'PING'. Only once. It won't do it again until the next cycle.

The kitchen radiator is the other...it can be made to ping by walking across the floor with firm steps. Again, once per cycle.

They've always done it. The pipes don't have any hangers in the basement below, and they're both about 8 feet from the mains. The only common factor is that both have several 90's where the risers come through the floor. Thus, my theory:

With every cycle the long runouts lengthen and shorten, and build up tension in the 90's to the radiator until the thread 'pops' very slightly (just enough to make the noise). Like a swing joint with super old, dry threads.

To me, it sounds like a very quick, half-hearted rap on the pipe under the radiator with a small ball-peen hammer.

The radiators with short or straight-run pipes don't make the noise at all. I've come to actually like the noise...one of the many our home makes.