CH pipes creaking for hours after heating turned off. Any ideas?

[Josh95]

Hi, recently moved into my first house and am fairly new to DIY.

I've been experiencing issues with banging and creaking central heating pipes since I moved in. I've now lagged and secured piping wherever I can access it which has fixed the issue to some degree however fitted wardrobes are causing complications with access in certain areas.

Now I understand that it's normal for pipes to expand and contract when heating and cooling however my pipes seem to creak even hours after the heating has been turned off. I've bled the radiators and can't seem to get any air out of them. Any ideas what could cause this at a point where the pipes should effectively be cool?

Thanks

Josh

 

[Chuck]

Any ideas what could cause this at a point where the pipes should effectively be cool?

The cool pipes will be left in tension. The stick-slip release of this tension can take hours before everything stabilises.

The ideal solution is to design pipework that accommodates the expansion and contraction, e.g. dog-legs or corners, and mount pipes so that they don't rest directly on woodwork but have a pad, traditionally hemp lagging, that allows them to slide without sticking.

If you secured pipework without allowing for some sliding you may make matters worse, or you may get lucky.

 

[Josh95]

Thanks for your response. It does see like I've traded the banging/clicking noises for this long running creaking! Heatings been off about 8 hours and I'm still hearing it intermittently.

I did secure a long straight run of 3 22mm copper pipe using felt lagging on the notches on the joists along with some styrofoam tubing on the middle pipe to stop them from touching eachother and the floorboards above. I did have to stand on the floorboards to compress the foam down enough to screw the boards in so the pipes are effectively wedged between felt and foam (no clips used). I guess maybe the foam has put downwards tension on the pipes?

 

[ShaunCorbs]

I would remove the foam and just just felt lagging