Rushing/bubbling sound of water in pipes - boiler/pump off??

[bodram]

This is a good un...
I have an indirect hot water system and this has worked fine for years - no work on the whole system for several months. Tonight the pipes in the general area of the hot water tank sound like they have boiling/rushing water in them - this has been going on for 5 hours.

I don't think it's boiler related as the boiler went off 3 hours ago as did both hot water and heating pumps - so don't think it's a pump bearing.

There's no air in the central heating as all radiators are getting hot(tried bleeding all radiators and got water but no air) and the hot water taps all run freely (no spluttering etc.)

Checked hot water expansion tank in the loft and this has about 4 inches of water in it (although going by the tide mark this looks to be about 2 inches lower than normal) - by the way there's nothing coming out of the vent pipe into the expansion tank.

Just ran ALL of the hot water out of the tank and the noise is still there.

Now that there's no hot water and the radiators have cooled I'm starting to think that the noise sounds like running water in the pipes but all taps are off and I've checked all overflow pipes, also checked drains for sound of run-off but all looks good.

Turned off the water at the mains and the noise goes on.

So - in a nutshell - everything seems to be working OK but we have this non-stop sound of rushing/bubbling/boiling water in the pipes?

And now I'm out of ideas??

 

[Slugbabydotcom]

Turn your main stoptap off and see if the noise stops
Then try doing the same with the electrics to your heating system
What about your immersion heater? Is that turned on?

After that contact Most haunted on Living TV and they will check your house out for paranormal activity

 

[bodram]

By the cold light of day I can see we have a mains leak out in the road - I guess there's air getting in. Never heard such a racket.

Turning the mains off in the house didn't help, I'll try turning the mains off at the valve outside the house now.

Just got to wait 5 bloody days for Thames Water to fix the leak now!

Great forum, good to know help is at hand.

Thanks.