Hot Water Tank Noise??

[2ede3]

Over recent weeks i have heard noise like rumbling then bubbling, that seems to be coming from the tank in my loft. I assume it happens through the day also, but is drowned out by everyday noise, but at night this is very loud and can last from a few to maybe 30 seconds or more. It is very frightning, knowing you have hot aswell as cold water above you, and not knowing the cause. This noise still happens even when the boiler is switched to off position during the night. It is not happening on a daily basis but maybe once a week at present that i know of.
Any advice would be much appreciated, as i am very concerned about this noise.

Thankyou in advance.

 

[Bahco]

Go into the loft and ask someone to turn the taps on while you listen.

It could be the ball valve opening and closing.

 

[2ede3]

As the water is run from any tap in the house, the tank empties and fills as normal making no sound out of the ordinary.
The noise is definately coming from above, and what is strange is this noise that sounds like a rumble then bubbling or kettle boiling, is happening with the boiler shut off and when all the hot water is used and running cold.
I think this may be one to get checked out.
Thanks.

 

[kevplumb]

are you sure the immersion heater isnt on

 

[2ede3]

No the boiler is switched to the off position, my heating is cold and the hot water is now running cold. Honestly when this noise happens for those few seconds it is very loud, could maybe sound like a plane flying by, that sort of roaring/rumbling followed by bubbling. There are some occasions when you hear noise very briefly and this too is a very slight rumble. I do admit it does seem to happen more if the water in the tank is still hot but has happened when boiler has been shut down and water is just luke warm. These noises also only seem to occur when there is no water activity such as water being run or toilet flushed etc, it is mainly during the night which makes it even more strange.
Thankyou.