open vented system unexplained noise

[martineire]

Well i went into next door to have a look at a problem they suddenly got and i cant find the problem. there is a noise coming from there rads when the heating is off, it sounds like a pumping sound or the rads filling like sound. I checked the feed/expansion tank is full in the attic, i bleed the rads down stairs and they are all full, boiler is turned off and i checked central heeting pump was not running. But i cant understand where this sound is coming from even with boiler turned off. She said when i was leaving she has underfloor heating just in the bathroom down stairs and there is a room stat on the wall just outside the bathroom that she says its just for the underfoor heating in the bathroom. (its the only roomstat in the house). So im thinking now could this problem be a fault with the pump on the manafold for the underfloor for the bathroom that its constantly running (when heating is off) and the sound is coming back through the system.

 

[bengasman]

For starters, it is a wonky installation; ufh must always have a separate roomstat and timer.

 

[martineire]

The UFH does have a sperate digital room stat/timer on the wall outside the bathroom door. Is my theory of the fault possible?

 

[bengasman]

The UFH does have a sperate digital room stat/timer on the wall outside the bathroom door. Is my theory of the fault possible?

Separate as in: 1 for ufh, 1 for ch

 

[martineire]

Central heating side has a mechanical time clock.

 

[bengasman]

Not quite the same as a roomstat, is it?