Trickling sound (HW)

[BiFF]

Hi All,

Hope somebody can help I have a vented HW system with a pressurised Ch system but got bit of a annoying issue, when the hot water comes on all seems ok then after about 15/20 mins i started to hear a trickling noise from hw cylinder which i can also hear in the boiler. The central heating system is fine no noise, The noise only accurs when its on hot water only, if i turn the CH along with the HW on the noise goes away. The central heating pump was recently changed. The system has been cleaned and new inhibator, water in the system is clean. I have bled the pump and also the vent in airing cupboard. Could this be a faulty 3 port valve?> water in and out the tank in loft seems ok, going up and down as expected.

 

[Ben-gee]

Probably air in the coil or the pipework feeding it.
If you bleed this the noise should stop.

 

[Chuck]

Check that it's not coming from the tundish, which monitors the water discharged from the cylinder in the event of over pressure.

 

[Chuck]

Check that it's not coming from the tundish, which monitors the water discharged from the cylinder in the event of over pressure.

Forget this, it only applies to unvented systems. (I didn't read the OP carefully enough.)