Air locks

[RodH]

I have a traditional hot water system with hot tank. Over the last few days it has developed continuous air locks in the hot water system. Turning on the taps and it gurgles/slows down/stops/starts again etc.

I have tried flushing out the system by attaching the mains supply to the hot tap and pushing back up into the cold tank and out the overflo. Left it for an hour doing this, turned on the hot tap and a few seconds again it started again. There must be air coming into the system. Any ideas?

Thanks

Rod

 

[algas]

Check that your ballvalve is filling correctly, if not the tank may be emptying & sucking in air before the incoming mains can fill it.

 

[RodH]

Yep, there's no problem there. Now I do have a pump to the shower, and it's not connected by a surrey flange, and I've had it for three years without any trouble, however the problem exists when the pump is not working, and it's only gravity supplying water to taps

 

[seco services]

you could have a restriction in the top of the cylinder outlet pipe restricting flow from cylinder then drawing in air from the vent pipe.
or a restriction around the gate valve on the supply to the cylinder restricting the filling of the cylinder.
ie loft lagging etc.

 

[RodH]

Problem solved. Air was being sucked into the cylinder from the vent pipe. When I had tried to flush the system by putting mains water through the hot tap that didn't cure the blockage as the water came out via the vent pipe, following the route of least resistance. Blocking off the end of the vent pipe meant the water had to go through the blocked area, and it blew the pipe clean

Thanks for your help

 

[seco services]

trouble is what ever was blocking the pipe that you have now blown back into the cylinder is more likely to be drawn back to the outlet pipe at sometime unless removed.