I had a leaking isolator valve that is connected to my bath hot water tap, so I decided to change it. I turned-off the cold water mains and opened the hot water taps in the bathroom and kitchen to drain the system. I have the cold water tanks in the loft and the hot water cylinder in the bathroom. I changed the isolator valve without problem, but now I just have a trickle of hot water coming through the kitchen and bathroom taps. If you keep turning the taps on and off you get a surge of water and a lot of spluttering. The cold water pressure at the taps is fine. Is this an air lock and how do I sort it? I would be grateful for any advise. Thanks.

It sounds very much like an air lock, how long have you left the hot taps open for?

I left the taps on for about 2 hours without success. Thanks.

Are there any other hot water taps that are working?

If not is the mains water feed to the hot water tank OK?

The mains feed to the hot water cylinder appears to be fine. I only have the 2 hot water taps that are both just trickling out water. Someone has recommended for me to disconnect my washing machine feed pipes and join them together. Then, use the mains pressure to push the air lock back through the hot water system. I will give this a go tonight. Thanks.