Hot water taps cease to flow after 10 seconds or so.

[Tweed]

I had to drain the plumbing system (cistern only but I think this syphoned half the cylinder?). Now after refilling the system the hot water taps flow for about 5 - 10 seconds before stopping. It seems unlikely it's an airlock. Has anyone any ideas on what's the problem

[Tweed]

Actually, come to think of it, the cylinder could have some air in it. That would explain the gurgling sound just before the water makes its brief appearance. What do you think?

[AlBags]

What type of system?
Combi?
Direct pressurised?
What cistern did you drain exactly? You mean a header tank?

[Tweed]

Plumbing system (indirect) not heating. The cistern in question is the main cold water storage tank in the loft.

[mr_doubtfire]

It does sound as though you have an air lock. Chances are that somewhere in your hot water pipe system you have an inverted "U" shape, probably to get over an obstacle and that's where the air's caught, my brother had the same problem. What we did was make up a short length of garden hose with a tap connector on each end, we connected them to both the hot and cold water taps on the bath, opened the hot tap slightly and then opened the cold tap. We gradually turned them on and the pressure in the cold forced the air lock back up and out of the hot into the header tank, you could literally hear it gurgling in the bathroom!! Might work for you.

[Tweed]

Hi mr_doubtfire. The problem has resolved itself now but I was still curious as to what the problem was and your explaination seems about right. I was going to use mains pressure up the hot tap to cure the air lock - if it came to it. Thanks for your answer.