Hot water flowrate upstairs is zero?

[MarkHan]

Hi,

I wonder if anyone can help me diagnose a problem that has just developed this morning. My upstairs bathroom hot water flow has reduced to virtually zero, while the cold water mains is also reduced but still workable downstairs.

I have a gravity fed system, where the cold water loft tank feeds both the downstairs hot water cylinder and the upstairs cold water taps in the bathroom(which again are working but at a reduced flowrate). The downstairs hot water taps are operating at a reduced flow rate but still working.

We have rung the water board who will come and check the incoming mains pressure on Thursday. What confuses me is that I thought that the incoming cold mains shouldn't effect hot water pressure from a system like mine i.e. All our hot water pressure is created by the loft tank height.
So, short of just running out of water I thought our hot water pressure should be unaffected by the incoming mains?

Is this right or is there some indirect way the hot water pressure might be effected by a reduced mains pressure i.e. cylinder tank not filling quickly enough?

Any comments would be welcome.

Thanks.

 

[oilman]

.....hot water pressure should be unaffected by the incoming mains?

You are right. Look for a blockage, like a rodent in the cold water storage tank stuck partly in the outlet pipe. (Ugh!)

 

[djbunny]

possible air lock, you need to disconect washer machine pipes (turn water off first) the connect hot to cold using one of the hoses, then open both wm taps up and run for thirty secs turn off then check tap upstairs, repeat if nesacery.

 

[MarkHan]

Thanks for both replies, much appreciated.

I've checked for a blockage at the water tank end and everything looks OK (as much as I can make out).

djbunny, Is the idea of connecting the washing machine hot and cold together, to push the air pocket out of the system using the mains pressure? I'll try that tonight.

Thanks again.

 

[djbunny]

yes

 

[MarkHan]

Thanks for all the replies.

Particularly djbunny, your solution worked a treat.

Cheers.