Low hot water pressure, only upstairs..

Idonex

Hi,

Our water has been fine until this morning. Went to have a shower and there was not hot water coming out at all. The hot tap in the bathroom is barely more than a dribble, but something does come out. The cold taps seem fine, and the hot and cold taps downstairs are also fine. The heating also seems to be fine.

We only have a combi boiler with no tank. The pressure on the boiler is normal (at about 1.5), there are no errors on the diagnostic display and all the temp displays look normal. The only thing i've noticed is a slight knock, or bang from the boiler when i turn the hot water tap back to the off position.

This was fine last night, so not sure what could be causing this? Any idea if there's anything else i can check before i have to call someone in?

Thanks

macman

Sounds like an airlock if you have adequate hot water downstairs?

evoke

Could be an airlock. I would also check the filters in the bathroom basin and shower. Perhaps some dirt in the pipes was dislodged and is blocking the filters? Undo the nozzle (assuming you have one) at the end of the spout on the tap in the bathroom and see if it is clogged up - you may need an adjustable wrench but do it gently!

The filters on the shower might be more tricky as these could be in the valves rather than the showerhead.

Anyway, an article on removing an airlock is here: http://articles.cleverdodo.co.uk/fixing-a-blocked-water-pipe-caused-by-trapped-air/6

Idonex

Typical sods law it seemed to be back to normal a few hours later. Then we lost all pressure again. So I tried all the airlock tricks anyway and it didn't make any difference. Then it went back to normal again....and now it's gone back to almost no hot water coming out of the taps upstairs, and now i'm also pretty sure the pressure on the cold water tap upstairs is a bit lower too. The downstairs taps seem fine still. I rang Thames Water and there are no reported works or incidents near me.

So, our plumber came round to take a look. He said he can't see anything obviously wrong with the boiler, the inlet taps in the cellar and kitchen look ok and he can't see / hear any obvious leaks. He did do a flow test on the cold water feed from the kitchen tap and outside tap and he said they were only running at 5 litres a minute which is way too low, but to be honest the taps in the kitchen seem as fast as they ever were.

Not sure where else to turn. Is it worth ringing Thames Water and reporting our cold water mains pressure is very low (although i doubt its ever been much better than it is now downstairs and everything upstairs worked ok before)

Thanks

evoke

Get a proper plumber in! A good plumber should be able to identify the problem.

keystone

Airlocks in a mains pressure system? Even if the pressure is a little lower than normal how can that be?

Cheers