Plumbing Question

I have recently experience a serious drop in hot water pressure, one day it was fine the next it was as follows :it starts ok when the tap is turned on but soon drops to a dribble.the water is hot

Gravity fed system cold water tank in the loft seperate cylinder in the airing cupboard

managed to sort the issue on a short term by putting the mains via hosepipe up the hot trap,however the problem reared its ugly head after 1 bath full of water .

The does seem to be alot of miscellaneos debis in the main cold water tank so I clean that out and see what happens however this doesn't seem to affect the cold water supply/pressure upstairs

many thanks for the help


8 Answers

Best Answer

it sounds as if you have already cleared any chance of air lock already by running mains preasure water up the hot water pipe so it sounds as if what you have is debris in the pipe. you cleared trhis temporarily by running mains preasure up the pipe but the debris came back down again blocking your water flow. find out if blockage is pre cylinder or post cylinder and treat to clear accordingly.

Answered 5th Jun 2011

kevin cassidy building contractors

Member since 16 Dec 2010

Sounds To me that you have got an air lock can be removed by back filling hot from cold main as it is of a greater pressure and will push the air lock back out.
If Prob persists after running bath sounds like your storage tank in loft is running out and drawing air in quicker than is filling back up try changing ball valve to see if this helps you can put a Larger ball valve in, this sometimes will do the trick.
Garry D&G Builders

Answered 4th Jun 2011

D&G Builders

Member since 10 May 2011

Sounds like you have an air lock try blowing into your tap. Failing that you need a plumber to try a few other tricks.

Answered 4th Jun 2011

JWC Property Services

Member since 25 May 2011

you have a airlock,or possibly some blockage

Answered 4th Jun 2011

AGplumbing heating

Member since 17 Jun 2008

sounds like an air lock which is common on gravity systems,its easily fixed
Gregg Russell

Answered 4th Jun 2011

GR Plumbing and Heating

Member since 14 Sep 2009

seems like you have got an air lock

Answered 4th Jun 2011


Member since 5 Oct 2007

Have you checked that nothing has fallen into the cold water tank in the loft?

Answered 4th Jun 2011


Member since 22 Dec 2008

Sounds like a tycipcal air lock in your pipe!
Has any one been up in the loft just befor it started playing up?Thay may have nocked a pipe and changed it out of its rising direction?
If not has the header /storage tank got lids on them??
could be that something has dropped into the tank and is restricting the water into the feed pipe.

regards Ashley

Answered 4th Jun 2011


Member since 3 Mar 2009

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