Low Water Pressure

[viking]

Got a Worcester 28i combi boiler brand new running sound , upstairs the bath room pressure is fine for the shower but the bath takes 1/2 an hour to run it is slow as hell , anyone got any suggestions?

 

[breezer]

see how long it takes to fill a bucket to a 1 gallon mark, try it on shower, bath, sink downstairs.

if all take the same time or a close you have low pressure it may be cured by changing your incoming water supply pipe but try the test first

 

[viking]

Ive done the test, down stairs fills slightly quicker, the pressure is that low that when I turn on the taps upstairs and down the ones up stairs stop, dry! any solutions that aint gona cost me a re-mortgage??

 

[oilman]

Sounds like they both have the same pressure available, and the problem may be the mains supply. Do the same test again with the cold water tap nearest to the place the supply comes into the building, and please post the times for the tests, "slightly quicker" does not say much.

 

[viking]

Thanks for the reply, tap nearest the mains is the kitchen and it takes 29 seconds to fill to the 1 gallon mark!

 

[ChrisR]

That's reasonable, unless it drops a lot if you turn on another mains water tap.
Now measure the hot flow at the bath - expect no more than about 9 litres a minute for bath temperature water.

Of course you can't have 2 hot taps working toghether. It's a combi!

 

[viking]

The bath runs at 46 seconds for a gallon from the hot tap!

 

[oilman]

Hmmm, that's about 6 litres a minute. What does your handbook say about required flow and pressure?

I have checked my tap and it delivers a gallon in about 12 seconds. Thats better than 20 litres a minute, and I've restricted the flow. You may have a water pressure problem. Can you measure it? If not, you need to find out what it is so you can work out where the fault is.