Hot & cold pressure differences

[badbob]

Had a Wochester 530i combi condensor boiler fitted. The pressure on the kitchen hot tap is ok- and upstairs (in fact probably too much as it just blasts out, don't have enough control to do a trickle- but the taps are quite old and have just bought whole new tap suite) but upstairs it takes a while filling the bath up. The amount of water coming out from the hot tap is a bit lower than it was with the hot cylinder system. The dial on the boiler is hovering at 1, sometimes dips under sometimes over. The boiler is on the ground floor, and the bathroom is on the 1st floor. Hot water cylinder was on the 1st floor.

Would a hot water pump help things? I'll be looking into a thermostatic shower, so would a pump before the bath tap & shower increase the pressure, or can only the boiler output hot water at the amount of hot water it can produce on demand?

 

[Winston]

You cant put a pump on a combi mate

 

[GreenArmy]

Get used to the hot water flow mate it wont get any better. If you are fitting a thermostatic mixer shower off a combi boiler you will get a brilliant shower.
Your combi boiler is supplied with 15mm mains pressured cold water which will heat as it passes through the boiler and although its mains pressure it comes out slower as it needs to heat as it flows through boiler.

 

[badbob]

Nothing I can do then? I could increase the tap water temp, which means I'll have to mix in more cold water to bring it to safe level- and it'll probably mean setting the safety lock out on my taps as too scolding, but it's annoying the two are so wide apart.

 

[Winston]

The hot for the bath is in 22mm isnt it?

 

[badbob]

You mean from the boiler to the bathroom? I don't know. They did not put in new piping to the bathroom even though I told them we're getting thermostatic shower, and I did ask them would new pipes to the bath be required? The bath taps are about 25 years old.

It takes 30 seconds to fill 12 liters from cold, 1:15 from hot taps.

Just taken the bath side panel off and they do appear thicker than the central heating and hot water pipes for basins.

 

[heinz57]

Do you have isolation valves on the bath pipework? if so make sure they are full flow valves. Also, if you have flexi connectors going from the copper pipe work to the taps then these can cause problems and also be restrictive but you can get full bore flexi's. If you are in a hard water area you may have scale build up in the hot pipework (ive even found bits of mdpe pipe causing partial blockages). Failing all that you could try reseating the taps and checking for restrictions there.
Also, if there is an iso valve make sure it's fully open. Good luck!

 

[stevetheplumber]

first thing to do is look at the lterature that came with the boiler and see what the flow rate for the hot water should be ive looked at the site for worcester and cant find a 530i listed ? if its the 550 it should supply 24 litres