Hot water pressure low

[bladerunner]

Hi, Hope someone can help here goes, I have just installed a whirlpool jacuzzi bath with a mixer hand held shower attachment all connections are half inch. The problem is the pipe to the hot water is 22mm so I have made this down to a 15mm and 15mm isolation valve connected to 15mm flexi hose connected to the half inch tap, the cold water is fine through the tap and the shower but the hot water pressure is very low on both the shower and the tap. I then connected the 22mm pipe to a 22mm flexi hose with 22mm isolation valve and made this down to 15mm with a 15mm flexi hose to the half inch tap, still no hot water pressure, please any advice on what is the solution to this problem. Cant understand why the bath taps are only half inch either unless this is a foreign bath.

 

[Mike Jackson]

Check the specs on the bath it may require high pressure. The flexis you are using will reduce flow rates through their smaller bore. If you must use flexis get the largest bore possible but it's preferable to use rigid pipework to minimise losses.

Mike

 

[plumbnuts]

What type of hot/cold water system do you have. It is most likely that you have gravity hot water. If the taps are 1/2" inlet, they are normally only suited for high pressure systems such as combination boilers or unvented.
Steve

 

[bladerunner]

Hi, I have an ideal classic boiler I think it"s a combination boiler fitted 8 years ago in a newly built house, perhaps you will be able to determine what hot/cold water system this is with my description of the boiler.

 

[Mike Jackson]

The ideal classic is a heat only boiler. They did make an ideal classic combi which was a classic with a combi module bolted onto it but I thought this was more than 8 years ago.

Do you have any form of cylinder?

Mike

 

[bladerunner]

Yes I have a hot water cylinder in the airing cuboard, to reply to your previous post the specs say requires a balanced water supply of between 1+3 bar to achieve this pressure you may require an equalising valve or a pump, how do I find out what my water pressure measures and do you think a valve or a pump will solve the problem as I cannot fit rigid pipework as the panels on the bath are not removeable to do this all the pipework is at the rear of the bath and has to be turned on its side to connect everything and then gently lowered into place. Hope this all makes sense to you.

 

[Mike Jackson]

If you can take a picture of the cylinder that will help us ascertain what type of system you've got. It may be a thermal store which gives mains pressure hot water but I'm inclined to think it's a standard system due to the problems you are having.

Do you have any tanks in the loft? If yes how many and what sizes?

Mike

 

[bladerunner]

Sorry cant take photo of cylinder as my cameras playing up but it is the hot water cylinder if thats any help. I have two tanks in the loft one has the writing on POLYTANK FEED SYSTEM 39X20X21. The other tank is smaller with a ball cock in it.

 

[buffy27]

u need to get sorted out with a pump in the hot press,is this feasible.

 

[bladerunner]

If a pump is the only solution then thats what I shall get, but can you tell me why the hot pipe to the orginal bath tap is a 22mm and reduced to a 15mm about 2inch from the top of the pipe to fit on to a 3/4 tap when all my other hot water pipes to the taps are 15mm and the flow seems to be ok, and would reducing the 22mm to a 15mm lose pressure on the hot water. Which pump would be best and where would I get one.