New shower, cold water brilliant, hot water dribbles out shower head. Do I need a single pump or a booster pump. Many thanks Nigel

new shower, cold water brilliant, hot water dribbles out shower head. Do i need a single pump or a booster pump. Many thanks Nigel

Hi Nigel and Welcome to The Plumbing Page. At AskMeHelpDesk.com.
No pump needed here, What you have is minerals built up in the pipe wall that's broke loose and is now clogging the hot water inlet port of the cartridge. The solution would be to shut the water off to the valve and open it up. Remove the cartridge and check and clean out any trash you find. Now turn the hot water back on to flush out the supply. Reassemble and test. Better now? Good luck, Tom

Thanks Tom, may be I didn't explain myself properly . All new pipes, I think its all to do with gravity, just not enough pressure, The hot water tank is lower than the shower head.? Cold water is fine.
Many Thanks

Thanks Tom, may be I didn't explain myself properly . All new pipes, I think its all to do with gravity, just not enough pressure, The hot water tank is lower than the shower head.? Cold water is fine.
Many Thanks

Hey Sam.
Your entire house has been Repiped?

I think its all to do with gravity, just not enough pressure, The hot water tank is lower than the shower head. Good thinking but just not correct. ALL waters are lower then the shower head. The house water pressure is what moves the water up hill. The first thing I would do is shut the water off to the valve and open it up. Remove the cartridge and check the inlet ports for trash and blockage, Now turn the water back on to flush out the supplies. You should have a strong stream from the supplies as you do this. Reassemble and test, Better pressure now? Good luck, Tom