Hot Water Pressure upstairs

Jag1978

Hi All

Just a quick question…. Just moved into my new house… Noticed that the hot water pressure upstairs is pathetic. The cold seem much better… What could be the reason for this. I’m assuming the boiler is about 5ish years old - (Valliant)
It’s weird as the mixer bath tap with attached showerhead doesn’t seem to be able to push the water to the shower head when you pull the changeover thingy!! Obviously this isn’t normal as my under standing is that the hot water pressure should be similar to the cold.
What could be causing the problem?

Regards

Jag

moonrakerz

Assuming yours is a conventional hot tank/cold tank system.

Your cold supply pressure will be from the mains. Your hot water supply pressure will depend on the height of the cold water header tank in your loft.
To boost the hot water pressure you will either need a pump or raise the cold water tank in the loft on some sort of platform.

Jag1978

Sorry should have made myself a bit more clearer, it's a Valliant Combi Boiler, so no header tank!

Jag

ukwoody

I'm nnot a plumber so Canknucklehead and the others may say I'm wrong, but the cold will come straight off the mains, hence the better pressure. The hot will go via the combi which will be govened in a couple of different ways. Now lets say the water pressure isnt very good, it could be that it's enough to run the boiler and system, but by the time it has gone thru the boiler (instant restriction), gone upstairs, and then to a shower head (which may have a bigger feed pipe, thus again reducing pressure) it will have basically run out of pressure. Boilers have Flow rates (lets say for example 15 litres per minute), if it is a low value boiler with a low flow rate as well, you dont stand a chance in hell.

There may well be a flow rate setting on the boiler which will allow a greater flow - but reduce the overall hot water temp. By changing this, you will get the shower to work, but it may not be very warm.

Hope I've made this clear.

I'm sure one of the boys will be along shortly and know that boiler well and can confirm or deny my comments.

woody