Mains pressure vs pumped shower

Basically, we can't answer your question unless you do manage to measure your static pressure and potential flow rates. (You need both to be reasonable).

You might have some idea at the kitchen tap. If you turn on the cold and it blasts out, then you should get a good shower.

To measure flow rate and pressure without proper equipment:

Flow rate: Fill a known size bucket at the kitchen tap. Time how long it takes to fill and calculate the litres/min. If your kitchen tap is a modern type (especially the hose type), the potential flow rate may be considerably greater than that measured. Try the garden tap, if you have one.

Pressure: Stick your thumb over a tap outlet as hard as possible. Open the tap a little (even a tiny amount is OK, and will result in less spray). If you can stop the water coming out with your thumb, you probably have under 1 bar static pressure and you should consider not fitting a mains pressure solution.

Christian.

Few mains pipes will not improve on that 1.4 bar. Go mains pressure and the problems of a pump disappears.

On Mon, 07 Aug 2006 12:27:59 GMT someone who may be "Jim" wrote this:-

So far so good.

What advantages do you think this will bring, compared to your current type of system, or a thermal store?

Mains pressure "instant" hot water systems have their advantages in some situations, but that is a different discussion.

As you can't tell us the mains pressure, anyone who provides firms answers is a fool or a liar. What criteria are you interested in?

What do you want out of the system? How many outlets? What sort of outlets? What is the likely demand pattern? How quick a recovery do you want? Have you considered a venturi shower?

Thanks for the input so far, got a bit more info....

Flow rate - would appear to be 20l/min

Pressure - using the garden tap (which has a short length of hose on it) I can't stop the flow by using my thumb over the end. ie the water forces it's way out

Reasons for system -

Need to replace and relocate the current 30 year old boiler up to the loft The HW tank has packed up so also has to be replaced Have 1 bath, 1 pumped shower and 1 sink upstairs, 1 shower, 2 sinks downstairs There's 2 1/2 of us in the house and can forsee both showers being used at once in near future Ideally would love a shower that flays you alive - this is nowhere near what we've got at present but as long the replacement isn't anything less I'll be happy Hopefully should get HW at the taps quicker than the 30secs + we have to wait now By not having a cold water and F&E tank we would free up a lot of loft space we cannot currently get access to

Basically we've gone for the system as suggested by our plumber. It was the most expensive quote we got from 3 different plumbers (all suggested a different system) but think it will suit us best

Thanks for any further input you can give

Jim

Buy this for £12. It connects to the washing machine or garden tap connection.

Depending on the mains pressure the shower could smack you against the wall.

You can improve the cold water flowrate by installing a an accumulator. This gives pressure to what the static pressure is at the mains, but way more than 20 litres/min.

Or it might just be worse. The statutory minimum is 1 bar and plenty round London are close to that.

But presumably your high rise council flat has its own header tank?

Is that how they do it on your sink estate?

No sink estates round here. We sent all of you to MK years ago.

And remember that a pumped system wont scald you and then go freezing cold every time someone flushes the toilet, runs the kitchen tap or puts the washing machine on.

dg

No s*it!

What do you refer to?

Exactly. As I said we exported it to MK.

So the alarm bells should be ringing for any combi system.

MBQ

He said system boiler and mains pressure HW tank, not a COMBI.

To OP. Do it. Its infinitely better than a pump.

I never want to go back..from mains pressure plumbing and a huge pressurised tank.

He isn't using a combi.

The van lost its way as they put them all back in Sarf Lhandan. Appalling place,

I would go for a heat bank and abandon the unvnetd cypdiner. They have an annual service for the cylinder of £60-£100. and can do this:

Do it with a mains pressure heat bank. If your plumber doesn't understand these get back to me.

Oops!