will my shower stil be good

[dmm27]

Hi
We are having an extension built that will mean replacing the current boiler and cylinder, but I am concerned that the showers we will get will not be as good as our existing one.

Currently we have a gas boiler with vented cylinder. We have a 1 bar booster pump (from Wickes) to supply the shower, that puts out 20-25l/min at the shower head. Its a really nice shower, and we would be reluctant to get less than this on the new system. (the pump used to empty the header tank before I enlarged the hole in the filler valve for the header tank!)

The new system will be an unvented system, sited on first floor. We have been told that Mira and Aqualisa showers are probably the best for flow etc, but cant really find out what sort of flow we can expect. I have yet to find a shower as good as our existing one in other peoples houses. The extension will give us 3 showers, but realistically only 2 will be in use at any 1 time.

The water board have tested the mains pressure and we have 5 bar, 25l/min flow. We will probably replace the supply pipe from mains to stopcock as we currently have either lead or steel (certainly wont be plastic). We will also need new pipework fitted throughout inside.

Are we likely to still get a decent shower flow rate? What sort of shower makes would you recommend, and is there anything else we should watch out for?

Thanks

 

[ChrisR]

Everything has to be right to get high flows. Sounds like you're doing the right thing with the pipes, and 5 bar is good.
But an typical Unvented cylinder (kit) will reduce that to 3bar. If you put a standard Grohe wall mixer and its standard head on it you'll get about 17l/minute, though it will feel more, because the water jets will be coming out at higher speed.
An electric shower is a measly 4l/min, but feels ok because the holes are small so the water is fast.
Some mixers are very restrictive. You have to check with manufacturers, though their information can be alarmingly limited.
A thermal store or Heat Bank would allow you to keep your 5 bar, without the reduction. See http://www.heatweb.com/