Pump or heatbank

[robgraham]

Firstly many thanks to all those who have patiently answered my queries on heatbanks. If I go this way, there will no doubt be one or two more but for the moment I now need to consider my other option and that is using a pump to raise the DHW pressure.

The problem is that my house is a long cottage (originally two) with an extension - it's a T with a short leg ! The extension has the kitchen and shower at the outer end of it where the riser is. The shower (electric) and the kitchen sink are fed off the riser as it does it's 15m+ run to the CW tank.

There are two complaints from the household - the shower is poor in the winter, and the hot water feed to the kitchen tap is pathetic, the latter caused by SWMBO having me fit one of those mixer tap that is on the end of a shower hose - great if you have at least 2bar pressure but useless when it is in the order of 0.6bar.

One option is to supply local HW to the shower and kitchen to eliminate the something like 10m feed from the HW tank, but that I think would be expensive to run (electric heating) and would still need a pump.

Anyway that's an aside -

1 can one pump supply two separate needs is the initial question.

2 where does the pump go ? The top of the HW tank is level with the attic floor.

3 Can I feed mains water into one side of a shower mixer tap and pumped HW into the other?

The rest of the plumbing is traditional - CW tank, vented indirect HW tank, oil fired CH system.

Thanks

Rob

[John Stumbles]

If you did the heatbank thing you could have a small local PHE+pump+flow switch arrangement local to those draw-offs.

generally yes: some pumps are specified for multiple outlet applications like this whereas with some you'll invalidate the manufacturer's warranty even if it's not precisely aligned with a ley line :-) But pumps are cheap enough ...

As low as possible, and tapped off the DHW as low as possible (or, by the book, with a separate tap off the cylinder e.g. essex or warix(?) flange)

You can. I wouldn't like to try to get a good shower from one if it's a manual valves. Some of the bar-type mixer valves are very tolerant of different pressures.

If you're only using the pump to boost the hot water then you *should* use a single-ended shower pump but since double-ended ones are cheaper you might want to simply parallel up the ends to do HW only. The Salamander one from Screwfix at about £100 is good.

[David Hansen]

On 22 Mar 2007 02:33:26 -0700 someone who may be "robgraham" wrote this:-

What electrical rating is the shower?

What is the water pressure there and how does it fluctuate.

An electric under-sink heater would be the thing, if the pressure is adequate. However, even a 9kW one is not going to fill a large kitchen sink rapidly.