I have a single storey cottage and consequentially have very little head to drive a shower. There's an extension that has the shower in it, currently electric.
I'm having PV panels fitted so it seems sensible to use the excess electricity to heat the tank for a 'proper' shower.
The shower is some 8m from the tank with a 15mm HW feed for the a basin in the shower room and the kitchen. If that pipe is pumped, and including the shower, will that pipe be bigger enough?
Thanks in advance Rob
I'm not sure about the concept of "excess" with FIT payments, but I don't think you need to worry about using any excess locally, you get paid regardless. How's your HW heated at the moment?
I would have thought that 15mm would be fine with a pump. Increasing the size will just increase the "dead space" and resulting more wasted water whilst waiting for the hot water to arrive.
Tim
Since it will be sharing the load with the cold pipe, it should be ample unless you are planning a very "thirsty" shower.
=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D= =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D\
=A0 =A0 =A0 =A0|
=A0 =A0 =A0 =A0|
=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D= =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D/
Thanks guys
Winter HW is heated by the oil CH system and a wood burner; in the summer it is electricity. My intention is to re-direct the 'export' PV power to the immersion heater then - there's a device called an Immersun (=A3400) that can be relatively easily reproduced for =A320 of components.
The secondary question is related to running the kitchen tap off this feed too - will the modern shower thermostat cope with change in HW pressure ?
Rob
We were all prepared to change a couple of ancient Mira shower valves when we got our mains pressure HW tank but they've coped fine. I would have thought a more modern thermostatic mixer wouldn't have a problem.
When we had a pump, we used it to boost the whole house HW supply with no problems.
Tim
In article , robgraham writes
Not really, there will be a time delay until the capsule reacts to the change in temperature and corrects it so you will get a cold blast at turning on the kitchen tap and a hot blast when it goes off again. There are more expensive mixers that balance pressure too but a separate pressure equalising valve might be a better (cheaper and longer lasting) choice:
Use it on the hot and cold feeds to the shower (only). If pressure drops on either feed then the other will be dropped to balance it, resulting in an overall reduction in flow at the shower but not (hopefully) an imbalance in the flow or change in temperature.
Thanks guys - your help is much appreciated.
Fred - the pressure balancing device; if the pump is giving say 2 bar and the mains 4, I take it don't need to go for a double pump for the shower, but would it be necessary to pressure reduce the mains ?. Very desirable to go for a single pump as additional pipe would be tiresome to fit.
Another question having read the DIY WIKI/FAQ. Pump position problem. How much flexibility do I have on how far below the HW tank head the pump has to be ? One option is 600mm, though with the bottom of the tank effectively just to the right above my head here at the keyboard (the top of the tank is just above the attic floor), I've seen another possibility on the floor of the cupboard immediately above my desk. So actually the question still stands in that it would be better not to have it on that floor, but on the back wall of the cupboard. Hope that is understandable!!
Rob
Same here, I was expecting to need to change an Aqulisa power shower (its internal pump has been seized for all the time we have owned it - but it worked as an adequate thermostatic mixer on a low pressure feed). However I shoved 3.5bar up its chuff and so far it seems to be working fine!
If you added a PRV to the mains, then that also isolates the shower a little from pressure drops caused by demands on the cold made elsewhere in the house. (dishwashers / WM etc seem to be the worst culprits for demanding bursts of full flow cold)
There is no particular requirement for it to be below the Hot tank - the main thing is that is is well below the cold one. (and the shower needs to be below the cold cistern as well to avoid needing a negative head pump)
Its quite common to have the pump on the same base as the hot water cylinder. The pump specs will specify the minimum head required. So long as you can meet that, then the relative position of the hot cylinder is less important.
In article , robgraham writes
In that situation there is no need for a cold side pump but the valve will reduce the pressure of the cold feed to the shower to mach that of the other feed. If the pump is giving 2 bar and teh mains is 4 then the cold outlet pressure will be reduced to 2 bar as well, giving you a balanced feed. If someone draws cold off elsewhere then the valve will maintain 2 bar on both until the cold inlet pressure drops below 2 bar, at which point the pressure on the hot side outlet will be reduced to balance the reduced cold pressure. If the hot pumped pressure fluctuates due to demand, the cold will be reduced further to compensate and maintain the balance.
Separating this function off from the shower valve lets you use cheaper mixers. My pending shower refurb here will use simple bar type mixers that are easier to replace when they (inevitably) go wrong.
Not my area, sorry.
Thanks John and Fred - not one of tomorrow's task but should be sometime in the next year, particularly as you have now sorted a couple of problems for me.
Rob
HomeOwnersHub website is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.