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Moving house shortly to a place with a bath, but no shower. There's space for a curved corner unit, but it's level with the hot water tank, so expect pressure to be poor.
In our current place I fitted a 2 bar boost pump, and that has been fab... but the plumbing set up was very conventional and the fit was straightforward (gas boiler, hot tank in airing cupboard, cold water header in loft)
House we are moving to is old and has some very idiosyncratic plumbing, so I'm trying to work out what's suitable in showerpumpworld.
- Two hot water cylinders, plumbed in series and heated by oil fired cooker.
- Cold water tank in loft, but only as a header tank for the hot water system.
- All cold water taps (bathroom, kitchen, outdoors) all running direct from mains supply - and therefore at mains pressure...!
Do I just need a single impeller pump to boost the hot, or would a twin impeller be better so that hot and cold are regulated to the same pressure - and if so, is it ok to connect the cold supply direct to the pump from one of the mains pressure cold pipes, or do I need to run a new cold feed from the loft header tank???
Why not just fit a power shower?
Combi Boiler? Although it sounds like potentially not on gas network?
Every power shower I've tried has been disappointing... 🙁
i.e. isn't the "power" element based on electric water heating rather than on pump assisted shower pressure???
Also, the oil fired cooker is constantly providing water heating (hence twin hot tanks), so it would be mad to use electricity to hear more water from cold...
ETA - FunkyDunc, correct - several miles from nearest gas main
Power shower = a pump forcing the water from water tank though the shower at higher pressure.
Personally I don't like them as they are noisy.
However if you are constantly heating hot water then would appear to be the best route to go down.
If plumbing from new potentially could put the pump out of the way some where?
Power shower = a pump forcing the water from water tank though the shower at higher pressure.
That's not what I understand by a power shower, and a quick google returns what I thought they were... but naming aside...
A cold water mains shower that has a heating element in it. No messing around with boilers and header tanks and no noisy pumps.
Not sure on the dissapointment side, but every gravity/boiler fed shower I've used has been crap. But that could just be the ones I've used (crappy old ones in crappy old houses).
A cold water mains shower that has a heating element in it.
You need a lot of power to heat cold water in winter to a decent temp and get a good flow...
Either combi boiler or pumped showed off HW tank.
You can get Venturi induction pump showers, which use CW pressure to suck HW out (of a tank) - no electrics, no pump needed, and work fine if you have good mains pressure.
If you decide to go for two HW cylinders plumbed in tandem, why not get a simple evacuated tube solar panel to pre-heat the water in the first cylinder? I did this a few years ago and it works fine. The kit cost about £700 including the 160 litre cylinder I bought off Ebay and it was an enjoyable little DIY project.
Look at: http://www.solarproject.co.uk/
You need a lot of power to heat cold water in winter to a decent temp and get a good flow...
The pipes are buried deep enough that the temperature is constant. Hard to imagine cold water temperature changes by more than a degree or two.
Start from scratch and put an unvented mains-pressure system in then you will get mains pressure hot water on, er, tap.
+1 for mains pressure unvented hot water tank.
I fitted an 11kW electric shower in my flat before ripping out the heating and going for a large combi. Was a lot better than 9kW one. You will need the electrics running off it's own RCD/RCBO supply though so I would just improve all your hot water with a mains pressure tank. If your existing one is old and not very well insulated then you may well save money on oil too.
Mains water temperature definitely isn't constant here. The non-thermostatic electric shower I use is set to 8 in the depths of winter but it's at 4 now.
I found this, from a company in Scotland, which suggests it can vary between 4 and 20 degrees (20 seems an awful lot; maybe that's the bit that has sat in domestic pipework for a bit?)
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Some useful responses, thanks.
I don't want to be too drastic with changing the existing setup - too integral to the house fabric. So the oil fired HW heating and twin tank system needs to stay in use...
On that basis, presumably no point using a pump on the cold supply as mains pressure sufficient? Just a single impeller positive head pump for the hot water feed?
The pipes are buried deep enough that the temperature is constant. Hard to imagine cold water temperature changes by more than a degree or two.
Notice a big difference at home (Cambridge) and in the cottage (Swaledale), in the latter the electric shower is useless in winter, just runs at a trickle. I turn the HW tank thermostat down by 10C in the summer at home as the power shower mixes less HW in to maintain the output temp.
BTW - there are rules regarding pumping mains water:
Water Regulations state that you can pump from the mains so long as there are safeguards in place so that 12l/min is not exceeded. As always, check with your local water authority.
5thElefant - MemberThe pipes are buried deep enough that the temperature is constant. Hard to imagine cold water temperature changes by more than a degree or two.
Nah, the output (in terms of water volume) of our 10.5KW electric shower varies massively between hot weather (a couple of weeks ago) and the depths of winter because all you're doing is controlling the flow rate to give the water passing through the shower more or less time to heat up.
In the hot weather, we've had the dial turned all the way to cold & it's still been too hot when you want a cool shower. I've been using the econ setting, which cuts one heating element off.
In the depths of winter, we might have the dial turned to 2/3 of the way towards hot, which gives a decent temperature but at a lot lower flow rate because the incoming water is a lot colder.
Having said that - our shower is perfectly decent any time of year. Even when we have to run it at it's 'slowest' in winter, it is still far from being a trickle.
I think 10.5kw is getting towards the top end of electric showers though in terms of power output.....
Having said that - our shower is perfectly decent any time of year. Even when we have to run it at it's 'slowest' in winter, it is still far from being a trickle.I think 10.5kw is getting towards the top end of electric showers though in terms of power output.....
Yep, our cottage shower is only 6 or 7 kW, which isn't enough in winter...
Combi boiler is fine on fhe basis you have only 1 shower and no one is using hot water in the kitchen for example. IMO main benefit is regaining "airing cupboard" space. Pumped power shower imo are better, noise doesn't bother me. Electric showers are very much third best and for use when other options are too difficult or costly.
We got one of these...
http://www.plumbworld.co.uk/aqualisa-quartz-digital-1293-0000?gclid=Cj0KEQjw2ua8BRDeusOkl5qth4QBEiQA8BpQcDjrHZzqM666yED3l45t99xICXLjx3aZ_uwyua55QU4aAqsg8P8HAQ
It's flipping awesome & very quiet. (its so awesome the wife was scared of it at first) 😆
More info needed before anyone can recommend a shower system, or hot water system to be honest.
what type of oil fired cooker is it? Some require a gravity circuit to the hot water cylinder, making unvented much harder to accomodate, thermal store would be suitable though.
Also cylinders connected in series, surely you mean parallel? If not they should be with each pipe the same length for hot supply, cold feed, flow and return.
if you are looking at pumped check the maximum temperature of the hot inlet to the pump either external or integral pump. If it is a gravity system then the maximum temperature may be exceeded.
Also check the duty cycle if you are looking at pumped, some are not continuously rated.
Negative head pump required?
those are just a few I could think of.....
what type of oil fired cooker is it?
Rayburn OF22, I believe...
Some require a gravity circuit to the hot water cylinder, making unvented much harder to accomodate, thermal store would be suitable though.
No intention of changing the hot water circuit for the Rayburn
Also cylinders connected in series, surely you mean parallel? If not they should be with each pipe the same length for hot supply, cold feed, flow and return.
Hhhm, will need to check - but pretty sure in series. Original tank has the hot take off and immersion heater. Rayburn used to boil the tank, so a second was added (late 70s???). Take off for tank 2 feeds base of tank 1. Cold water feed is to base of tank 2.
if you are looking at pumped check the maximum temperature of the hot inlet to the pump either external or integral pump. If it is a gravity system then the maximum temperature may be exceeded.
A good point
Also check the duty cycle if you are looking at pumped, some are not continuously rated.
Pumps I'm looking at are continuously rated
. No.Negative head pump required?
those are just a few I could think of.....
Have done a little more research into what's needed - for shower, pump and hot / cold water system...
As often on STW, the draw of the high spec item is strong - with Grundfos* looking to offer good quality (but at a price!)
Anyone had good service out of a cheaper brand? We've had 10 yrs+ out of a plastic B&Q shower pump, but at 2 bar it's going to be marginal with the larger shower head that we intend to fit in the proposed new shower - looking for 3 bar min
* Grundfos is a brand that is familiar to me through work, so their reputation for reliability is persuasive...
On that basis, presumably no point using a pump on the cold supply as mains pressure sufficient? Just a single impeller positive head pump for the hot water feed?
I was advised to go dual feed when we fitted ours, despite mains pressure being high - restricting the mains as much as pumping the hot. This may or may not be rubbish, but the plumber was fitting it so I went with his preference.
I have fitted a 10.5 Kw electric shower and the cable that is required to do it properly is pretty heavy duty, and a bit of a pain to fit. It's also still nowhere near as good as the power shower (that's what I've always called a pumped system using the hot water).
Stuart Turner are probably near the top of the tree for shower pumps, Grundfoss are ok, as are Salamander. Don't have much experience at the lower end.