Shower pump vs power shower unit?
Discussion
Heya
We need to update our bathroom; originally we were goin to have the whole thing replaced, but just don't have the cash now.
The main problem is the lack of shower - we have a bath with a mixer tap, but not enough water pressure to make it a stand-up shower.
Having a look online it seems I can either get a "power shower unit", or I can get a pump. Does anybody know what the pro's and con's are for each, and which tends to be the better option?
With a pump I suppose I couldn't have a mixer, as it would end up pressurising the bath water?
Complete DIY beginner so any advice welcome! Thanks
We need to update our bathroom; originally we were goin to have the whole thing replaced, but just don't have the cash now.
The main problem is the lack of shower - we have a bath with a mixer tap, but not enough water pressure to make it a stand-up shower.
Having a look online it seems I can either get a "power shower unit", or I can get a pump. Does anybody know what the pro's and con's are for each, and which tends to be the better option?
With a pump I suppose I couldn't have a mixer, as it would end up pressurising the bath water?
Complete DIY beginner so any advice welcome! Thanks

A power shower is an all in one unit so i guess its easier to fit and cheaper.
A shower pump is hidden away behind a wall, under a bath etc, requires it own elec and water supply. You would also then need to purchase a shower unit which controls hot/cold, flow etc. Expensive but more plush way of doing it i suppose.
I have used both and in your situation the all in one makes more sense.
A shower pump is hidden away behind a wall, under a bath etc, requires it own elec and water supply. You would also then need to purchase a shower unit which controls hot/cold, flow etc. Expensive but more plush way of doing it i suppose.
I have used both and in your situation the all in one makes more sense.
A pump will use your existing hot water whereas a power shower unit will (I think) heat the cold water on its way through. The significance of this is that the power shower may require a new electrical circuit if the power requirement means that you need thicker cable to it. Note this is just my thoughts on the matter - not having a power-shower unit I don't know if this is the case, but its worth thinking about.
We have a pump which is fine. Buy a standard shower fitting and plumb it in so that the pump only serves the shower.
We have a pump which is fine. Buy a standard shower fitting and plumb it in so that the pump only serves the shower.
Don't know what setup you have so it might not work, but could you not pump both the hot and cold water via a twin impeller pump. Normally the pump is in the airing cupboard or loft which hides the noise.
Having the pump in the shower with you is a bloody noise and outdated way of doing things.
Having the pump in the shower with you is a bloody noise and outdated way of doing things.
TooLateForAName said:
A pump will use your existing hot water whereas a power shower unit will (I think) heat the cold water on its way through. The significance of this is that the power shower may require a new electrical circuit if the power requirement means that you need thicker cable to it. Note this is just my thoughts on the matter - not having a power-shower unit I don't know if this is the case, but its worth thinking about.
We have a pump which is fine. Buy a standard shower fitting and plumb it in so that the pump only serves the shower.
Mine uses existing cold and hot inlet, (Dont ask me why the Dolphin "Engineer" plumbed it arse about face), power shower just increases outlet pressure.We have a pump which is fine. Buy a standard shower fitting and plumb it in so that the pump only serves the shower.
Either way, both will deliver more hot water than just existing water pressure, so maybe just down to personal preference, and cost of course.

Gingerbread Man said:
Don't know what setup you have so it might not work, but could you not pump both the hot and cold water via a twin impeller pump. Normally the pump is in the airing cupboard or loft which hides the noise.
Having the pump in the shower with you is a bloody noise and outdated way of doing things.
Thank you, but I have no idea what that means :sHaving the pump in the shower with you is a bloody noise and outdated way of doing things.
I thought a pump might sit in the airing cupboard (which is next to the bathroom on the same wall as the bath taps)?
Also I think the power shower units can be bought without a heater element; i.e. just use the existing hot water....
We updated our bathrooms from and including similar situations to what you're talking about.
Originally there was a 'power shower' that used a cold feed pipe only and required a power connection that was in our airing cupboard next to the bathroom. The down side of power showers is that they don't give you the clean lines that a pumped shower does (at least not without spending a fortune).
Based on the fact we had a hot water cylinder at the same level as the shower, when we replaced the shower (Damixa G-type) we went with a separate pump that fed the shower only. Cold water pressure (mains) was fine and we just got a B&Q pump for the hot water from the cylinder.
We then replaced the boiler/cylinder with a combi set-up and used the same shower and took the pump out of the system. The boiler provided hot water at a suitable pressure and we continued to use the basic mains pressure cold water.
The pump was audible when running but gave a decent shower pressure, the combi is possibly a bit far away to give an equivalent pressure, but is adequate. The pump will of course draw down the hot water cylinder quicker than before and will mean the next person in the bathroom may not get enough hot water (depends on size of tank obviously), whereas the power shower will go on as long as you want.
Dr Rick
Originally there was a 'power shower' that used a cold feed pipe only and required a power connection that was in our airing cupboard next to the bathroom. The down side of power showers is that they don't give you the clean lines that a pumped shower does (at least not without spending a fortune).
Based on the fact we had a hot water cylinder at the same level as the shower, when we replaced the shower (Damixa G-type) we went with a separate pump that fed the shower only. Cold water pressure (mains) was fine and we just got a B&Q pump for the hot water from the cylinder.
We then replaced the boiler/cylinder with a combi set-up and used the same shower and took the pump out of the system. The boiler provided hot water at a suitable pressure and we continued to use the basic mains pressure cold water.
The pump was audible when running but gave a decent shower pressure, the combi is possibly a bit far away to give an equivalent pressure, but is adequate. The pump will of course draw down the hot water cylinder quicker than before and will mean the next person in the bathroom may not get enough hot water (depends on size of tank obviously), whereas the power shower will go on as long as you want.
Dr Rick
We had a twin impeller pump in the shower room behind the unit plinth. These must be fed from gravity hot & cold system not mains pressure iirc. Was not very noisy-gave a great shower. The temerature/presures of the shower was not affected if anyone flushed the loo or opened a tap etc.
Never had any trouble running the hot/cold tanks empty even after two or three showers.
Used a thermostaic shower head.
Just removed the pump due to changing the heating system to a combi boiler. Shower now is adequate but no where near as good as with the pump.
Never had any trouble running the hot/cold tanks empty even after two or three showers.
Used a thermostaic shower head.
Just removed the pump due to changing the heating system to a combi boiler. Shower now is adequate but no where near as good as with the pump.
dreamer75 said:
Gingerbread Man said:
Don't know what setup you have so it might not work, but could you not pump both the hot and cold water via a twin impeller pump. Normally the pump is in the airing cupboard or loft which hides the noise.
Having the pump in the shower with you is a bloody noise and outdated way of doing things.
Thank you, but I have no idea what that means :sHaving the pump in the shower with you is a bloody noise and outdated way of doing things.
I thought a pump might sit in the airing cupboard (which is next to the bathroom on the same wall as the bath taps)?
Also I think the power shower units can be bought without a heater element; i.e. just use the existing hot water....
This is the same idea a Simpo has mentioned, the pump he shows normally comes with a shower in a kit, such as an aqualisa setup.
Having a shower on the wall of the shower with the pump in it's housing is a bloody noisey option. You don't need it to have a heating element either as you've got the cylinder next door, just need some extra pressure.
What kind of boiler/hot water system do you have? If it is a combi then you cannot have a shower pump as these need to be fed off a hot water cylinder.
A power shower heats the water as it passes through it so it needs tons of electricity (~10Kw) and 10mm wiring direct from your consumer unit. Even with that power they can still be a lukewarm when the incoming water is cold like in this weather.
There are also power showers that take a hot and cold feed and just use electric to pump it but in my experience they are pretty crap.
A power shower heats the water as it passes through it so it needs tons of electricity (~10Kw) and 10mm wiring direct from your consumer unit. Even with that power they can still be a lukewarm when the incoming water is cold like in this weather.
There are also power showers that take a hot and cold feed and just use electric to pump it but in my experience they are pretty crap.
Gingerbread Man said:
This is the same idea a Simpo has mentioned, the pump he shows normally comes with a shower in a kit, such as an aqualisa setup.
It was indeed. Not only very good quality (real metal and chrome rather than silver-coloured plastic) but also fittable by a competent DIYer.Thanks everyone 
Its not a combi boiler, just a normal one which heats the hot water tank / heating.
So the twin impeller jobby doesn't "pump" as such, it just sort of enhances gravity? So it's quieter? But is it ok if the hot water tank is on the same level as the shower or lower?
The cold water tank is in the loft but pressure is still woeful, and the hot water tank is in the airing cupboard next to the bathroom (the wall the shower is on is the same one the airing cupboard is on).
Can anybody give me a rough idea what a twin impeller pump should cost? Going to phone up plumbers for quotes and would like an idea first?

Its not a combi boiler, just a normal one which heats the hot water tank / heating.
So the twin impeller jobby doesn't "pump" as such, it just sort of enhances gravity? So it's quieter? But is it ok if the hot water tank is on the same level as the shower or lower?
The cold water tank is in the loft but pressure is still woeful, and the hot water tank is in the airing cupboard next to the bathroom (the wall the shower is on is the same one the airing cupboard is on).
Can anybody give me a rough idea what a twin impeller pump should cost? Going to phone up plumbers for quotes and would like an idea first?
dreamer75 said:
...is it ok if the hot water tank is on the same level as the shower or lower?
The cold water tank is in the loft but pressure is still woeful, and the hot water tank is in the airing cupboard next to the bathroom (the wall the shower is on is the same one the airing cupboard is on).
Height between tank and showerhead is the important distance, the position of the hot water cylinder is largely unimportant. Most twin impellers will fire quite well on as little as 500mm, but some may struggle particularly if the mixer valve doesn't flow very well. In these cases you'd be better off with a negative head pump, which is more expensive.The cold water tank is in the loft but pressure is still woeful, and the hot water tank is in the airing cupboard next to the bathroom (the wall the shower is on is the same one the airing cupboard is on).
Power shower = wall unit with built in pump no heating element. Requires stored hot water tank and low amp electric feed.
Electric shower = wall unit with built in heater. Requires mains cold water and high amp electric feed.
Separate pumps come in two varieties, shower pumps and whole house pumps.
Shower pumps can only be used to increase the pressure to a mixer shower as both sides (hot and cold) must be operated at the same time.
Whole house pumps can be feed all the taps in the house as well as the shower. They are capable of running the hot and cold sides independently of each other. A lot of modern taps are designed to use high pressure hot and cold water, a whole house pump allows you to use these taps from a stored hot water cylinder with a decent flow rate.
Electric shower = wall unit with built in heater. Requires mains cold water and high amp electric feed.
Separate pumps come in two varieties, shower pumps and whole house pumps.
Shower pumps can only be used to increase the pressure to a mixer shower as both sides (hot and cold) must be operated at the same time.
Whole house pumps can be feed all the taps in the house as well as the shower. They are capable of running the hot and cold sides independently of each other. A lot of modern taps are designed to use high pressure hot and cold water, a whole house pump allows you to use these taps from a stored hot water cylinder with a decent flow rate.
The position of the hot tank is unimportant - it's the cold tank that provides the head to both hot and cold. If it's water surface is a couple of metres above the shower head it'll work *adequately* but not torrentially. Aqualisa claim to handle unpumped low head situations best and are (if I recall) plumbed in 22mm rather than 15mm
We have a Triton power shower. It's has a built in pump but does not heat the water. It is quite noisy, if I was doing the bathroom again with a bigger budget, I would replace it with a pump in the airing cupboard and a stylish mixer unit in the bathroom.
As said before this type of setup runs off a gravity fed hot and cold system with a big header tank in the loft. From the header tank are two feeds, one to the cold side of the shower and one to the hot water cylinder, which in turn feeds the hot side of the shower (along with all the other hot taps).
The only thing which I think hasn't been mentioned is consider the size of your hot water cylinder. If you like a really hot shower and/or jet wash levels cleaning power it can empty our hot cylinder very quickly indeed. I don't actually know what capacity our cylinder is so I can't help on that front.
Oh, and what ever type of shower you get, choose one with a thermostatic mixer, it means you get a much more comfortable experience as temp of the hot water system varies.
As said before this type of setup runs off a gravity fed hot and cold system with a big header tank in the loft. From the header tank are two feeds, one to the cold side of the shower and one to the hot water cylinder, which in turn feeds the hot side of the shower (along with all the other hot taps).
The only thing which I think hasn't been mentioned is consider the size of your hot water cylinder. If you like a really hot shower and/or jet wash levels cleaning power it can empty our hot cylinder very quickly indeed. I don't actually know what capacity our cylinder is so I can't help on that front.
Oh, and what ever type of shower you get, choose one with a thermostatic mixer, it means you get a much more comfortable experience as temp of the hot water system varies.
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