Morning all, after a bit of advice from those in the know.
I have a property I rent out, the bath has a shower over which is simply from the taps, ie you pull a knob & water either comes from taps or
shower. We've not had the property long so don't know whether the shower has ever worked properly, but basically if you run a bath water
pressure is reasonable, but probably takes a good 10 - 15 minutes to get a decent bath of hot water.
If you switch it to shower, it works until the shower head gets to about 3 feet off the floor then flow reduces to virtually nothing by the time
you're up at head height, very useful for washing your feet but not much else!.
The top of the hot water tank is around 6 feet off the floor, it is fed from a cold water tank in the loft, the base of which is about 1m above the
top of the hot tank, maybe less
First, am I correct that this is nothing like sufficient head of water to give a decent shower?
Second if that's the case would raising the tank in loft be likely to be sufficient to give an acceptable flow or am I going to need the tank 20
feet up on skyhooks b4 it would do any good. Does increasing the size of the cold tank increase pressure due to additional weight of water or is it
all height dependant?
Third what is the cheapest way of making an acceptable shower, can you get a pump just in the hot line to the tap which will automatically kick in on
hot water demand (I can get an electrical feed reasonably easily) - I obviously don't want to go to the expense of a full "power
shower" unless absolutely necessary, I believe that option also might require a larger hot tank.
I don't want to go to an electric shower as there is no 40A supply available at the fuse box so would involve an additional RCD & possible
part P implications? Also the fuse box is at the other side of the house.
At home I have a system which draws cold from the loft tank, hot directly from it's own feed from top of the hot tank & has it's own
small pump (runs from "normal" electric not needing separate high current feed) is something like that going to be my best option -
tho' still quite a lot of faffing to fit.
Any ideas or info much appreciated
You can get a pump for approx #200 that will raise the pressure of the hot and cold supplies from the tanks.
Did that in my dad's house with the pump just outside and below the hot water cylinder and feeding the hot & cold supplies to the bathroom.
Triton do a shower which uses electricity to power an internal pump but not to heat the water which is taken from your normal hot & cold
supplies.
This means it needs only a 3 amp supply for the pump.
Quite costly though at around £200.
See:
http://www.screwfix.com/p/triton-thermostatic-power-shower-flexible-satin-chrome/66237#
John.
@ Stevebubs Does that have to be fitted to both hot & cold, or can the cold side simply be left disconnected? Cold pressure is fine
@ John P, that sounds like the system I have at home, but does the triton one need to have direct feeds from the cold tank, top of hot tank? Trying to
do this with as little disruption as possible!
[Edited on 5/4/13 by russbost]
Needs to be connected to both but as you have hot and cold to the bath this presumably wouldn't be an issue.
They're quite straightforward to install with inlets which can accept pipes from below, the rear or above (I think!)
John.
PS: I have also installed a pump for the hot water only in a bungalow where the tank gave virtually no pressure.
This was installed adjacent to the hot tank but there's more plumbing required and you need to fit a dip tube in the hot tank. The pump I
fitted was made by Salamander and runs reasonably quietly. I was warned off the Wicks ones which I was told are unreliable although I've no
actual experience of them.
quote:
Originally posted by russbost
@ Stevebubs Does that have to be fitted to both hot & cold, or can the cold side simply be left disconnected? Cold pressure is fine
@ John P, that sounds like the system I have at home, but does the triton one need to have direct feeds from the cold tank, top of hot tank? Trying to do this with as little disruption as possible!
[Edited on 5/4/13 by russbost]
The presure head is from the top of the cold tank, to the height of the outlet.
If it where my house and I where planning to live in it for a while, I would look at converting the house to mains pressure, as it may not be a big
job, at worse, would require a new hot water cylinder which might not be stupid anyway.
However you can equally fit a shower pump, which will locally boost the hot and cold feeds to the shower and give you a suitable shower. You also need
to choose a shower head thats suitable for the provided flowrate, the right head can make a good shower out of really quite low flow. The pump isnt
providing all the energy required in heating the water, so as you say, can often just be run of the ring main.
For referance, 1bar of presure is around 10ft of water head.
Daniel
Single and twin impeller (hot or cold or both) pumps are available. Some good layout info on the Salamander linky.
Single Imp: LINKY
Salamander: LINKY
The Triton T40i seems a common trade solution ....
And nominally rated at 70W
LINKY
[Edited on 5/4/13 by Litemoth]
quote:
Originally posted by John P
Triton do a shower which uses electricity to power an internal pump but not to heat the water which is taken from your normal hot & cold supplies.
This means it needs only a 3 amp supply for the pump.
Quite costly though at around £200.
See:
http://www.screwfix.com/p/triton-thermostatic-power-shower-flexible-satin-chrome/66237#
John.
So far as I can see all of these electric pump assisted showers need a feed from the cold tank rather than the mains, anyone know of a system which
will run from mains pressure, don't really want to have to run fresh feed from the cold tank etc
It all just seems such a pain, I can't believe no one does a system to just boost the pressure a bit on the hot side which is all it needs, this
surely must be a common problem? how much effect does raising the tank in the loft have???
quote:
Originally posted by Litemoth
Single and twin impeller (hot or cold or both) pumps are available. Some good layout info on the Salamander linky.
Single Imp: LINKY
Salamander: LINKY
Am I being a total muppet here, so far as I can see all the links people have posted take both cold & hot & none take direct feed of cold from
the mains feed rather than the tank?
It just seems like using a steam press to crack an eggshell, I obviously need to engage the services of an electrical whiz who understands a bit about
water pressure - this would appear to be an enormous hole in the market! This time next year we'll be millionaires! 
When I looked into putting a shower pump on our mains shower it wasn't allowed. Can't remember the exact reason but it was why they aren't available!!
quote:
Originally posted by russbost
The top of the hot water tank is around 6 feet off the floor, it is fed from a cold water tank in the loft, the base of which is about 1m above the top of the hot tank, maybe less
First, am I correct that this is nothing like sufficient head of water to give a decent shower?
quote:
Originally posted by Ben_Copeland
When I looked into putting a shower pump on our mains shower it wasn't allowed. Can't remember the exact reason but it was why they aren't available!!
If I've got this correct your cold water in the bathroom is at mains pressure but the hot comes from a conventional hot tank fed from the cold
tank which is why you have enough cold pressure but not hot.
The Salamanda pump I fitted close to the hot tank was for exactly this reason.
It was a single impellor pump which takes it's hot feed from a dip tube in the top of the hot tank then pumps at pressure to all the hot outlets
so the bath and basin will also get higher pressure hot water.
The cold is left as it is at mains pressure.
This worked fine just needs a bit more plumbing as you have to remove the existing hot outlet at the tank and fit the dip tube assembly. (Think
it's actually called a Surrey Flange).
John.
quote:
Originally posted by dhutch
The presure head is from the top of the cold tank, to the height of the outlet.
For referance, 1bar of presure is around 10ft of water head.
Daniel
OK, last go.
Drop the mains pressure with a PRV and use a Trition T40i
PRV LINKY
...just a thought, there may be a ball valve fitted inline between tank and the shower restricting flow?
there used to be a shower unit that used mains cold pressure to create a venturi effect to boost the hot water pressure no electrics required.i cant remember the name of the manufacturer though
I hadn't heard of these before but apparently Trevi do a range of venturi showers.
The web site states:
"Venturi Mixer Showers
High pressure mains cold water is used to
‘pull through’ tank pressure water through the
special venturi valve inside the shower control,
so the resulting mixed water comes out at a
much greater rate than could be achieved using
an electric shower or ordinary shower mixer
valve. Gives excellent showering performance
in conditions that are often deemed unsuitable
for conventional thermostatic showers
eg. guest rooms, en-suites, attic bathrooms.
Ideal alternative to an electric shower."
See
http://www.ishop.co.uk/ishop/images/1068/Trevi_trevi_2009.pdf
I'd be interested in how effective this is if you decide to try it.
John.
thats the one.brother in law has one.and yes they do work
Many thanx for all the info guys, at least now I have a few ideas of what can & can't be acheived. I actually had one of those venturi
showers in a house I lived in about 16 years ago - worked quite well, I didn't think they were available anymore & didn't know what they
were called to google them.
@John P the Salamander single impellor pump you used pumps purely the hot water, no connection to the cold system - have I go that right? & would
be put in on a surrey flange from the top of the tank to feed just the bathroom - have I got that right?
I obviously need to do a bit more investigative work re the taps & existing pipework, but I'm sure it's going to need some sort of
assistance.
Thanx again!
That's basically what I did although it feeds all the hot water outlets so also increases hot water flow in the kitchen etc.
You disconnect the outlet pipe from the top of the hot water cylinder and replace it with the Surry Flange. (Be aware that the thread in the top of
the cylinder can vary, I had a bit of a problem sourcing the correct sized flange).
The flange has a dip tube which goes down into the cylinder so that the pump draws water from around 200 mm down. There are two outlet connections
on the flange, one of which is vertical and goes to the vent pipe whilst the other horizontal outlet goes to the hot water feed.
The pump goes on the floor adjacent to the cylinder and has flexible connectors to help isolate mechanical vibration from the pipework.
The electrical load is quite small so we just plugged it into the existing (unused) immersion heater socket.
John.
I have a shower with 2 central heating pumps installed, I did not want a noisy pump or to much pressure so simply fitted 2 domestic heating pumps one
in the cold supply fed from the bottom of the cold tank and one into the hot outlet from the hot water tank .I did not need to use a flange outlet and
dip tube as I would if fitting a higher power pump but the output is sufficient for a good shower and the pumps can hardy be heard running.
I also actually have a Stuart turner 3 bar single pump with built in flow switch
in near new condition that I was going to fit but then never used so that could be an option if your interested in buying it .
Paul
quote:
Originally posted by paulf
I have a shower with 2 central heating pumps installed, I did not want a noisy pump or to much pressure so simply fitted 2 domestic heating pumps one in the cold supply fed from the bottom of the cold tank and one into the hot outlet from the hot water tank .I did not need to use a flange outlet and dip tube as I would if fitting a higher power pump but the output is sufficient for a good shower and the pumps can hardy be heard running.
I also actually have a Stuart turner 3 bar single pump with built in flow switch
in near new condition that I was going to fit but then never used so that could be an option if your interested in buying it .
Paul
I have used 2 normal central heating pumps with a pull switch on the ceiling to turn them on and off.I was going to fit a flow switch as well but
never got around to it , even if someone forgets to turn them off after use it doesn't appear to cause a problem as have been installed for about
18 months and work fine.I did see the grundfoss ones in your link but ended up using 2 cheap tool station CH pumps ,I dont know if using one on its
own would work very well as if you have mains pressure cold water and pumped hot then the pressure differential may be to great for the mixer valve to
work correctly therefore I took a cold feed from the bottom of the header tank and the hot from the hot water tank outlet with the pump mounted near
the bottom of the tank.
Paul
quote:
Originally posted by russbost
quote:
Originally posted by paulf
I have a shower with 2 central heating pumps installed, I did not want a noisy pump or to much pressure so simply fitted 2 domestic heating pumps one in the cold supply fed from the bottom of the cold tank and one into the hot outlet from the hot water tank .I did not need to use a flange outlet and dip tube as I would if fitting a higher power pump but the output is sufficient for a good shower and the pumps can hardy be heard running.
I also actually have a Stuart turner 3 bar single pump with built in flow switch
in near new condition that I was going to fit but then never used so that could be an option if your interested in buying it .
Paul
Hi Paul
The pumps you've used , do they have built in flow valves? If not, how is the syatem triggered to pump. I'm wondering if they are something like this
link
which appears to be basically a central heating pump with a flow switch fitted - this seems like it might do what I want & save messing around with surrey flange etc. so far as I can see it's intended to simply fit in line in existing pipework. Anyone ever used one of these?
I have used 2 normal central heating pumps with a pull switch on the ceiling to turn them on and off.I was going to fit a flow switch as well but
never got around to it , even if someone forgets to turn them off after use it doesn't appear to cause a problem as have been installed for about
18 months and work fine.I did see the grundfoss ones in your link but ended up using 2 cheap tool station CH pumps ,I dont know if using one on its
own would work very well as if you have mains pressure cold water and pumped hot then the pressure differential may be to great for the mixer valve to
work correctly therefore I took a cold feed from the bottom of the header tank and the hot from the hot water tank outlet with the pump mounted near
the bottom of the tank.
Paul
quote:
Originally posted by russbost
quote:
Originally posted by paulf
I have a shower with 2 central heating pumps installed, I did not want a noisy pump or to much pressure so simply fitted 2 domestic heating pumps one in the cold supply fed from the bottom of the cold tank and one into the hot outlet from the hot water tank .I did not need to use a flange outlet and dip tube as I would if fitting a higher power pump but the output is sufficient for a good shower and the pumps can hardy be heard running.
I also actually have a Stuart turner 3 bar single pump with built in flow switch
in near new condition that I was going to fit but then never used so that could be an option if your interested in buying it .
Paul
Hi Paul
The pumps you've used , do they have built in flow valves? If not, how is the syatem triggered to pump. I'm wondering if they are something like this
link
which appears to be basically a central heating pump with a flow switch fitted - this seems like it might do what I want & save messing around with surrey flange etc. so far as I can see it's intended to simply fit in line in existing pipework. Anyone ever used one of these?
As far as I can see that would increase the cold water pressure but your hot supply would still depend on the head created by the cold tank.
If you were considering fitting this is the flow from the hot tank then you would really still need the surrey flange to ensure the suction side of
the pump doesn't draw in air from the vent pipe.
To be honest fitting the flange isn't really difficult and as a single impellor pump can simply sit on the floor next to the hot tank
there's not that much plumbing to do.
The only thing to be careful about is when removing the existing fitting from the top of the tank. I soaked mine in WD40 and it came out fairly
easily, just be careful not to damage the boss which is fitted to the tank as although the treaded portion is quite strong it's only mounted on
the thin copper of the tank.
John.
"The only thing to be careful about is when removing the existing fitting from the top of the tank. I soaked mine in WD40 and it came out fairly
easily, just be careful not to damage the boss which is fitted to the tank as although the treaded portion is quite strong it's only mounted on
the thin copper of the tank. "
That's the bit that was bothering me - I've played this game b4!
Whilst I'd still do it with the correct fitting I have just come across this advice on ukplumbersforums.co.uk (No idea how sound this advice is
though!)
______________________________________________________________________________________________
"Only ever fitted an Essex flange once (during training course) and had the same Surrey flange sitting on the van for nearly 4 years (still in
box) .
Fitted loads of Salamander shower pumps and always tee-ed off the horizontal run off the top of the cylinder.
Cut in to horizontal run and slide on a 22mm equal tee and angle the tee down at 45 degrees to "discourage" pump aeration but giving pump
hot feed primacy on system.
Continue feed in nice flowing bends where possible (or 45 degree elbows) and keep it in 22mm until just before pump then step down to 15mm at last
minute as it where.
Salamander pumps are more compact than the rest and are my favourite by a country mile (you can tell by the sheer weight of them that they are solid
machines). They can be squeezed into airing cupboards where others can't.
Yes,,,I know what I've said above contradicts the Salamander instructions,, but in my opinion those instructions have a degree of overkill and
are written for those who may have less understanding of fluidic flows and associated systems.
_______________________________________________________________________________________________
Yeah, I've seen some diagrams (might be on the salamander site, I've looked at so many now it's all a bit of a blur!) where they tee into the top pipe from the tank at 45 degrees, I have to say I can't see why teeing in at 45 rather than in the vertical pipe makes it less likely to pull air in from the vent. I'm going to take a look at the whole setup tomorrow, so will have a better idea then what I can do with it!