Use mains water throughout the house

8Choc

Hi, I was thinking of putting a tee connector on the mains feed to my attic tank and connecting to another tee on the output from the tank , and also putting a one way valve between the new tee on the output and the tank itself ( to stop the tank filling from the output) , has anybody ever done this ?, or know why it wouldn't work ? .I am trying to increase pressure in the house specifically the upstairs shower . As a test I fed the garden hose ( main fed ) through the upstairs bathroom window and experimented by filling a litre plastic bottle with the shower ( head off ) and then the garden hose and the hose filled it twice as fast !. Would anyone with experience know why I couldn't do this ?. Thanks in advance

K.Flyer

8Choc wrote: »

Hi, I was thinking of putting a tee connector on the mains feed to my attic tank and connecting to another tee on the output from the tank , and also putting a one way valve between the new tee on the output and the tank itself ( to stop the tank filling from the output) , has anybody ever done this ?, or know why it wouldn't work ? .I am trying to increase pressure in the house specifically the upstairs shower . As a test I fed the garden hose ( main fed ) through the upstairs bathroom window and experimented by filling a litre plastic bottle with the shower ( head off ) and then the garden hose and the hose filled it twice as fast !. Would anyone with experience know why I couldn't do this ?. Thanks in advance

You cannot do what you are thinking of without it ending in tears and a very wet house.

What type of shower is it?
Usually the cheapest way to boost your water pressure, especially for a shower, is by installing a water pump or a pumped unit like a Triton AS-2000.

8Choc

Thanks for reply - Why Tears ? Its a new gravity fed shower , works quite well but could do with a boost. Pumps etc. cost money , the pressure in the incoming mains is free etc.etc....

K.Flyer

8Choc wrote: »

Thanks for reply - Why Tears ? Its a new gravity fed shower , works quite well but could do with a boost. Pumps etc. cost money , the pressure in the incoming mains is free etc.etc....

Your going to boost the cold water, what about the hot water??

8Choc

Your right K.Flyer , there are separate feeds for hot and cold from the tank, so I just tee into both ?

my3cents

The downside to your plan OP is that you will increase the noise from water flowing in the pipes when you use any of the cold taps and flush the toilet. I know because my parents house is plumbed that way, flush a toilet and you wake the dead.

Another problem is at times of low demand on the water main late at night the pressure can go well above what it is during the day. Your header tank evens that all out.

A gravity fed shower is low pressure so how will it perform with varying mains pressure?

K.Flyer

8Choc wrote: »

Your right K.Flyer , there are separate feeds for hot and cold from the tank, so I just tee into both ?

Nope, this is where the trouble can start.
If you have a standard domestic hot water cylinder you will most likely cause it to leak as they are not designed to take high pressure mains water.
The mains water will just push back up through the open vent pipe overhanging the tank, if you blank it off, which is what I have seen done, then the pressure builds up in the cylinder, add some heat for hot water and kersplash.
I understand your thinking, but honestly its a bad idea.
You could change the cylinder for an unvented type, but it would be cheaper to fit a pump.

Mech1

Also if for any reason the mains water goes off your stagnant and possibly dirty infected water system might siphon back into our treated clean water supply.

8Choc

Thanks - don't get the noise thing , don't understand how it would be different ? Toilet cistern would just fill quicker ? . With regards to the pressure, I checked it there earlier 6pm on a friday ( busy time , people heading out etc.etc. ) and pressure was really good . I was wrong do to say I'd use a oneway valve to stop the tank from filling from the output cause that would never open even if mains water was switched off, probably should use a pressure valve of some type (takes feed from highest pressure , i.e. if mains went off it would switch back to tank ) or even a manual valve ( if mains went off you could turn it open and have have the 100 litres in the tank available etc..) or even get rid of the tank altogether ( how often does the water go off these days ??? )

K.Flyer

Did you not read my post in relation to the Hot Water Cylinder, standard household cylinders are not designed to be sealed or be subjected to mains water pressure.

my3cents

K.Flyer wrote: »

Did you not read my post in relation to the Hot Water Cylinder, standard household cylinders are not designed to be sealed or be subjected to mains water pressure.

I can remember a neighbor connecting a std HWC directly to the mains and the interesting thing was is lasted a few days before it opened up down the side seam.

Lu Tze

Interesting idea, possibly the inclusion of a pressure reducing valve limiting the the pressure might relieve the the hot water tank issues. Could be 60-80m of head in the water main, reducing to 10-12m would still double the pressure in the house water system. Pretty disastrous if it goes wrong though

K.Flyer

Lu Tze wrote: »

Interesting idea, possibly the inclusion of a pressure reducing valve limiting the the pressure might relieve the the hot water tank issues. Could be 60-80m of head in the water main, reducing to 10-12m would still double the pressure in the house water system. Pretty disastrous if it goes wrong though

What about the water flowing back up through the open vent pipe from the cylinder and pitching back into the attic tank causing it to overfill?

Lu Tze

K.Flyer wrote: »

What about the water flowing back up through the open vent pipe from the cylinder and pitching back into the attic tank causing it to overfill?

Fair enough, while water system design is something I do, I'm not ofay with household plumbing systems. Was just suggesting a solution for reducing the excessive mains pressure to something more reasonable, but still in excess of the head available from the attic tank.

8Choc

Thanks K.Flyer , I knew i was missing something,  the hot water tank vent pipe , thought I was a genius there for a minute........... Maybe a pressure relief valve on the vent pipe ? , Mains pressure at that height cant be enough to breach a cylinder. etc ...???.

K.Flyer

The correct equipment is available and it's becoming increasingly common to find on new and retro installations complete with the appropriate safety devices to minimise or prevent property damage and personal harm.
But attempting what the O.P. is suuggesting is a recipe for disaster.

Dtp1979

Lu Tze wrote: »

Interesting idea, possibly the inclusion of a pressure reducing valve limiting the the pressure might relieve the the hot water tank issues. Could be 60-80m of head in the water main, reducing to 10-12m would still double the pressure in the house water system. Pretty disastrous if it goes wrong though

No no no. God read k flyers post. If you blank off the vent and pressurise the plumbing then it needs to expand to say the least. There's no way around any of this without flooding a house. Install a booster pump op if you want better pressure

K.Flyer

8Choc wrote: »

Thanks K.Flyer , I knew i was missing something,  the hot water tank vent pipe , thought I was a genius there for a minute........... Maybe a pressure relief valve on the vent pipe ? , Mains pressure at that height cant be enough to breach a cylinder. etc ...???.

You are asking for trouble, advise given, take it or leave it, but in a nutshell, if you do attempt it and it all goes wrong, you will have some explaining to do with your household insurance company :pac:

Dtp1979

K.Flyer wrote: »

You are asking for trouble, advise given, take it or leave it, but in a nutshell, if you do attempt it and it all goes wrong, you will have some explaining to do with your household insurance company :pac:

And to the plumber who comes to fix it, and to the guy who's re slabbing your ceiling, and to the plasterer, and to the guy re laying new carpets. And to your missus. God help you

gctest50

8Choc wrote: »

Thanks K.Flyer , I knew i was missing something,  the hot water tank vent pipe , thought I was a genius there for a minute........... Maybe a pressure relief valve on the vent pipe ? , Mains pressure at that height cant be enough to breach a cylinder. etc ...???.

Block the vent pipe and you get this sorta craic happening:

with a few rough measurements

Needles73

8Choc wrote: »

Hi, I was thinking of putting a tee connector on the mains feed to my attic tank and connecting to another tee on the output from the tank , and also putting a one way valve between the new tee on the output and the tank itself ( to stop the tank filling from the output) , has anybody ever done this ?, or know why it wouldn't work ? .I am trying to increase pressure in the house specifically the upstairs shower . As a test I fed the garden hose ( main fed ) through the upstairs bathroom window and experimented by filling a litre plastic bottle with the shower ( head off ) and then the garden hose and the hose filled it twice as fast !. Would anyone with experience know why I couldn't do this ?. Thanks in advance

Ignoring all the safety aspects running mains around the house will result in potential condensation problems. Cold fresh water into a warm house and cisterns can be an issue

8Choc

Do he think just supplying the shower with mains cold only would improve the pressure ? or would you just end up turning the cold down to balance with the tank fed hot etc...

listermint

Genuine question.

Why don't you just buy a pump like you are supposed to .

Paul Kiernan

I have a new build and was planning pumped DHW with a buffer tank and Grundfos pressure pump. I have a combi boiler with no immersion. As the location for the tank and pump isn't ready yet I thought (as a temporary solution) I'd connect the whole system directly to the mains which I did yesterday!

I kept the cold inlet valve to the boiler closed so only the cold is active.

As long as a tap is running everything is fine but when I turn off all the taps the pressure builds up to about 2 bar after a couple of minutes. Then when I turn on a tap, kerboom! Water shoots out under high pressure for about a minute, splashing everywhere, and then settles down!

Is there anything I can do to get my water running safely until my tank/pump can be installed?

K.Flyer

8Choc wrote: »

Do he think just supplying the shower with mains cold only would improve the pressure ? or would you just end up turning the cold down to balance with the tank fed hot etc...

No, it won't work due to pressure differences.
Anyway, if you turned the pressure right down to match the tank fed hot pressure, you are back to square one.

K.Flyer

Paul Kiernan wrote: »

I have a new build and was planning pumped DHW with a buffer tank and Grundfos pressure pump. I have a combi boiler with no immersion. As the location for the tank and pump isn't ready yet I thought (as a temporary solution) I'd connect the whole system directly to the mains which I did yesterday!

I kept the cold inlet valve to the boiler closed so only the cold is active.

As long as a tap is running everything is fine but when I turn off all the taps the pressure builds up to about 2 bar after a couple of minutes. Then when I turn on a tap, kerboom! Water shoots out under high pressure for about a minute, splashing everywhere, and then settles down!

Is there anything I can do to get my water running safely until my tank/pump can be installed?

Open the tap slower

You could fit a pressure reducing valve with a pressure gauge, but I think you are wasting your money and effort as 2 - 3 bar is normal on a pressurised system, which is what you will have when its all set up and finished.

8Choc

K.Flyer wrote: »

No, it won't work due to pressure differences.
Anyway, if you turned the pressure right down to match the tank fed hot pressure, you are back to square one.

Thanks, yep just thinking as well that someone could get scalded if for some reason the mains switched off !!

8Choc

Paul Kiernan wrote: »

I have a new build and was planning pumped DHW with a buffer tank and Grundfos pressure pump. I have a combi boiler with no immersion. As the location for the tank and pump isn't ready yet I thought (as a temporary solution) I'd connect the whole system directly to the mains which I did yesterday!

I kept the cold inlet valve to the boiler closed so only the cold is active.

As long as a tap is running everything is fine but when I turn off all the taps the pressure builds up to about 2 bar after a couple of minutes. Then when I turn on a tap, kerboom! Water shoots out under high pressure for about a minute, splashing everywhere, and then settles down!

Is there anything I can do to get my water running safely until my tank/pump can be installed?

Close the mains valve a bit , the one out on the road ? Would that work ?

Dtp1979

8Choc wrote: »

Thanks, yep just thinking as well that someone could get scalded if for some reason the mains switched off !!

. I'd say your taps are to blame or the design of the basin.

Dtp1979

Dtp1979 wrote: »

. I'd say your taps are to blame or the design of the basin.

Sorry wrong quote

8Choc

Dtp1979 wrote: »

If the mains is off then you won't have hot water. Therefore I scalding. I'd say your taps are to blame or the design of the basin.

You would have hot water cause the tank in the attic would be full ?

Taps are fine was just trying to think of a way to boost the shower a bit without buying a pump

8Choc

Crazy idea No.3 ☺

What if ...........

1. Remove attic header tank altogether.

2. Connect cold water directly to mains.

3. Put a small header tank (with ballcock/valve ) in the attic and have the hot water tank vent pipe fill this , the ball clock valve in this tank then controls a mains feed to the hot water tank.

When you turn on hot water you would initially have gravity pressure but as the ballcock valve opens it would switch to mains pressure ?

The hot water tank is also constantly vented through the new tank so it won't launch into orbit like the ones in the video earlier

This new tank would have to be insulated, maybe even could go at top of hot press if small enough....

This is all theoretical , in case yer worried about me ☺

K.Flyer

8Choc wrote: »

...just trying to think of a way to boost the shower a bit without buying a pump

None of your previous ideas are viable, or for that matter, safe.
There are correct methods to achieve higher water pressure, but not the way you are looking at it.
A simple thing to look at is the shower hose and shower head.
Generally the hoses come in three different internal bore sizes, go buy the largest one. Then look at the shower heads and buy the one with the highest water flow rate, do not buy the "water saver" type.
This should make a difference as to how much water you get having a shower.

K.Flyer

8Choc wrote: »

Crazy idea No.3 ☺

What if ...........

1. Remove attic header tank altogether.

2. Connect cold water directly to mains.

3. Put a small header tank (with ballcock/valve ) in the attic and have the hot water tank vent pipe fill this , the ball clock valve in this tank then controls a mains feed to the hot water tank.

When you turn on hot water you would initially have gravity pressure but as the ballcock valve opens it would switch to mains pressure ?

The hot water tank is also constantly vented through the new tank so it won't launch into orbit like the ones in the video earlier

This new tank would have to be insulated, maybe even could go at top of hot press if small enough....

This is all theoretical , in case yer worried about me ☺

Just no!

Del2005

Could you just raise the cold water tank in the attic? My sister had terrible water pressure in her shower with the cold water tank on the floor of the attic. They partially floored the attic and moved the cold water tank to near the apex of the roof and have great pressure now.

Dtp1979

Del2005 wrote: »

Could you just raise the cold water tank in the attic? My sister had terrible water pressure in her shower with the cold water tank on the floor of the attic. They partially floored the attic and moved the cold water tank to near the apex of the roof and have great pressure now.

Apart from buying a pump that's probably the only other solution. But the difference wouldn't be that big I'd say

8Choc

K.Flyer wrote: »

8Choc wrote: »

Crazy idea No.3 ☺

What if ...........

1. Remove attic header tank altogether.

2. Connect cold water directly to mains.

3. Put a small header tank (with ballcock/valve ) in the attic and have the hot water tank vent pipe fill this , the ball clock valve in this tank then controls a mains feed to the hot water tank.

When you turn on hot water you would initially have gravity pressure but as the ballcock valve opens it would switch to mains pressure ?

The hot water tank is also constantly vented through the new tank so it won't launch into orbit like the ones in the video earlier

This new tank would have to be insulated, maybe even could go at top of hot press if small enough....

This is all theoretical , in case yer worried about me ☺

Just no!

:-) , Wait till ye here my idea's to improve the electricity supply around the house :-)  :-)

The above wouldn't work anyway as you would have to be emptying that hot water header tank quicker than the mains was filling it etc....

Dtp1979

8Choc wrote: »

:-) , Wait till ye here my idea's to improve the electricity supply around the house :-)  :-)

The above wouldn't work anyway as you would have to be emptying that hot water header tank quicker than the mains was filling it etc....

No it wouldn't work because it's crazy

8Choc

Del2005 wrote: »

Could you just raise the cold water tank in the attic? My sister had terrible water pressure in her shower with the cold water tank on the floor of the attic. They partially floored the attic and moved the cold water tank to near the apex of the roof and have great pressure now.

Thanks - I looked at this before , its a Dormer bungalow so the attic space is quite low , I could probably raise the tank by 50cm or so but don't think that would do much .
 Often thought that they should shape these tanks so they could be fitted right up into the appex of the attic roof , where you would get max pressure ..........

listermint

Put the tank on stilts outside , about twenty foot in the air should do it .

my3cents

listermint wrote: »

Put the tank on stilts outside , about twenty foot in the air should do it .

Or dig a very deep cellar and move the shower down there.

Dtp1979

Or craziest of all, install a pump

Sleeper12

It wouldn't even need to be turned off. All it would take is someone using the washing machine, dishwasher or just running the cold tap downstairs and you could scald someone in the shower.
Even if the shower mixer is thermostatic it only works with even hot / cold pressure.
There's a lot to be said for installing a pump. I've a 3 bar Stuart Turner in my hotpress. When sleeping my head is around 12 inches from it on the other side of the wall. It's so quiet I never wake up when it's on

Paul Kiernan

K.Flyer wrote: »

Open the tap slower

You could fit a pressure reducing valve with a pressure gauge, but I think you are wasting your money and effort as 2 - 3 bar is normal on a pressurised system, which is what you will have when its all set up and finished.

The difference is that on a normal pressurised system the pressure remains constant. What I'm getting is extremely high pressure building up when all taps closed but this drops to a trickle after taps are on for about 30 seconds. Adjusting the stopcock affects the rate of this trickle but the pressure build up seems to be the same regardless of how much the stopcock is opened. It's like the mains pressure is bulging out all my supply pipes which then shoot out all the pressurised water when any tap is opened. This happens even if I fully close the stopcock.

K.Flyer

Even with the main stop cock barely open you could get the same symptoms.
As its only a get by for the moment I wouldn't worry about it too much, except to say that you may be having a problem with the mains supply itself.
I presume the final setup will be mains feeding a tank and everything pumped from there?

Dtp1979

Paul Kiernan wrote: »

The difference is that on a normal pressurised system the pressure remains constant. What I'm getting is extremely high pressure building up when all taps closed but this drops to a trickle after taps are on for about 30 seconds. Adjusting the stopcock affects the rate of this trickle but the pressure build up seems to be the same regardless of how much the stopcock is opened. It's like the mains pressure is bulging out all my supply pipes which then shoot out all the pressurised water when any tap is opened. This happens even if I fully close the stopcock.

Have you an expansion vessel on the system on the hot side? What kind of pump have you?

8Choc

Sleeper12 wrote: »

It wouldn't even need to be turned off. All it would take is someone using the washing machine, dishwasher or just running the cold tap downstairs and you could scald someone in the shower.
Even if the shower mixer is thermostatic it only works with even hot / cold pressure.
There's a lot to be said for installing a pump. I've a 3 bar Stuart Turner in my hotpress. When sleeping my head is around 12 inches from it on the other side of the wall. It's so quiet I never wake up when it's on

I suppose one way to run the shower on mains pressure would be to directly connect the cold to mains , fit a flow switch on the hot water pipe - tee the hot water feed to the bottom of the cylinder, so that the cylinder would be fed from both attic tank and mains and then put a solenoid stop valve on the mains feed to the new tee. The flow switch would control the solenoid stop valve (probably through a relay) and the valve would only open when there is hot water flow to the shower. Once the valve opened the shower would have mains pressure on both hot and cold side and thermostatic valve would then operate correctly. If the valve was to fail 'open' the cylinder would overfill and vent up the vent pipe to the attic tank, if it failed closed you'd go back to tank feed on the hot side . No harm done ? The switch,relay and valve would probably cost about 50 quid and ye would never have to buy or run a shower pump.
The only unsafe thing you could do with this whole thing is connect mains to the cylinder and block the vent ? , if the vent pipe is still in place and open there could never be excessive pressure build up etc....

Dtp1979

8Choc wrote: »

I suppose one way to run the shower on mains pressure would be to directly connect the cold to mains , fit a flow switch on the hot water pipe - tee the hot water feed to the bottom of the cylinder, so that the cylinder would be fed from both attic tank and mains and then put a solenoid stop valve on the mains feed to the new tee. The flow switch would control the solenoid stop valve (probably through a relay) and the valve would only open when there is hot water flow to the shower. Once the valve opened the shower would have mains pressure on both hot and cold side and thermostatic valve would then operate correctly. If the valve was to fail 'open' the cylinder would overfill and vent up the vent pipe to the attic tank, if it failed closed you'd go back to tank feed on the hot side . No harm done ? The switch,relay and valve would probably cost about 50 quid and ye would never have to buy or run a shower pump.
The only unsafe thing you could do with this whole thing is connect mains to the cylinder and block the vent ? , if the vent pipe is still in place and open there could never be excessive pressure build up etc....

But the pressure wouldn't be any better because it'd just pour out the vent. You're like a mad scientist version of Andy from Sligo

Sleeper12

8Choc wrote:

I suppose one way to run the shower on mains pressure would be to directly connect the cold to mains , fit a flow switch on the hot water pipe - tee the hot water feed to the bottom of the cylinder, so that the cylinder would be fed from both attic tank and mains and then put a solenoid stop valve on the mains feed to the new tee. The flow switch would control the solenoid stop valve (probably through a relay) and the valve would only open when there is hot water flow to the shower. Once the valve opened the shower would have mains pressure on both hot and cold side and thermostatic valve would then operate correctly. If the valve was to fail 'open' the cylinder would overfill and vent up the vent pipe to the attic tank, if it failed closed you'd go back to tank feed on the hot side . No harm done ? The switch,relay and valve would probably cost about 50 quid and ye would never have to buy or run a shower pump. The only unsafe thing you could do with this whole thing is connect mains to the cylinder and block the vent ? , if the vent pipe is still in place and open there could never be excessive pressure build up etc....

Plumbing has been with us for around 5000 years that we know of. Don't you think if what you wanted was possible that a plumber or engineer would have come up with it before?
You are entertaining if nothing else.

MOD: OP your either joking or your in a real need of a good plumber either way I'm closing this silliness