Fitting a whole house pump?

Andy From Sligo

I reckon in the future I will need to fit a whole house pump to the header tank because the low pressure in basins and filling up of toilet cisterns is very weak ... but with so many outlets of the bottom of the header tank how can I fit one pump to do all the outlets - Im confused
heres a little diagram of my setup - done in my usual 90's mspaint style

TPM

Andy From Sligo wrote: »

I reckon in the future I will need to fit a whole house pump to the header tank because the low pressure in basins and filling up of toilet cisterns is very weak ... but with so many outlets of the bottom of the header tank how can I fit one pump to do all the outlets - Im confused
heres a little diagram of my setup - done in my usual 90's mspaint style

you take 1 outlet from the tank to the pump, blank off the other outlets, then you connect the pipes that were previously connected to the tank to the pump outlet

Andy From Sligo

TPM wrote: »

you take 1 outlet from the tank to the pump, blank off the other outlets, then you connect the pipes that were previously connected to the tank to the pump outlet

Thank you for answering - If I do that, if someone in shower and they pull toilet chain or use tap in downstairs bathroom coming from header tank will cold water to shower be affected? - one shower is 8.5kw instantaneous and the other shower is hot(from immersion cylinder)& cold feed (but I think its thermostatic controlled so maybe it not an issue)

Simarly if someone runs hot water and the immersion tank is filling up with this alter temp in showers? - I thought this is why they all have their own seperate feeds from the bottom of the header tank and dont come out of all one pipe?

TPM

Andy From Sligo wrote: »

Thank you for answering - If I do that, if someone in shower and they pull toilet chain or use tap in downstairs bathroom coming from header tank will cold water to shower be affected?

not if the pump is correctly sized

Andy From Sligo wrote: »

one shower is 8.5kw instantaneous

that will be a gravity feed shower and will have to remain connect to the attic tank

Andy From Sligo wrote: »

other shower is hot(from immersion cylinder)& cold feed (but I think its thermostatic controlled so maybe it not an issue)

the hot will need to be pressurised also if you have a suitable cylinder you can feed it with the pressurised cold and a pressurisation kit (fit expansion vessel pressure reducing valve safety valve etc.) if its a copper cyliinder and you dont want to change it you will need to leave it gravity feed and fit a pump on the hot side.

Andy From Sligo wrote: »

Simarly if someone runs hot water and the immersion tank is filling up with this alter temp in showers? - I thought this is why they all have their own seperate feeds from the bottom of the header tank and dont come out of all one pipe?

on a gravity system if more than one point on the same pipe is open at same time the flow will drop significantly, but not so much on a pressurised system.

Andy From Sligo

TPM wrote: »

not if the pump is correctly sized


that will be a gravity feed shower and will have to remain connect to the attic tank


the hot will need to be pressurised also if you have a suitable cylinder you can feed it with the pressurised cold and a pressurisation kit (fit expansion vessel pressure reducing valve safety valve etc.) if its a copper cyliinder and you dont want to change it you will need to leave it gravity feed and fit a pump on the hot side.



on a gravity system if more than one point on the same pipe is open at same time the flow will drop significantly, but not so much on a pressurised system.

ah right, thank you for your replies and help. - sounds a bit more in depth than I thought.

its just a normal immersion cylinder - so does that mean the cold inlet on the cylinder cannot be fed from the pump up in the loft at the header tank then? would it just pump into the expansion pipe of the cylinder and into the header tank?

Would this work:

K.Flyer

No, because the cylinder in your diagram is open-vented.
Using TPM's method you will also need to change the cylinder to a stainless steel un-vented model, so costs will ramp up considerably.
Simple method would be as follows.
Buy a Stuart Turner 3 Bar Twin Brass Impeller Pump.
Fit it in the hot press beside the cylinder.
Using a Warix flange and adjusting pipework on the cylinder draw hot water from the cylinder to one side of the pump and back to existing hot water supply pipework.
Presuming main cold supply from tank goes to a valve in the hot press first. Arrange pipework after this valve to the pump and back to existing cold water supply pipework, with a branch feeding to the cold supply pipe for the gravity shower which you will have disconnected from the attic tank.
Existing instantaneous shower pipework remains as is, everything else is now sufficiently pressurised.

antoinolachtnai

That is good advice you have there from K.Flyer.

The problem with your diagram is that water will pour out of the the open vent, because of the pressure created by the pump. This will create an intensely educational and entertaining fountain in your attic but the water will not heat!

Tom44

Andy ?


Surely to God you inspect houses before you move in ?















And confirm they have adequate insurance too.

Andy From Sligo

Tom44 wrote: »

Andy ?


Surely to God you inspect houses before you move in ?



And confirm they have adequate insurance too.

hello Tom - how ya doing

Andy From Sligo

thanks all for your input and advice - when i comes to it, I will call in a professional to install it , I wont be tackling it myself but it will be great to have this knowledge beforehand.

Do you reckon the whole upgrade including pump and labour will come to more than 250eur (am I being unrealistic because some pumps can cost that and more alone cant they?)

- I know you cannot say for certain and I suppose it depends whats involved in job and how long plumber here for but are there any ball park price at how much roughly it would costs to put a pump on my type of system?

antoinolachtnai

K.Flyer will know better than me but yes you are being totally unrealistic. The pump alone will cost more than that (maybe triple, though you can get them for a good bit less in the UK for some reason). Install depends on what the plumbing looks like, but it could be done in a day or a day and a bit I suppose if your hot water cylinder is easily accessible from the cold tank and there is plenty room up there. Also, you'd need to be sure your tanks were big enough to cope with the increased flow. Upgrading tanks will add a good bit to the cost. And then, you need to be sure you have the heating capacity to heat the water needed.

One other thing you could consider doing, and it might be feasible, is to raise the level of the water tank in the attic.

K.Flyer

Andy From Sligo wrote: »

Do you reckon the whole upgrade including pump and labour will come to more than 250eur (am I being unrealistic because some pumps can cost that and more alone cant they?)

It really depends on how accessible pipework is, space available, electric connection etc, for example, for a 2 bar positive head pump you could easily be getting close to 900 euro all in, maybe more.
As Antoinolachtnai says, you also need to look at your water storage capacity as the pump will use a lot of water in a shorter time.

Andy From Sligo

ooh blimey , sounds like I be better putting up with pressure I have got then. Its not like trickling out of the taps, but then again it would be lovely to have some more pressure to fill up toilet cisterns quicker and basins and bath fill up quicker and washing up bowl quicker .... but not to that extent/expense

Tom44

Taps filling sinks don't take forever.
Taps filling bath's dont take forever.
Anyway, you can kill some time about how to improve the neighbours house.
Toilet ballcock / filling device, can be adjusted to fill quickly at low pressure.
You have a pumped electric shower.

You dont have a problem, ........... I think