Apologies for a long-winded story but I am attempting to install a pump to boost a shower, without complete success. Any suggestions to help me achieve a satisfactory solution will be greatly appreciated. The situation so far:
With the pump running and the shower mixer temperature selector set to ‘maximum heat’ the water delivered at the shower head starts at barely warm then gradually gets cooler, as if the cold water slowly overpowers the hot water arriving at the mixer.
I have installed the pump on the floor next to the hot cylinder in the airing cupboard.
The 22mm cold feed drops from the storage tank (in the loft and directly above the airing cupboard) into the pump.
From the pump the load side rises and crosses the loft in 22mm until just before it drops to the shower mixer in 15mm. This loft section of the run is approximately 6 metres long and the pressure is fine at the shower head with the pump running (also quite good without).
For the hot water it may give more of an idea if I first describe the original pipe installation. A 22mm leaves the top of the cylinder and rises vertically for 9 inches. It turns at a right angle toward the back wall and connects into a T junction (expansion pipe rising and hot water supply falling). 6 inches below this T is another T where the old gravity feed was taken to the shower via an under the floor route, but I need to divert it ‘up and over’ for various reasons.
At my first attempt I cut away the section disappearing under the floor, fitted an isolation valve and connected to the supply side of the pump (in 22mm). I then followed the same route as the cold water run from the pump, up and across the loft, again reducing to 15mm where it drops to the shower mixer.
On use I discovered the problem of the ‘barely warm’ shower gradually getting colder. Thinking the numerous angles in the run may be giving excess resistance I sealed off this original pickup point and changed it. I have cut a T junction into the 9 inch vertical section of the pipe directly above the exit from the cylinder. I fitted an isolation valve into the new horizontal section of pipe and just after this turned at a right angle down to the supply side of the pump.
There is no improvement at the shower head at all !. Still ‘barely warm’ and slowly getting cold !!!
Now I have an added problem. I not only get air in the system but, with the shower off, when I close any hot water tap after drawing off water the pump springs into life for just a couple of seconds.
Have I now created a ‘siphoning effect’ when drawing hot water from a tap, that diverts to the pump circuit when the tap is suddenly closed ?. HELP !.
I have reached the stage where I am considering going back to the drawing board and trying the following. Because the gravity feed on the cold is quite healthy, should I just run a 22mm across the loft from the tank to the shower and fit a ‘not too powerful’ pump on the hot water to boost it ?
Your suggestions and advice will be greatly appreciated greatly
Kind regards
With the pump running and the shower mixer temperature selector set to ‘maximum heat’ the water delivered at the shower head starts at barely warm then gradually gets cooler, as if the cold water slowly overpowers the hot water arriving at the mixer.
I have installed the pump on the floor next to the hot cylinder in the airing cupboard.
The 22mm cold feed drops from the storage tank (in the loft and directly above the airing cupboard) into the pump.
From the pump the load side rises and crosses the loft in 22mm until just before it drops to the shower mixer in 15mm. This loft section of the run is approximately 6 metres long and the pressure is fine at the shower head with the pump running (also quite good without).
For the hot water it may give more of an idea if I first describe the original pipe installation. A 22mm leaves the top of the cylinder and rises vertically for 9 inches. It turns at a right angle toward the back wall and connects into a T junction (expansion pipe rising and hot water supply falling). 6 inches below this T is another T where the old gravity feed was taken to the shower via an under the floor route, but I need to divert it ‘up and over’ for various reasons.
At my first attempt I cut away the section disappearing under the floor, fitted an isolation valve and connected to the supply side of the pump (in 22mm). I then followed the same route as the cold water run from the pump, up and across the loft, again reducing to 15mm where it drops to the shower mixer.
On use I discovered the problem of the ‘barely warm’ shower gradually getting colder. Thinking the numerous angles in the run may be giving excess resistance I sealed off this original pickup point and changed it. I have cut a T junction into the 9 inch vertical section of the pipe directly above the exit from the cylinder. I fitted an isolation valve into the new horizontal section of pipe and just after this turned at a right angle down to the supply side of the pump.
There is no improvement at the shower head at all !. Still ‘barely warm’ and slowly getting cold !!!
Now I have an added problem. I not only get air in the system but, with the shower off, when I close any hot water tap after drawing off water the pump springs into life for just a couple of seconds.
Have I now created a ‘siphoning effect’ when drawing hot water from a tap, that diverts to the pump circuit when the tap is suddenly closed ?. HELP !.
I have reached the stage where I am considering going back to the drawing board and trying the following. Because the gravity feed on the cold is quite healthy, should I just run a 22mm across the loft from the tank to the shower and fit a ‘not too powerful’ pump on the hot water to boost it ?
Your suggestions and advice will be greatly appreciated greatly
Kind regards
