A plumbing question - shower pump fitting!
Discussion
I'm fitting a shower pump to serve 2 showers (3.3bar).
The pipework is already in place.
I just need to tee into the supply pipes to each shower for both HW and CW.
The water tank is in the loft about 6 feet above the top of the hot water cylinder, the shower pump will be fitted in the same cupboard as the hot water cylinder and will sit on the floor.
The supply pipes are configured as follows:-
Cold water supply to each shower comes down from tank in loft, through cupboard with hot water cylinder and goes under the floor and to the showers and the hot water pipes to each shower go from cylinder up the inside of the cupboard and through the loft and down again to each shower (still about 2ft below the water storage tank in the loft - so still a positive head).
The route of the hot water pipes is stupid I know as it reduces the head of pressure on the hot supply compared to the easier route of the cold supplies. Resulting in a bias to cold water at each shower mixer.
I can't really run new hot water pipes alongside the cold ones as this would be major works running pipework underfloor, so I'm going with what I have already.
I'm not very clued up on this I guess and I wonder whether there is anything I need to do such as fitting an Essex or Surrey flange in the hot water tank?
Is it possible that I may get any cavitation with the pipework confiuration that I have described?
The pipework is already in place.
I just need to tee into the supply pipes to each shower for both HW and CW.
The water tank is in the loft about 6 feet above the top of the hot water cylinder, the shower pump will be fitted in the same cupboard as the hot water cylinder and will sit on the floor.
The supply pipes are configured as follows:-
Cold water supply to each shower comes down from tank in loft, through cupboard with hot water cylinder and goes under the floor and to the showers and the hot water pipes to each shower go from cylinder up the inside of the cupboard and through the loft and down again to each shower (still about 2ft below the water storage tank in the loft - so still a positive head).
The route of the hot water pipes is stupid I know as it reduces the head of pressure on the hot supply compared to the easier route of the cold supplies. Resulting in a bias to cold water at each shower mixer.
I can't really run new hot water pipes alongside the cold ones as this would be major works running pipework underfloor, so I'm going with what I have already.
I'm not very clued up on this I guess and I wonder whether there is anything I need to do such as fitting an Essex or Surrey flange in the hot water tank?
Is it possible that I may get any cavitation with the pipework confiuration that I have described?
sniggerfulham911club said:
Not just to state the obvious but have you tried calling a plumber ... otherwise I'm not sure you'll get a straight answer here, its Friday and too many flanges
I've tried 4 plumbers over the past 9-10 months.
I managed to get one round to quote but actually trying to get any back to do the job seems impossible!
I've recently tried calling others who have said they can quote me but not actually do the job for another 6-12 months.
I eventually found one who was going to come and do it but he didn't turn up then eventually told me had taken on too much work!
Hence I've given up and will have a go myself.
Just need to know why & whether I need one of these pesky surrey or essex flanges!
>> Edited by Kentish on Friday 7th October 13:37
Shouldn't the pump sort out any pressure differences between hot and cold?As long as the input pressure to the pump is within that on the spec sheet I would expect it to be OK.We have a bungalow,the pump for the shower is ,like yours, on the floor of the Cupboard with the hot water tank in,and the cold tank is in the loft.If I remember correctly I just teed it off the main hot water pipe out of the tank and just added a new pipe to the cold water tank.I suppose I could have used the rising main with a pressure reducer for the cold supply but it was easier to do it as I have..We have no probs at all (except we live in a hard water area and I have fitted filters to the supply side of the pump which need cleaning out fairly frequently)Hope this helps.
>> Edited by esselte on Friday 7th October 13:41
>> Edited by esselte on Friday 7th October 13:41
esselte said:
Shouldn't the pump sort out any pressure differences between hot and cold?As long as the input pressure to the pump is within that on the spec sheet I would expect it to be OK.We have a bungalow,the pump for the shower is ,like yours, on the floor of the Cupboard with the hot water tank in,and the cold tank is in the loft.We have no probs at all (except we live in a hard water area and I have fitted filters to the supply side of the pump which need cleaning out fairly frequently)Hope this helps.
Thanks, I am inclined to agree that as long as supply (loft tank) is of sufficient capacity and there is a positive head there shouldn't be any problems if I site the pump below both loft tank an hot water cylinder.
I googled the flanges but didn't really give me any better idea of when you need to use them.
If you just tap into the hot water pipe there is a risk that you will suck up air bubbles - which knacker pumps. A flange goes into the HW cylinder, either at the top or in one side, and takes the water from lower down, thus avoiding air bubbles. Follow the instructions that came with the pump, or call the makers and ask which flange/s they recommend.
Every layout you could imagine here: http://images.google.co.uk/images?q=essex+flange&hl=en
>> Edited by simpo two on Friday 7th October 13:54
Every layout you could imagine here: http://images.google.co.uk/images?q=essex+flange&hl=en
>> Edited by simpo two on Friday 7th October 13:54
I put the hole in the cold tank fairly near the bottom (but not too near to avoid any silt coming doen the pipe into the pump.So long as the flow rate into your cold tank is adequate then you should be OK.(Although I am not a plumber and some professional type may be able to corrrect me!)
simpo two said:
If you just tap into the hot water pipe there is a risk that you will suck up air bubbles - which knacker pumps. A flange goes into the HW cylinder, either at the top or in one side, and takes the water from lower down, thus avoiding air bubbles. Follow the instructions that came with the pump, or call the makers and ask which flange/s they recommend.
Quite possibly,but I've had mine in for 5 years now(ooer) and had no probs.
simpo two said:
If you just tap into the hot water pipe there is a risk that you will suck up air bubbles - which knacker pumps. A flange goes into the HW cylinder, either at the top or in one side, and takes the water from lower down, thus avoiding air bubbles. Follow the instructions that came with the pump, or call the makers and ask which flange/s they recommend.
Thanks ST.
I'll check where the pipes come from the cylinder and if it's low I should be OK without. If not low I'll make sure I fit one.
Cheers
Hi Did this last year so the answers are:-
1. The pressure should be similar since the pressure is set by the height of the header tank not the hot water tank. Distance should not make a difference but lots of right angle bends can restrict flow so best to avoid these.
2. Hope you used 22mm pipe??
3. You need an Essex Flange to connect pipe work to the hot water tank. This sounds tricky but it is not. Drain the water. Drill into the tank on the side, instructions will say how far down. The Flange is difficult to describe but its not hard if a fiddly. Mine came with full instructions.
1. The pressure should be similar since the pressure is set by the height of the header tank not the hot water tank. Distance should not make a difference but lots of right angle bends can restrict flow so best to avoid these.
2. Hope you used 22mm pipe??
3. You need an Essex Flange to connect pipe work to the hot water tank. This sounds tricky but it is not. Drain the water. Drill into the tank on the side, instructions will say how far down. The Flange is difficult to describe but its not hard if a fiddly. Mine came with full instructions.
Kentish said:
I'll check where the pipes come from the cylinder and if it's low I should be OK without. If not low I'll make sure I fit one.
Yep but the lower it is, the less hot the water will be
My shower/pump is by Aqualisa - my friendly plumbing shop rang them up and asked what flange to use. Do check with the pump makers because if the pump breaks and you claim on warranty, it might be void if you use the wrong flange.
>> Edited by simpo two on Friday 7th October 14:00
simpo two said:
I'll check where the pipes come from the cylinder and if it's low I should be OK without. If not low I'll make sure I fit one.
Yep but the lower it is, the less hot the water will be
My shower/pump is by Aqualisa - my friendly plumbing shop rang them up and asked what flange to use. Do check with the pump makers because if the pump breaks and you claim on warranty, it might be void if you use the wrong flange.
>> Edited by simpo two on Friday 7th October 14:00
Okey dokey, will do.
Not worth "not" fitting one for sake of £15, just a bit more work
Thanks for the advice all.
Gassing Station | The Pie & Piston Archive | Top of Page | What's New | My Stuff