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May 11, 2022
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maidstone
Member Type
DIY or Homeowner
I Cannot installa unvented cyclinder because my waterflow rate is too low.
I am therefore thinking of using the old attic tank feeding a cylinder system.
My query is, Which is the better of two cylinder placements. Water fed to a cylinder in the loft with hot water fed from top of cylinder DROPPING
down the cylinder height to shower level ,or
Placing the cylinder on the froor below (8ft) and having the water RISE to the shower height of 7ft
 
The force of the shower is fundamentally determined by the height your cold water storage tank is above the shower nozzle. You want the biggest distance you can muster (or add a pump!)
Where you put the hot water cylinder won't have an effect on the head, so above or below the shower won't make much difference. Further away wastes water, as it takes longer to run hot through to the shower.
As above, I wouldn't put one in the loft, and given the insulation is not 100% effective, you might as well have the warmth in the house rather than the Loft!

Our cold water tank is supported on a platform in the attic, and the bathroom is on the floor immediately below. But the hot water cylinder is at the other end of the house. All shower feeds are in 22mm, and our old Aqualisa low pressure thermostatic mixer produces an excellent shower - It just takes several minutes before the hot water comes through!!
 
The force of the shower is fundamentally determined by the height your cold water storage tank is above the shower nozzle. You want the biggest distance you can muster (or add a pump!)
Where you put the hot water cylinder won't have an effect on the head, so above or below the shower won't make much difference. Further away wastes water, as it takes longer to run hot through to the shower.
As above, I wouldn't put one in the loft, and given the insulation is not 100% effective, you might as well have the warmth in the house rather than the Loft!

Our cold water tank is supported on a platform in the attic, and the bathroom is on the floor immediately below. But the hot water cylinder is at the other end of the house. All shower feeds are in 22mm, and our old Aqualisa low pressure thermostatic mixer produces an excellent shower - It just takes several minutes before the hot water comes through!!
Thanks for your explanaton Basher, I am aware of the conventional method but I just wondered. whether there was an apreciable difference betwen the water dropping to the shower (with gravity) or having to rise to the shower head. Thanks again
 
As badger says, none whatsoever.
The reasons not to have in the loft are; heat loss, maintenance, spotting if there is a problem, all these are also relevant to a shower pump - which wants to really be at the base of the cylinder.
 
I just wondered. whether there was an apreciable difference betwen the water dropping to the shower (with gravity) or having to rise to the shower head.
As above, it may sound counter-intuitive, but the only effect in operation is the resistance of the pipework, as as long as the bore is appropriate for the job, that effect will be negligible .
Say you put the cylinder on the floor by the shower, the distance from the surface of the water in the cold water storage tank in the attic to where that water goes into the cylinder, is counteracted by the distance between that entry point and back up to the shower head, i.e. the "down" section is balanced by the "up" section.
So you end up with the same pressure coming out of the shower, whether you put the hot water cylinder in the attic or in the basement!
 
As above, it may sound counter-intuitive, but the only effect in operation is the resistance of the pipework, as as long as the bore is appropriate for the job, that effect will be negligible .
Say you put the cylinder on the floor by the shower, the distance from the surface of the water in the cold water storage tank in the attic to where that water goes into the cylinder, is counteracted by the distance between that entry point and back up to the shower head, i.e. the "down" section is balanced by the "up" section.
So you end up with the same pressure coming out of the shower, whether you put the hot water cylinder in the attic or in the basement!
 

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