Good catch. To quote the Stuart Turner installation manual:
"The cold water supply: Must be a DEDICATED AIR FREE supply via a tank connector, and must be positioned at a slightly lower level (25 mm minimum) than the feed pipe to the hot water cylinder."
I've always assumed that the "25mm lower" requirement is for safety; to mitigate a scalding hazard by ensuring that, if the CW store is starved, the hot feed to the pump is exhausted before the cold feed runs out. The Salamander CT installation guide, however, doesn't seem to include this requirement and the diagrams are inconsistent on this point.
Thankyou for this information.
So I went and took another look at my neighbours shower pump etc and apologies my eyes worked better today and I made a mistake on the pipework. I think the pipework is ok as per below, if I'm wrong please let me know
Here is what I originally reported
"The bigger pipework comes down into her hot water tank cupboard and goes into this tank near the bottom. Just before the tank it does joint off to a slightly smaller pipe that goes into the shower pump. There is a blue rubber handle on it which guessing is to stop the flow as there is one on the opposite pipe coming out the other side of the shower pump, which has 4 connections in all. These 2 blue ones and another 2 red handled ones."
The big main pipe has a blue handle valve on it, soon after that it the big pipe runs along the back wall and goes into the hot water tank down the bottom rear of it, and it also joints or tees off to that slightly smaller pipe I noticed.
I wrongly traced this pipe before and thought it went into the pump as it runs behind this pump and there is a lot of pipework in the cupboard at this point.
It doesn't connect into the pump, this little pipe joining off of the big cold tank pipe ends in what I know is a bleed valve to drain with a hose as my plumber has done it around mine before when replacing something.
It does not go into the shower pump. Sorry. The pipe ends in a bleed valve tucked behind the pump.
Looking properly at all the pipes this time and squiggling some down on paper, the shower pump has its own smaller pipe feed coming down the wall into it from the cold tank, there is smudged marker pen on it but it looks like it might once have said "CWT to Pump". I went into the loft and confirmed there were 2 different pipes coming down also.
The shower pump then has its other cold pipe going up to the shower, both of these cold pipes run side by side up the wall. Both have blue shut off handles soon after the pump.
The shower pump then has a hot pipe coming to it from out of the top of the Hot water tank and it goes into the pump, then the pumps other hot pipe goes up the wall next to the cold pipes going down from the cold tank and up to the shower.
The shower pump sits on the floor of the cupboard and according to its metal plate information it is a Monsoon Standard Twin 2.0 pump, I searched a bit and I believe it is a pump providing 2 bars of pressure to her existing shower?
As it sits on the floor and you mentioned some measurements I took a tape over. The pump is on the floor and has heavy duty flexicoil pipes which connect to the pipes on the wall/from the tank, where each flexicoil goes into the pump it measures about 400 - 420mm from the floor.
The hot pipe feed coming out of the hot tank is approx 1120mm in height from the floor and it runs shortly to a wall and then clips around the back wall of the cupboard at this height. It then comes down the back wall corner to a height of around 520mm and then comes over and around the cupboards sidewall (this sidewall has the majority of the pipework on it) where it then connects to one of the heavy duty flexicoils into the pump, and they all connect into the pump at around 400 - 420mm height.
Is that sort of in line with the 25mm you mentioned please?
Again sorry for the mistake but also I have enjoyed learning on this thread. Thankyou for your time and patience.
