Pump for HW

[Crakkers]

Hello,

I have poor hot water pressure and I am considering using a pump to increase flow. I have seen the Stuart Turner Techflo TP S Positive Head Shower Pumps 1.5bar & 2.0 bar.

I have a conventional open vent system with tank and cylinder in the loft. The tank sits directly on top of the cylinder, hence the poor pressure.

I am considering fitting the pump in the loft on a horizontal hw pipe after the vent and before it decends into the bathroom.

Would this be appropriate and a satisfactory place to fit the pump?

Any good advice appreciated

Thanks

 

[stem]

The location will depend upon the manufacturer's instructions, but it is usual to sit the pump on the floor at the side of the hot water cylinder, something like this.

Untitled

• stem
• 1 Feb 2011
• 5

This is for several reasons. Firstly, air that collects at the top of the hot water cylinder as the water is heated, is allowed to vent upwards and away from the inlet to the pump so that the air is not sucked into it. Air in the pump can cause cavitation and failure to pump properly. Secondly most pumps need a 'positive head' to feed them, so even though there may be not a lot of pressure presently, the pump needs a good water flow that it can boost the pressure of. This sometimes means using 22mm pipe directly from the cylinder to the pump. Having said that, negative head pumps are available that can be located higher up, but are more complex and expensive.

The image shown above is for a hot and cold boost and is the type used for a power shower where both stored supplies of hot and cold water are used simultaneously. If you want to boost the hot water supply to all of the outlets in the bathroom, then you can get a single impeller type just for the hot water. However, the above still applies.

Bear in mind that these pumps can be noisy and if loft mounted will likely wake up any sleepers when used.

 

[Crakkers]

Stem,

Thank you for your reply. I take the point about the noise...........so "silent" pumps are not exactly silent then?

 

[muggles]

Nothing is silent, but good quality pumps will at least be quiet. The pump you've suggested might be insufficient to run more than one outlet at once, as that's all it's really designed for.

 

[Crakkers]

Nothing is silent, but good quality pumps will at least be quiet.

Thanks, can you suggest a good one?

Thanks

C

 

[muggles]

Stuart Turner pumps are arguably the best, but you'd be better off looking at the Monsoon or Monsoon Extra range for whole-house applications. How big is your loft tank?

 

[Crakkers]

Stuart Turner pumps are arguably the best, but you'd be better off looking at the Monsoon or Monsoon Extra range for whole-house applications. How big is your loft tank?

Dunno, Maybe 40 gals? Should I have a minimum size tank?

 

[muggles]

You should bear in mind that a pump will drain your tank faster than usual, so the tank needs to be checked for size according to the expected higher demand. If a pump is pumping at 30 litres a minute, a 40 gallon tank will be empty in six minutes