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Shower boosting pump help!

Hi Guys, any help or advice would be appreciated.

I recently had an old salamander shower pump replaced and its not performing as well as the original.

Previous pump was a Salamander RIght RSP 50 (centrifugal)

Quoted flows:
10 lpm @ 1.3 bar
20 lpm @1.2 bar
Max 1.5 bar

Current equivalent / replacement for that from Salamander is RP50PT, according to their own site.

They have installed a CTForce 20 TU, stating that there was not enough height between water tank and upstairs shower head. They did not look or ask for any measurements. The drop from the bottom of the upstairs water tank to the upstairs shower head is about 670mm. Spec of the RP50PT (and the previous RSP 50 said 600mm minimum, and it always was enough to trigger the pump.

Quoted flows:
8 lpm @ 1.8 bar
16 lpm @ 1.5 bar
Max 2.0 bar

A 5 litre bucket takes about 18 seconds to fill from the downstairs shower
The same bucket takes about 35 seconds to fill at the upstairs one.

Now the flow rates are not bad but if i were getting a replacement pump i would want the pressure & flow to match the original installation and its the upstairs shower where the issue is.

Also to add the hot water tank and pump is located in a store adjacent to the ground floor shower and the first floor shower is directly above (minimal pipe runs). I have attached a picture of the new pump installation.

Is the pump that has been recommended correct or is it a lower spec pump?


Shower pump.jpg
Downstairs shower off the same pump ?
Yes, branched off at shower head height.
Yes, branched off at shower head height.
I've compared the two pump curves at the original pump has a much higher flow rate at lower pressures. The shower pump can only be about 5m from pump the FF shower head. equaling a pressure to over come of 0.5bar.
Last edited:


Staff member
S. Mod
Gas Engineer
Have you cleaned the filters for the upstairs shower as I don’t think it’s a pump fault

Your running one shower at a time correct ?
Hello, just to make you aware that the original pump was a centrifugal pump, whereas the current pump is a regenerative style pump. Centrifugal pumps will deliver a deliver higher flow rates at equivalent pressures given the make up of the impeller.