Hot water recirculation is found in some larger homes and is driven by a low flow low head single impeller pump. In such circumstances it is difficult to boost the flow and pressure because if you simply install a more powerful recirculation pump you simply speed up the recirculation.
SP21S To Boost all Recirculation Loops
A SP21S is a two pump pack consisting of and automatic and a slave pump.

SP21S £155
The automatic Shower Power Booster can be fitted in line with the existing recirculation pump to provide a high pressure boost. With the existing recirculation pump running, reduce the return flow to below 1.2 litres a minute. You may take this opportunity to replace the existing recirculation pump with a WrightChoice V1 Radiator Booster.
Fit the slave Shower Power Booster to oppose the return flow.
When any shower or tap is turned on, the automatic Shower Power Booster will detect a flow greater that 1.2 litres a minute, and both it and the slave pump will turn on.

Shower Power Boosters can Boost Hot Water Recirculation
Any high points in the system needs to be vented and if it is not practical to connect the pipes into the vent pipe then fit air valves on the high points.

15mm Automatic Air Vent
As an alternative to boosting the full loop you can boost closer to the tap or shower and boost just that tap or shower.

Shower Power Boosters can Boost Hot Water Recirculation

SP2B Fully Automatic
Shower Power Booster

