Adam Treen, Operations Manager, Grundfos. provides a guide on how installers can help customers improve their shower experiences.
Q. Grundfos supplies Shower Pumps for both Positive and Universal heads. What is the difference between these and how can installers calculate which version is required for an installation?
A Universal pump should be installed when the outlet (let’s say a shower head) is less than 250mm in vertical distance from the exit of the cold-water storage tank. The condition exists where the flow from the outlet is less than 0.5 litre/minute. Typically, this is where insufficient pressure, under gravity, can provide flow to the outlet. A classic example is where a loft has been converted with an en-suite and the cold-water storage tank is then not higher than the outlet of the en-suite shower.
A positive shower pump is therefore where there is more than 0.5 litre/minute of flow from the outlet.
In pump performance, 1.0 Bar is generally considered low pressure, 1.5-2 Bar is medium pressure and greater than 3.0 Bar high pressure. E.g. to run multiple showers / heads.
Q. Do you offer any help to plumbers requiring assistance in selecting the correct Shower Pump for an installation?
Help is always at hand for installers to make the right decision about which pump to choose. For general information on the range of Grundfos products check out our main site, where you can also find a helpful shower pump selector, which will direct the more knowledgeable individual to the correct pump.
Q. For instance, which Shower Pump would be most suitable to boost the shower in both a family bathroom and an e-suite?
Once identifying the install as either a positive or universal scenario the most suitable product for this would be a 2 Bar composite or brass pump. The selection of either of these is then down to budget, where the premium more robust brass pump will offer longevity and the composite STR2 is suited to space constrained environments.
Q. Where is the best place to install a Shower Pump?
A shower pump should be sited as close to the hot water cylinder as possible, however if the shower pump is fitted in the loft or above a hot water cylinder minimum static head is required 0.5 litres/minute.
Q. Do Grundfos Shower Pumps overcome any air pockets that may be in the system?
To minimise air pockets within the system we would recommend the installation of a surrey flange to the hot water cylinder. All Grundfos shower pumps are designed to minimise water turbulence within the pump head and therefore overcome air pockets issues commonly encountered in centrifugal style shower pump designs.
Q. Are connection hoses included?
All Grundfos shower pumps are supplied with high quality braided hoses with minimal bore reduction that can influence water flow to the outlet.
Q. Does the company’s Shower Pumps confirm to WRAS UK approval?
Grundfos shower pumps have all been WRAS approved, and all shower pumps have been 100% tested for performance, prior to leaving the UK factory.