Adding a booster pump to a secondary system

[SmithO]

Hi, thanks for reading post.

I’m working in a large house which has 3 upstairs bathrooms all with showers and baths. Hot water pressure is very poor so looking to add a booster pump to the hot side. Cold is taken from mains to all bathrooms.

Have added booster pump to system and turned off secondary system pump and valves so no hot water should be returning back to cylinder. But the pump is constantly on and pressure indicator on cylinder is showing large fluctuations. Struggling to trouble shoot why water still returning back to cylinder.

System is quite old so could secondary system valves be perished? There is one immediately before and after the brass pump?

Any advice greatly appreciated. I have a small building contract company, and customer wants us to increase hot pressure.

Many thanks.

 

[Riley]

My advice would be get G3 qualified engineer in after the festive period as this isn’t fixed just with a pump in fact you are exacerbating the problem and using up hot water even quicker. There’s much more to it

 

[SmithO]

That is the plan inevitably Riley. Just needed to see if can get pressure for bathrooms in the short term. (Showers etc.)

 

[Riley]

I would advise them that there is no quick fix

 

[JVTrades]

This is the comment I made earlier. Sometimes the only option is an expensive one. What is the pressure both static and dynamic? you need this info before you know if unvented is viable and recorded at different times of day and especially at times of high usage in the area. You may need an accumulator too. The answer can be quite complex and there are lots of things to take into consideration that may not be obvious to none plumbers. The hot water has been under gravity for years and then you are pressurising it and this can lead to problems not caused by but exposing issues that have been there for ages.

 

[SmithO]

Thanks JV