Hi all
I have just had a plumber install a Grundfos 4.5 bar Home Booster, and I’m not convinced it is working as it should be. The flow and outlet pressure seem to drop off significantly as I turn on multiple outlets (bath tap, shower, basin tap). My understanding is that the Home Booster should maintain the pressure at the PRV setting and is designed to prevent loss of pressure and flow, even with multiple outlets open?
The PRV on the discharge pipework is set to 3.0 bar and the plumber has put a pressure gauge downstream of the PRV.
I have checked the pre-charge pressure and it is around 3.5 bar (slightly higher than the 3.15 bar I think it should be set to according to the manual).
The unit pressurises up to around 5.5 bar in a no flow condition, and the pump cuts-in as it should at 3.5 bar.
I’ve carried out some tests to see the effect of opening various outlets on the outlet pressure gauge and used a flow meter to measure the flow rate at the outlet. As you can see with three outlets open the pressure on the gauge drops from 3.0 bar to 1.6 bar, and the flow rate at the some outlets also decreases by up to 50%.
Basin tap open – pressure on gauge drops from 3.0 bar to 2.2 bar, flow rate 10l/min
Basin tap and shower (with head removed) open - pressure on gauge drops to 1.8 bar, flow rate @ basin tap 8l/min, @ shower 10 l/min
Basin tap, shower (with head removed), and bath tap open. Pressure on gauge drops to 1.6 bar, flow rate @ basin tap 5l/min, @ shower 8 l/min, @ bath tap 10 l/min.
We are currently having a second en-suite shower installed, so I’m expecting that we may have issues running both showers at the same time when the new shower is up and running.
My plumber doesn’t seem to have any answers, and I’m waiting for Grundfos technical support for a reply to a query I have sent them.
Does anyone have any ideas why the pressure and flow rates would drop off so significantly? I was expecting that the Home Booster would gives us a dynamic pressure just under 3.0 bar (PRV setting) and be able to maintain high flow rates across multiple outlets, but this dosen’t seem to be the case.
Many thanks
I have just had a plumber install a Grundfos 4.5 bar Home Booster, and I’m not convinced it is working as it should be. The flow and outlet pressure seem to drop off significantly as I turn on multiple outlets (bath tap, shower, basin tap). My understanding is that the Home Booster should maintain the pressure at the PRV setting and is designed to prevent loss of pressure and flow, even with multiple outlets open?
The PRV on the discharge pipework is set to 3.0 bar and the plumber has put a pressure gauge downstream of the PRV.
I have checked the pre-charge pressure and it is around 3.5 bar (slightly higher than the 3.15 bar I think it should be set to according to the manual).
The unit pressurises up to around 5.5 bar in a no flow condition, and the pump cuts-in as it should at 3.5 bar.
I’ve carried out some tests to see the effect of opening various outlets on the outlet pressure gauge and used a flow meter to measure the flow rate at the outlet. As you can see with three outlets open the pressure on the gauge drops from 3.0 bar to 1.6 bar, and the flow rate at the some outlets also decreases by up to 50%.
Basin tap open – pressure on gauge drops from 3.0 bar to 2.2 bar, flow rate 10l/min
Basin tap and shower (with head removed) open - pressure on gauge drops to 1.8 bar, flow rate @ basin tap 8l/min, @ shower 10 l/min
Basin tap, shower (with head removed), and bath tap open. Pressure on gauge drops to 1.6 bar, flow rate @ basin tap 5l/min, @ shower 8 l/min, @ bath tap 10 l/min.
We are currently having a second en-suite shower installed, so I’m expecting that we may have issues running both showers at the same time when the new shower is up and running.
My plumber doesn’t seem to have any answers, and I’m waiting for Grundfos technical support for a reply to a query I have sent them.
Does anyone have any ideas why the pressure and flow rates would drop off so significantly? I was expecting that the Home Booster would gives us a dynamic pressure just under 3.0 bar (PRV setting) and be able to maintain high flow rates across multiple outlets, but this dosen’t seem to be the case.
Many thanks
