Hi,
I have fitted an Altecnic mini expansion vessel/arrestor on my mains cold supply feed to the combi boiler (we have a water meter fitted).
Prior to fitting:
Static Pressure (no flow conditions): ~5 bar
Flow Pressure (one cold tap open): ~4 bar
Temporary spike when shutting tap quickly: ~7 bar
This clip from the company on youtube suggests setting the vessel pressure to be slightly higher than the system pressure (at 1 min 23 seconds into the below video). So, I've set it to just above 5 bar taking static pressure under no flow conditions to be "system pressure".
How to Remove Water Hammer? - YouTube
I've then re-tested with my gauge and am no longer getting temporary spikes when suddenly shutting off the tap, it just goes straight back to approx 5 bar very quickly.
However, the pipe banging (which was present before) has got louder (it is in the same location, so assume the pipes may not be securely fixed). This occurs when you next open a tap (as opposed to when closing a tap). I'm guessing it has something to do with the built up pressure suddenly being released, BUT I thought the mini expansion vessel was there to reduce pipe banging.
I did consider lowering the expansion vessel pressure, but have followed the manufacturers guidance, thinking that if I lowered it to less than the static (no flow) water pressure, the water pressure would overcome the air pressure and fill the vessel negating its effectiveness.
Any ideas greatly welcome as I'm worried I've not set the pressure correctly!
I have fitted an Altecnic mini expansion vessel/arrestor on my mains cold supply feed to the combi boiler (we have a water meter fitted).
Prior to fitting:
Static Pressure (no flow conditions): ~5 bar
Flow Pressure (one cold tap open): ~4 bar
Temporary spike when shutting tap quickly: ~7 bar
This clip from the company on youtube suggests setting the vessel pressure to be slightly higher than the system pressure (at 1 min 23 seconds into the below video). So, I've set it to just above 5 bar taking static pressure under no flow conditions to be "system pressure".
How to Remove Water Hammer? - YouTube
I've then re-tested with my gauge and am no longer getting temporary spikes when suddenly shutting off the tap, it just goes straight back to approx 5 bar very quickly.
However, the pipe banging (which was present before) has got louder (it is in the same location, so assume the pipes may not be securely fixed). This occurs when you next open a tap (as opposed to when closing a tap). I'm guessing it has something to do with the built up pressure suddenly being released, BUT I thought the mini expansion vessel was there to reduce pipe banging.
I did consider lowering the expansion vessel pressure, but have followed the manufacturers guidance, thinking that if I lowered it to less than the static (no flow) water pressure, the water pressure would overcome the air pressure and fill the vessel negating its effectiveness.
Any ideas greatly welcome as I'm worried I've not set the pressure correctly!