I had good hot water flow but explained to the salesman that I have a complicated system. The boiler is a combi but it feeds a hot water tank on the ground floor. There is also a water tank in the loft which I now believe is what feeds the system. There is a ground floor shower which is quite adequate. The salesman recommended a thermostatic bath and shower mixer. This is an aqualisa Midas 100.
When I fitted the mixer there was no flow to the shower. On cold only (i.e. blank off hot water), the shower diverter valve just stayed 'up' i.e. not a lot of pressure.
I tried to contact the bathroom shop but it is in lockdown, so I contacted aqualisa. They recommended I check the water pressure.
I bought an inexpensive water meter which indicated that the hot water pressure was low and the cold was 1.5 bar (the minimum the mixer will work at is 1 bar).
So now I am trying to find out what I should do ...
- Revert to an electric shower
- Add a pump to the hot water feed to bring the pressure up to 1.5 bar (and would this be enough to guarantee a good shower)
- Add a pump to both hot and cold feeds to bring the pressure up to, e.g., 2 bar
The technician from aqualisa didn't seem to know too much about whether this would work or not