Expansion vessel is not needed with these small water heaters - the tundish is built into the valve and allows water to escape when it is heated and expands! When the water reaches the set temperature the dripping stops. This from 12...
The combination valve is made by Caleffi and is an isolating, check valve and pressure relief valve, newer version below,
There should be an expansion vessel somewhere...
I have to agree with exedon 2 the only real way of softening the water is with a salt water softener the block salt models are quite expensive but are the best, the other items you listed will not stop the formation of scale they may...
Ideal Standard close coupled toilets installed in new build house ten years ago.
Having received a hefty water bill for last half year (May to December 2024) water usage from Southern Water I was a bit concerned! It was double compared...