tiling behind a towel radiator

[Fekin]

Be carefull with combi systems they can be a nightmare to get pressure right and you could be wasting a lot of your time farting about getting it right.

Really ?

I've never found a complicated one yet postie.

They simply have the pressure gauge, which will have dropped a little after a rad change, then a simple valve to top up with, and the gauge only takes a second or so to register the change in pressure as you add a bit in.