This only happens in the winter months when ambients are low, <5C. Shower/bath filling start off fine but after a few minutes the cold sometimes overcomes the hot. Overriding the HP shower valve thermostat to increase the hot flow doesn't have any effect. This is an older house with several cold risers and hot and cold supplies weren't balanced when installing either the 10 yr old Vaillant boiler or the shower/bath supplies.
Anything I can do?
Anything I can do?
