Boiler

[AngelEyes46]

Hi, hot water only work when I turn the immersion on. Central heating is fine, but if anyone wants a shower or bath, immersion needs to be switched on

Would welcome any ideas or suggestions

What colour is your hot water cylinder?

How old do you think the boiler is? Does it have a pressure gauge? When was it last serviced?

Is the highest radiator in the house hot all over?

Please photograph your timer/programmer

When did the HW last work correctly?

Have a look round your boiler and your cylinder for a motorised valve (or two) looking something like one of these.

www.screwfix.com/search?search=Port+valve&brand=drayton|honeywell_home&category=cat830950

Makes my day when PigletJohn responds.