Combi boiler temperatures

[Clicheinaqashqai]

What temperature do you have your combi boiler set to for heating and hot water?

I thought to set the hot water to 45⁰ so that we aren't adding much cold for baths and showers and can always boiler the kettle if we need hotter for washing up etc. However online it says 50-60 is best for efficiency but I am struggling to understand why?

We have been on a fix until now and I am on SMP so I am slightly terrified of our increase in bills

Thanks

You shouldn't set it below a certain temp (think it's 65?) because of the risk of legionella

I thought that was for of you had a hot water tank and not a combi boiler?

The boiler temp is always hotter than the water from the hot tap, it can drop 10-15% from boiler to tap. 55-60 degree boiler temp for hot water should be sufficient.

For radiator flow temperature, 60-65 should enable the return temp to enable efficient condensing, it also prolongs the life of the boiler.