Hot water

Al_Mac

As the weather is hot and my boiler is hot, after heating the water.

Should I be using the immersion instead? If so should I just leave it on?

a&akay

Your electricity will be at least 3x your gas per kWhr unless you are on economy 7 for electricty. You will be losing some heat in your pipework from your boiler to your hot water tank and in the boiler itself but this will be negligible in comparison.

a&akay

Yes even if you leave it on constant during the day. The boiler will cycle on and off as the water heats and cools. Once the thermostat falls below its set point, this will happen. The total energy you use in gas usage costs will not be more than using electricity for hot water even for this wasted energy. If you want to save more, then set your timer to heat the hot water for the periods you use it depending on your lifestyle. Eg, if you/your family are at work/school during the week then set it to heat only in the morning for that usage and again in the evening for your usage then. Your controls may even allow for different set points for weekends/weekdays.

Ken68

Depends how many in the family.
No point in heating a whole tankful of water if only a little is used, might as well put the kettle on, and use an electric shower.
Even better with E7 hours when you need hot water anyway, as in personal washing and dishwashing.

billy_bulldog

A few years ago we had an immersion heater fitted. Now, from about May to October (when we don't really need the central heating) we switch off the boiler completely and program the immersion to come on for 2 hours just before dawn (still economy 7 hours). We than flick it on in the evening for an hour if needed, just before anyone uses the bath - but mostly we shower at this time of year as it's more refreshing.

Our gas usage for the summer months is 0 units, and the electric is not much more than normal as well. It certainly works for us, plus not running your boiler for 6 out of 12 months helps to extend its working life, and a new immersion heater fitted is only about £50 if it ever fails.