Economy 7 vs Oil for heating water

donteatthat

We have an oil filled boiler (2 years old, Firebird) and are moving onto an economy7 tarriff. I am wondering if it would be beneficial to move the hot water onto the immersion heater and put it on a timer rather than use the oil via the boiler to heat it up. Does anyone know if this will be cheaper as my OH thinks the immersion heater is more for emergencies rather than day-to-day use whereas I can't see the concern as I expect that heating the water from 5-6am on the Economy7 tarriff would be cheaper than using the oil to do it.
Thanks.

HappyMJ

As long as your E7 rate is competitive at around 5p then it's cheaper to use the immersion heater. You might need to set it for 2 hours from 4am to 6am. If all the hot water has been used it can take up to 2 hours to fully reheat a cylinder from cold.

Terrylw1

Just check your Night rate time settings. If your meter is a time switch metet, the supplier can easily see this data but if its radio teleswitch (nightly updated signal) the suppliers are often unaware of how they are working so be careful so as to maximise any Night rate charges.