DIY Doctor UK DIY Forums

I have an oil fuelled combi boiler central heating system with a basic timer and honeywell mechanical thermostat. At the moment the timer has two on and off settings each day and can be used on timed mode, off or overide. If I leave the timer in the timed position then we have hot water twice per day with optional heating depending on the thermostat level. If I leave the timer in the overide position then whilst I can control the heating with the thermostat the hot water seems to be kept at a constant temperature all day / night without even turning on the tap which is drinking up the oil from our storage tank. There is a summer / winter switch on the boiler but this is just for the heating and appears to be operating correctly. Basically the problem seems to be that I can't leave the boiler on at all times with just the thermostat operating the heating because the boiler will be keeping the water hot ! Is this just the way this oil fuelled boiler (Camray Combi) operates or could I replace the thermostat / timer with a programmable one that would allow more control ? Many thanks

I'm no oil expert; nor have I ever had the pleasure of a Camray - I would check your water flow switch to make sure it hasn't got stuck in the "on" position.