Gas boiler economy

Spades

I have a Immergas boiler burning LPG and the house has 2 zones with six radiators in each zone. I do use the zones separately, downstairs is used as required and upstairs is used for maybe a hour or two late in the evening to heat the bedrooms before going to bed but I have a question on this.

Do I save much gas and money by doing this? Is it really that economical, or do you actually burn twice as much gas with two zones running, and also the water can be heated separately and I often wonder, since the boiler is running heating the rads is it going to use much more gas to heat the water. Sorry if these sound like stupid questions but I didn’t get any info for the boiler when I bought the house and the manufacturer’s website hasn’t been much help.

Thanks

copper12

A gas boiler natural or lpg
zoned for heating and hot water
There are many gadgets and programmable thermostats out there .
If as you say you operate your heating for the downstairs with a room thermostat and timer; and upstairs with the same; provided you time your hot water’ to correspond with these times; then you will get the most efficiency out of you boiler
Using any boiler just for hot water’ especially for hot water during the summer’ will cost more than an electric emersion’ that’s 100 percent efficient

Reyman

An educated guess, but I'd say you're saving about 30% by leaving the upstairs rads off. This assumes the radiators upstairs are probably smaller and a certain amount of gas is being used heating the water