15 minutes on, 15 minutes off technique, combi boiler - halving winter fuel bill?!

pault123

Instead of my usual on from 6pm - midnight solid, i'm going to try using my timer to cycle the heating on and off every 15 minutes.
180 hours a month in winter normally







So instead of 6 hours a night, it will be on for 3 hours a night approx.

Over a month normally 180 hours should become 90 hours usage.

Radiator setting is just above minimum as per the pic, I leave it like this all winter and don't turn it higher to initially heat up the house, nor do I have a thermostat to set the temp throughout the house.

So far tonight the difference has been pretty minimal considering i've had it on for half the usual time :beer: House is very toasty

Anyone else tried this or any thoughts?

southcoastrgi

the pressure in the heating is too high for that temp setting & it looks like your timer has overheated or you have another prob by the looks of those black marks

penrhyn

Indeed looks like there is a problem with the pressure.
The boiler is set too low as well.

HappyMJ

You'll save a little (it won't be half though) and if you aren't feeling the house cool down during the 15 minute off period which you shouldn't then stick with it. It should at the very least stop the house getting too hot. I'd consider getting a thermostat installed.

pault123

southcoastrgi wrote: »

the pressure in the heating is too high for that temp setting & it looks like your timer has overheated or you have another prob by the looks of those black marks

Its always gone to 2 when turned on and drops to 0.5/1 when off? Have it serviced by Worcester Bosch each year and it always passes.

The marks around the timer are just dirt, the boiler is 5 years old :rotfl:

pault123

penrhyn wrote: »

Indeed looks like there is a problem with the pressure.
The boiler is set too low as well.

If I turn the radiator temp higher, the house gets too hot though? along with gas consumption being far higher? (i dont have a thermostat keep in mind)

Hot water isnt controlled by this dial, and is always red hot.

pault123

HappyMJ wrote: »

You'll save a little (it won't be half though) and if you aren't feeling the house cool down during the 15 minute off period which you shouldn't then stick with it. It should at the very least stop the house getting too hot. I'd consider getting a thermostat installed.

Last night felt fine, but i'm going to try 30 mins off and 30 mins on tonight to compare.

HappyMJ

pault123 wrote: »

Last night felt fine, but i'm going to try 30 mins off and 30 mins on tonight to compare.

I'd try 30 minutes off. 15 minutes on...

penrhyn

pault123 wrote: »

If I turn the radiator temp higher, the house gets too hot though? along with gas consumption being far higher? (i dont have a thermostat keep in mind)

Hot water isnt controlled by this dial, and is always red hot.

Don't you have TRVs on the radiators either?

spinningsheep

The thermostat on the boiler is set far too low, at that setting the flow temp of the boiler is about 30 degrees, ideal for underfloor heating that is on all the time, but unless you have huge oversized radiators, I cannot see how you are getting any level of useable heat into the room from what must be tepid radiators. The temperature of the hot water is preset at about 50 degrees on the 24i, cannot be controlled. Why not try 2 hours set to about 3 o clock on the thermostat, in 3 bursts as the day goes along?

pault123

penrhyn wrote: »

Don't you have TRVs on the radiators either?

no just flow control valves, have them all set a bit lower downstairs so more flow goes upstairs and the hear distributes quite well