Cost of the boiler running without heating on?

lozzaman

macman wrote: »

So it's pointless turning it off at the main switch, or even turning the DHW/CH temp controls down. The DHW side can't fire the boiler while you are out (unless your cat decides to run itself a bath), and if the room 'stat is down below the ambient temp then neither can the CH side fire it.
A modern combi doesn't have a pilot light either, so it's costing precisely zero in gas while it's idle. I'm still puzzled as to why you think it's money-saving to turn it off?
The only overhead is a fractional amount of electricity to power the ignition circuit etc.

Some boilers will activate the pump twice a day for 1 minute as well to stop the pump seizing.

I'd leave it on, with the thermostat down. Get a programmer fitted too when you can.

Pincher

Harm? Potentially.

The Sky+HD power supply is prone to failure if you disconnect the AC supply frequently. Unfortunately, if it hangs, you have no choice but to unplug it.

When you disconnect/reconnect the AC supply, there is a transient spike, akin to a micro lightning strike. In all electrical devices, this is managed by surge suppression circuitry.

Basically, if a device is supposed to be switched on/off for hundreds of thousands of times, they use heavier duty capacitors etc. For devices like a boiler and Sky+HD, that are on standby or active duty and hardly ever switched off, they tend to use inferior components that can survive fewer spikes.

So every time you use that switch, you are attacking a poor little surge suppression capacitor with a little zap. A decent one will take it like a man for thousands of times, a wimpy one will survive maybe a few hundred times.

So it's up to you, do you feel lucky?

Cardew will probably say something about quick blow surge fuses,
but you are not going to open the boiler to change that yourself,
so it's a call out whether it's a capacitor or a fuse.

Hank_Marvin

Well i've had a good read off the replies to my boiler query. So i've changed my set up, I am leaving boiler on now and just wondering if i've got it set up properly. I've got the thermostat set at min which on the dial is 10 for when i'm out all day, and when i return i knock it up to 16. I've also got the eco button on the boiler on.

The 2 knobs on boiler are for heating & water, heating is set to max and water is set to 2 but when i need hot water i'll turn it up. I've got the water set at 2 because it'll stop the boiler from reheating the water which is a waste. Now on the boiler is a digital readout can some one tell me what these numbers mean, as i'm not to sure but think it could be to do with the water temp??

lozzaman

The eco button is probably to stop pre-heating of hot water? If you set the temperature dial where you like on ECO it won't make any difference.

What do the digital readouts show?
As for the heating, you might want to turn the dial down a bit, depending on how high your return temperatures are. You want to make sure these are no higher than around 55c so that the boiler condenses.

Otherwise everything sounds OK.

macman

Is it not possible to disable the hot water store function on these combi's?

aelitaman

macman wrote: »

Is it not possible to disable the hot water store function on these combi's?

If you have a programmer that can set timing for both hot water and central heating then the answer is yes. But most people that have a combi believe the marketing of hot water on demand and did not understand that the boiler has a store and so only had a programmer fitted that timed the central heating.

I was one, I wished I had a dual programmer fitted but what I do now is switch the store off manually by turning the hot water temp dial on the boiler to zero when not required. Also hot water delivery is not dependent on the store being up to temp. The store is just used to provide a high flow so if you want a shower you can turn the hot water on at the boiler and jump in the shower straight away.