combi condensing boiler , switch off when not in use?

[benpost]

currently i'm only using it for hot water on demand, so its not doing a thing when i'm out at work.

however the central heating temperature setting is still on 70 or so degrees. does this mean its having to keep some water heated this hot in case the heating is switched off? or does it not do anything until the heating is switched on?

just wondering whether its worth switching the boiler off when im out? i do sometimes notice it starting up when im not using any water and the heatings off.. wonder if im wasting any gas.

[John]

Which setting is on 70 - is this a setting on the boiler - or on a room thermostat?

As you mention "on demand" I presume it is a Combi - but if you can provide a make and model then the experts will be able to give a precise answer. Does it have a timer? Do you have a hot water cylinder?

[Slider]

It says COMBI in the subject line.

[benpost]

hi its a glowworm flexicom 30cx

boiler setting to control central heating temp is on 72 c, water is on

50 c but i can change these.

no room thermostat, just a basic timer to switch the boiler on for heating.

no hot water cylinder.

[Andy Dingley]

First job is to install (at least one) programmable room thermostat (Chronogyr was the last I bought, but that was a while ago). It's an easy install, and they're not too expensive, relative to fuel bills. They're a far better means of controlling domestic heating than a crude timer.

[Ed Sirett]

Probably a sub-standard installation with no room thermostat (but that's another thread).

Does the user manual give any hints any hints buzz words are:

"eco mode", hot/warm standby?

Whe you come in how long does the HW take to come through to the tap and settle down to a steady temperature. If more than 15s you can probably assume that any 'hot standby' feature is turned off.

[Paul P]

OMFG - the amount of thick people in newsgroups amazes me. You are a real TROLL! Good effort.

[Andy Hall]

.. and you are who exactly? Have we been introduced?

[John]

If the Central Heating is not switched on (due to manual selection or room thermostat) then it shouldn't matter that the boiler is set to 70.

As there is no storage (internal or external) - then I am surprised that the boiler fires when not in use. DHW is sensed with a flow sensor (not a temp sensor as in my boiler)

Sorry - - can't help but will watch with interest.

[NOSPAMnet]

And if the boiler is like mine it shows two lights when it is heating water but only one when it is on at either HW only or HW and CH but not heating water and none when it is switched off completely.

[sm_jamieson]

The "quick start" feature on several models keeps the heat exchanger etc warm despite "storing" no water, so that there is a lot less lag between hot tap on and hot water out. In such a mode, my boiler fires about once an hour for a short while. The mode can be timed to only be in operation during the day, for example. Simon.

[Mark]

Or there is a very long pipe run.

[Tony Bryer]

It seems a not unreasonable question. I have got a Glow-worm combi (24Cxi) and the recommended 'economy' setting keeps the water in the heat exchanger hot, which in turn means it fires up every 45 minutes or so whether or not you are calling for heating or hot water. Fortunately you can turn this behaviour off.

[Ed Sirett]

That's an 'economy' setting ?!? because it saves on water bills?