Optimum settings for efficient use of energy

[lucid]

A church service begins at 11.00am and finishes at noon. At what time should a heating timer be set to come on at and switch off, ensuring the minmum waste of residual heat at the end of the service and ensuring that people feel warm enough at the start of the service to achieve the most effiecient use of fuel. A brand new condensing boiler has been fitted recently.

Exact times please.

[gen2]

Too many unknowns.

For example:
Dimensions of church?
Material of walls?
Insulation?
Draughts?
Heat output of boiler?
Location and number of radiators?
Number of people expected (the human body generates heat)?
etc.

[rov1200]

I would use a bit of common logic here. You need to know how long it will take to heat up from scratch to the desired temperature. After that any further input will or should keep it at the steady state. Therefore if it takes 1 hour to reach 65% the boiler should start at 10am.

To turn the boiler off towards the end of the service you should plot the decay in temperature. If you lose 10% of the temperature every 1/4 of an hour then shutting off at 10.45am would still give a reasonable temperature at the end.

[rov1200]

Sorry shut off should be 1145am

[New Judge]

I always thought that churches were deliberately kept cold and draughty sp that the congregation did not hang around too long.

In any case, such frivolous use of energy should not be condoned in these carbon-conscious times. All the "carbon credits" that the church has should be donated to enable next year’s climate change conference (the follow up to Copenhagen) in Mexico to go ahead. It will come as great comfort to the 15,000 or so delegates flying in from around when they learn that the congregation did its bit to help enable their earth-saving jolly to go ahead with a clear conscience.

[beso]

Considering the church service is plain rubbish the heater should not be turned on at all to discourage people from coming.

[tamborine]

Keep it on 24/7 and allow the homeless to take up residence.