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- Thermostat setbacks
How far back to turn it, and when not to
Setting the thermostat back while a building is empty saves energy. How far back depends on what is producing the heat or the cooling — and on a heat pump the usual advice is wrong.
The planner
General guidance, not a guarantee of savings — a building's insulation, glass and equipment all change the result. Nothing is sent anywhere; it runs in your browser.
Worth knowing
Four things the planner cannot see
- Adaptive recoveryMany thermostats learn how long the building takes to come back and start early so it is at temperature at the time you set. If yours has it, use it — it removes the guesswork.
- "Emergency heat" is not a setback toolOn a heat pump that setting runs the backup heat only. It is for a failed compressor, not for a cold morning.
- Buildings with people in themAn office with a fixed occupancy schedule is easier than a shop with variable hours. Schedules that do not match reality get overridden and then ignored.
- Pipes and stored goodsDo not set back so far that pipes, stock or equipment are at risk in a cold snap. A deep weekend setback in an unoccupied building is where that goes wrong.
