Glossary · Heating, cooling & ventilation
Thermostat setback
Also called: night setback · temperature setback · setback schedule · setback thermostat
Lowering the heat (or raising the cooling setpoint) while you sleep or are away, then returning to normal before you need it.
What it means
A house loses heat more slowly when it's cooler inside, so a setback saves energy even after counting the recovery. With a heat pump, deep or sudden setbacks can make the system call for auxiliary heat during recovery, wiping out savings unless the thermostat is heat-pump-aware. Some slow-responding hot-water (hydronic) systems also gain little.
Why it matters in an audit
It's free savings once set up, and audits often suggest a schedule alongside upgrades.
Typical numbers
Reference values with their sources. Your energy advisor’s report gives the figure for your own house.
| What | Value | Source |
|---|---|---|
| NRCan | About 2% of heating energy for each 1°C (2°F) of setback over 8 hours; don't go below 17°C (63°F), to limit moisture in exterior walls | natural-resources.canada.ca ↗ |