Air-source heat pump outdoor unit beside a house in the snow

Generic photo: PeterEastern · CC BY-SA 4.0

Field pattern: big electric bill after a setback schedule (recovery brings on aux strips)

When the gap between room temperature and setpoint is large, most thermostats bring on aux strips to recover. Strips cost several times more to run than the heat pump, so a deep setback can wipe out its savings. Fix it with smaller setbacks, heat-pump-aware recovery, and an outdoor-temperature aux lockout.

Cross-checked ~30 min easyBrands: All

Before you start

Configuration only; no electrical work needed

Diagnostic steps

Unlock all 6 steps with expected values

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