FA-92668 / HVAC thermostat control / Member archive

Auxiliary heat releases as soon as DM rises above its start point · case 03

The immersion heater chatters on and off around aux_dm.

Member previewVariant 3 · 3 implementations · 8 checks per implementation

Case contract

Hydronic heat pump degree-minute controller, one sample per minute of [supply_temp, target_supply] in whole F. Degree-minutes DM accumulate supply - target each minute and are clamped to [floor, 100]. The compressor starts when DM <= start_dm and stops when DM >= stop_dm. Auxiliary heat starts when DM <= aux_dm and stops when DM >= start_dm. Decisions use the DM value after this minute's update. Return [DM, compressor, aux] per minute.

Why this case matters

Residential and light-commercial thermostats make these decisions sample by sample; each defect changes equipment calls in a way that shows up as short cycling, comfort complaints or equipment stress.

One recorded failure

Sample boundary fixture

This sample comes from the broken implementation of a controlled reproducer.

Boundary fixture	Actual	Expected	Outcome
regression: scenario 7	`[[-29, false, false], [-53, false, false], [-79, true, false], [-103, true, false], [-126, true, false], [-155, true, true], [-185, true, true], [-205, true, true], [-226, true, true], [-196, true, true], [-167, true, true], [-138, true, false], [-112, true, false], [-83, true, false], [-76, true, false], [-64, true, false], [-50, true, false], [-42, true, false], [-33, true, false], [-26, true, false]]`	`[[-29, false, false], [-53, false, false], [-79, true, false], [-103, true, false], [-126, true, false], [-155, true, true], [-185, true, true], [-205, true, true], [-226, true, true], [-196, true, true], [-167, true, true], [-138, true, true], [-112, true, true], [-83, true, true], [-76, true, true], [-64, true, true], [-50, true, false], [-42, true, false], [-33, true, false], [-26, true, false]]`	Failed

MEMBER ARCHIVE

The complete case is available to members.

This record includes three runnable implementations, regression fixtures, execution results, and source hashes.

Member access is invitation-based. Sign in with your invited account to inspect the sources.