Sensor Timing algorithm
HVAC Alibi
Waits for a real HVAC action transition so a safe correction lands near a normal thermostat event.
These algorithms make corrections land near real house signals instead of on a robotic beat, while still stepping aside when room comfort needs direct cooling.
The short version
Waits for a real HVAC action transition so a safe correction lands near a normal thermostat event.
What it watches
The current Home Assistant hvac_action, the last action transition, recent wall touches, and room temperature.
How it decides
After repeated wall touches, while the room is still inside the safety band, it can hold a safe correction until hvac_action changes (for example idle to cooling or cooling to idle). A recent transition can also clear the hold. Direct comfort needs, upstairs heat, or a too-warm room bypass the wait immediately.
What it changes
Delays only safe corrections until a real HVAC action transition or the max hold expires.
Safety boundaries
- Uses the real inputs listed above. It does not invent thermostat, weather, usage, or sensor state.
- Changes only the output listed above. Thermostat-affecting work goes through Home Assistant or returns a real error.
- The global AC Defender rules still apply: the website target remains the floor for cooling commands, the worker keeps refreshing real Home Assistant state 24/7, and comfort/safety rules are not bypassed by decorative timing.
Settings
HvacActionAlibiEnabledHvacActionAlibiTriggerTouchesHvacActionAlibiTransitionWindowSecondsHvacActionAlibiMaxHoldMinutesHvacActionAlibiSafetyBandCelsius
Where to see it
- Defense page: live card with state, verdict, evidence, and metrics.
- Guide page: generated from the same guard catalog entry.
- Source:
Guards/GuardCatalog.csdescribes this page; the implementation is coordinated byServices/DefenderStateStore.csandServices/AcDefenderService.cs.
Failure modes
If HVAC Alibi cannot obtain one of its required real inputs, it reports a blocked, held, or unavailable result and leaves the background worker’s Home Assistant refresh running. It never fills a missing room reading, audit event, weather sample, usage value, or device state with a simulator value. If a real Home Assistant command is rejected, the user sees the service’s actual error and the article’s surface remains available for recovery.
Security considerations
This feature consumes only the configured Home Assistant entity data, local settings, and the audit context named above. Tokens and credentials stay in the server environment; the static documentation site does not collect analytics, transmit search text, or embed third-party assets. Logs and exports should be reviewed before sharing because real entity names and timestamps can identify a household.
Verification
Verify the shipped behavior at the feature’s live page or endpoint, then run the repository’s documented build and test commands. Confirm the real-input and real-error paths, keyboard access, reduced-motion behavior, and a 390 px viewport without horizontal overflow. Record the exact commit and workflow result when publishing a release; a static screenshot alone is not proof of a live Home Assistant command.
Suggested articles
- Feature briefs — find every documented surface and guard.
- Defender Logic — follow the complete decision cycle and its bypass rules.
- Settings — inspect persisted configuration, language modes, and safety limits.