v0.8.16

src/engine/temperature.rs

@@ -32,7 +32,7 @@ fn adjustment_allowed(zone: &Zone) -> bool {
 }
 
 fn external_room_sensor_cooling_assist(mode: &str, control_source: &str) -> f64 {
-    if mode == "cool" && matches!(control_source, "external" | "combined") { 0.5 } else { 0.0 }
+    if mode == "cool" && matches!(control_source, "external" | "combined") { 1.0 } else { 0.0 }
 }
 
 fn effective_sensor_stale_after_seconds(zone_value: u64, global_value: u64) -> u64 {

src/engine/tests.rs

@@ -588,13 +588,22 @@ mod tests {
 
     #[test]
     fn external_room_sensor_selects_lower_cooling_setpoint_only_when_used() {
-        assert_eq!(external_room_sensor_cooling_assist("cool", "external"), 0.5);
-        assert_eq!(external_room_sensor_cooling_assist("cool", "combined"), 0.5);
+        assert_eq!(external_room_sensor_cooling_assist("cool", "external"), 1.0);
+        assert_eq!(external_room_sensor_cooling_assist("cool", "combined"), 1.0);
         assert_eq!(external_room_sensor_cooling_assist("cool", "device_fallback"), 0.0);
         assert_eq!(external_room_sensor_cooling_assist("cool", "device_discrepancy_fallback"), 0.0);
         assert_eq!(external_room_sensor_cooling_assist("heat", "external"), 0.0);
     }
 
+    #[test]
+    fn external_room_sensor_cooling_keeps_full_step_below_half_degree_target() {
+        let assist = external_room_sensor_cooling_assist("cool", "external");
+        assert_eq!(round_device_setpoint("cool", true, 23.0 - assist), 22.0);
+        assert_eq!(round_device_setpoint("cool", true, 23.5 - assist), 22.0);
+        assert_eq!(round_device_setpoint("cool", true, 24.0 - assist), 23.0);
+        assert_eq!(round_device_setpoint("cool", true, 24.5 - assist), 23.0);
+    }
+
     #[test]
     fn smart_fan_uses_low_speed_when_zone_is_satisfied() {
         assert_eq!(smart_fan_speed("heat", 21.0, 21.0, None, false), 1);

src/engine/zone_control.rs

@@ -373,10 +373,10 @@ async fn control_zones(state: &AppState) -> Result<()> {
         // stop naturally when we move the target to the satisfied side of room temperature.
         let outdoor_assist = outdoor_assist_offset(effective_mode, outdoor_assist_temperature, temp, target);
         // When an independent room sensor is actually driving cooling, the indoor unit's
-        // own sensor can satisfy too early. Apply a half-degree pre-rounding bias: because
-        // GREE setpoints are sent as whole degrees, this selects the next lower whole-degree
-        // target (0.5-1.0 C below the room target). Do not stack it with outdoor assist and
-        // do not use it during device/fallback control.
+        // own sensor can satisfy too early. Apply a full-degree pre-rounding bias: because
+        // GREE setpoints are sent as whole degrees, this keeps the unit at least one full
+        // degree below the room target, including half-degree thermostat setpoints. Do not
+        // stack it with outdoor assist or use it during device/fallback control.
         let room_sensor_assist = external_room_sensor_cooling_assist(effective_mode, &zone.control_temperature_source);
         let demand_assist = outdoor_assist.max(room_sensor_assist);
         let active_target = match effective_mode {