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FA-92776 / HVAC thermostat control / Open access

Reversing valve terminal type is inverted · case 01

An O-type heat pump blows cold air on a heating call.

Verified by executionVariant 1 · 8 checks per implementationDownload source bundle ↓JSON ↗

ROOT CAUSE

O-type is energized for heat and B-type for cool.

VERIFIED REPAIR

Energize O for cooling and B for heating.

Unsuccessful approach: Energizing on cooling regardless of valve type breaks B-type equipment.

Case contract

Heat pump reversing valve output (O/B terminal) and compressor per sample; samples are the call (heat, cool or None). An O-type valve is energized for cooling, a B-type for heating. The valve is de-energized at power-up and holds its last position while idle. On a sample where the valve changes position the compressor waits (off) for pressure equalization. Return [compressor, valve_energized].

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.

1 / The failure

Exit 1
"""Failure Map reference implementation. Python standard library only."""
import json

N = 1
observations = []
def solve(valve_type, samples):
    valve = False
    out = []
    for call in samples:
        if call is None:
            out.append([False, valve])
            continue
        want = (call == 'heat') if valve_type == 'O' else (call == 'cool')
        changed = want != valve
        valve = want
        out.append([not changed, valve])
    return out
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
fixtures = [[['regression: O valve season change',
   ['O', ['cool', 'cool', None, 'heat', 'heat', 'cool']],
   [[False, True], [True, True], [False, True], [False, False], [True, False], [False, True]]],
  ['regression: B valve idle hold',
   ['B', ['heat', None, 'heat']],
   [[False, True], [False, True], [True, True]]],
  ['regression: first call heat on O',
   ['O', ['heat', 'heat', None, 'cool']],
   [[True, False], [True, False], [False, False], [False, True]]],
  ['regression: first call cool on B',
   ['B', ['cool', None, 'cool', 'heat']],
   [[True, False], [False, False], [True, False], [False, True]]],
  ['regression: scenario 1',
   ['B', ['cool', 'heat', 'heat', None, None, 'cool', 'cool', 'heat', 'heat', 'heat', 'heat']],
   [[True, False],
    [False, True],
    [True, True],
    [False, True],
    [False, True],
    [False, False],
    [True, False],
    [False, True],
    [True, True],
    [True, True],
    [True, True]]],
  ['regression: scenario 2',
   ['B',
    ['heat',
     'heat',
     'cool',
     'cool',
     'heat',
     None,
     'heat',
     'cool',
     'heat',
     'heat',
     'cool',
     None,
     'heat',
     'cool']],
   [[False, True],
    [True, True],
    [False, False],
    [True, False],
    [False, True],
    [False, True],
    [True, True],
    [False, False],
    [False, True],
    [True, True],
    [False, False],
    [False, False],
    [False, True],
    [False, False]]],
  ['regression: scenario 3',
   ['O', ['cool', 'cool', 'cool', 'heat', None, None, 'heat', 'cool', 'heat', 'heat', None, 'heat', 'heat']],
   [[False, True],
    [True, True],
    [True, True],
    [False, False],
    [False, False],
    [False, False],
    [True, False],
    [False, True],
    [False, False],
    [True, False],
    [False, False],
    [True, False],
    [True, False]]],
  ['regression: scenario 4',
   ['B', [None, 'heat', 'cool', 'cool', 'cool', 'cool', 'heat', 'heat', None, 'cool']],
   [[False, False],
    [False, True],
    [False, False],
    [True, False],
    [True, False],
    [True, False],
    [False, True],
    [True, True],
    [False, True],
    [False, False]]]],
 [['regression: B valve idle hold',
   ['B', ['heat', None, 'heat']],
   [[False, True], [False, True], [True, True]]],
  ['regression: scenario 1',
   ['B', [None, None, 'heat', None, 'cool', 'cool', 'cool', 'heat', None, 'cool', None]],
   [[False, False],
    [False, False],
    [False, True],
    [False, True],
    [False, False],
    [True, False],
    [True, False],
    [False, True],
    [False, True],
    [False, False],
    [False, False]]],
  ['regression: O valve season change',
   ['O', ['cool', 'cool', None, 'heat', 'heat', 'cool']],
   [[False, True], [True, True], [False, True], [False, False], [True, False], [False, True]]],
  ['regression: first call heat on O',
   ['O', ['heat', 'heat', None, 'cool']],
   [[True, False], [True, False], [False, False], [False, True]]],
  ['regression: first call cool on B',
   ['B', ['cool', None, 'cool', 'heat']],
   [[True, False], [False, False], [True, False], [False, True]]],
  ['regression: scenario 2',
   ['B', ['heat', 'cool', 'heat', None, 'cool', 'heat', None, 'heat', None, 'cool', None]],
   [[False, True],
    [False, False],
    [False, True],
    [False, True],
    [False, False],
    [False, True],
    [False, True],
    [True, True],
    [False, True],
    [False, False],
    [False, False]]],
  ['regression: scenario 3',
   ['B', [None, 'heat', None, None, None, None, 'cool', 'heat', 'heat', None]],
   [[False, False],
    [False, True],
    [False, True],
    [False, True],
    [False, True],
    [False, True],
    [False, False],
    [False, True],
    [True, True],
    [False, True]]],
  ['regression: scenario 4',
   ['B', ['heat', 'cool', 'cool', 'heat', 'heat', None, 'heat']],
   [[False, True], [False, False], [True, False], [False, True], [True, True], [False, True], [True, True]]]],
 [['regression: first call heat on O',
   ['O', ['heat', 'heat', None, 'cool']],
   [[True, False], [True, False], [False, False], [False, True]]],
  ['regression: scenario 1',
   ['B', ['cool', 'heat', 'heat', 'cool', 'cool', None, 'cool', 'heat', 'heat', None, None, 'heat']],
   [[True, False],
    [False, True],
    [True, True],
    [False, False],
    [True, False],
    [False, False],
    [True, False],
    [False, True],
    [True, True],
    [False, True],
    [False, True],
    [True, True]]],
  ['regression: O valve season change',
   ['O', ['cool', 'cool', None, 'heat', 'heat', 'cool']],
   [[False, True], [True, True], [False, True], [False, False], [True, False], [False, True]]],
  ['regression: B valve idle hold',
   ['B', ['heat', None, 'heat']],
   [[False, True], [False, True], [True, True]]],
  ['regression: first call cool on B',
   ['B', ['cool', None, 'cool', 'heat']],
   [[True, False], [False, False], [True, False], [False, True]]],
  ['regression: scenario 2',
   ['O', [None, 'cool', 'heat', 'cool', 'heat', 'heat']],
   [[False, False], [False, True], [False, False], [False, True], [False, False], [True, False]]],
  ['regression: scenario 3',
   ['B', ['cool', 'heat', None, None, None, 'heat', 'heat', 'cool']],
   [[True, False],
    [False, True],
    [False, True],
    [False, True],
    [False, True],
    [True, True],
    [True, True],
    [False, False]]],
  ['regression: scenario 4',
   ['O', ['heat', 'heat', 'heat', 'heat', 'heat', 'cool', None, 'cool', 'cool', None]],
   [[True, False],
    [True, False],
    [True, False],
    [True, False],
    [True, False],
    [False, True],
    [False, True],
    [True, True],
    [True, True],
    [False, True]]]],
 [['regression: first call cool on B',
   ['B', ['cool', None, 'cool', 'heat']],
   [[True, False], [False, False], [True, False], [False, True]]],
  ['regression: scenario 7',
   ['B', ['heat', 'heat', None, None, 'cool', None, 'cool', None, 'cool', None, None, None, 'heat', 'cool']],
   [[False, True],
    [True, True],
    [False, True],
    [False, True],
    [False, False],
    [False, False],
    [True, False],
    [False, False],
    [True, False],
    [False, False],
    [False, False],
    [False, False],
    [False, True],
    [False, False]]],
  ['regression: O valve season change',
   ['O', ['cool', 'cool', None, 'heat', 'heat', 'cool']],
   [[False, True], [True, True], [False, True], [False, False], [True, False], [False, True]]],
  ['regression: B valve idle hold',
   ['B', ['heat', None, 'heat']],
   [[False, True], [False, True], [True, True]]],
  ['regression: first call heat on O',
   ['O', ['heat', 'heat', None, 'cool']],
   [[True, False], [True, False], [False, False], [False, True]]],
  ['regression: scenario 1',
   ['O', ['heat', 'cool', None, 'cool', None, None, 'cool']],
   [[True, False], [False, True], [False, True], [True, True], [False, True], [False, True], [True, True]]],
  ['regression: scenario 2',
   ['B', ['cool', 'cool', 'heat', None, 'cool', 'cool', None, 'cool']],
   [[True, False],
    [True, False],
    [False, True],
    [False, True],
    [False, False],
    [True, False],
    [False, False],
    [True, False]]],
  ['regression: scenario 3',
   ['O', ['cool', 'cool', None, 'heat', 'heat', 'heat', 'cool', 'heat', None, 'heat', None, 'heat']],
   [[False, True],
    [True, True],
    [False, True],
    [False, False],
    [True, False],
    [True, False],
    [False, True],
    [False, False],
    [False, False],
    [True, False],
    [False, False],
    [True, False]]]],
 [['regression: scenario 1',
   ['O', ['heat', None, 'cool', None, 'heat', 'cool', 'heat', 'cool', None, None, None]],
   [[True, False],
    [False, False],
    [False, True],
    [False, True],
    [False, False],
    [False, True],
    [False, False],
    [False, True],
    [False, True],
    [False, True],
    [False, True]]],
  ['regression: scenario 7',
   ['B', ['heat', 'heat', 'cool', None, 'cool', 'heat', 'cool', 'heat', 'heat', 'cool', None]],
   [[False, True],
    [True, True],
    [False, False],
    [False, False],
    [True, False],
    [False, True],
    [False, False],
    [False, True],
    [True, True],
    [False, False],
    [False, False]]],
  ['regression: O valve season change',
   ['O', ['cool', 'cool', None, 'heat', 'heat', 'cool']],
   [[False, True], [True, True], [False, True], [False, False], [True, False], [False, True]]],
  ['regression: B valve idle hold',
   ['B', ['heat', None, 'heat']],
   [[False, True], [False, True], [True, True]]],
  ['regression: first call heat on O',
   ['O', ['heat', 'heat', None, 'cool']],
   [[True, False], [True, False], [False, False], [False, True]]],
  ['regression: first call cool on B',
   ['B', ['cool', None, 'cool', 'heat']],
   [[True, False], [False, False], [True, False], [False, True]]],
  ['regression: scenario 2',
   ['B', [None, None, None, None, 'cool', None, 'heat', 'cool', None]],
   [[False, False],
    [False, False],
    [False, False],
    [False, False],
    [True, False],
    [False, False],
    [False, True],
    [False, False],
    [False, False]]],
  ['regression: scenario 3',
   ['O', ['heat', 'cool', 'cool', 'heat', 'heat', None, 'heat', None, 'heat', 'heat', 'cool', 'cool']],
   [[True, False],
    [False, True],
    [True, True],
    [False, False],
    [True, False],
    [False, False],
    [True, False],
    [False, False],
    [True, False],
    [True, False],
    [False, True],
    [True, True]]]]]
for label, args, expected in fixtures[N-1]:
    check(label, solve(*args), expected)
print(json.dumps({"observations": observations, "passed": all(x["passed"] for x in observations)}, ensure_ascii=False))
raise SystemExit(0 if all(x["passed"] for x in observations) else 1)
Boundary fixtureActualExpectedOutcome
regression: O valve season change[[True, False], [True, False], [False, False], [False, True], [True, True], [False, False]][[False, True], [True, True], [False, True], [False, False], [True, False], [False, True]]Failed
regression: B valve idle hold[[True, False], [False, False], [True, False]][[False, True], [False, True], [True, True]]Failed
regression: first call heat on O[[False, True], [True, True], [False, True], [False, False]][[True, False], [True, False], [False, False], [False, True]]Failed
regression: first call cool on B[[False, True], [False, True], [True, True], [False, False]][[True, False], [False, False], [True, False], [False, True]]Failed
regression: scenario 1[[False, True], [False, False], [True, False], [False, False], [False, False], [False, True], [True, True], [False, False], [True, False], [True, False], [True, False]][[True, False], [False, True], [True, True], [False, True], [False, True], [False, False], [True, False], [False, True], [True, True], [True, True], [True, True]]Failed
regression: scenario 2[[True, False], [True, False], [False, True], [True, True], [False, False], [False, False], [True, False], [False, True], [False, False], [True, False], [False, True], [False, True], [False, False], [False, True]][[False, True], [True, True], [False, False], [True, False], [False, True], [False, True], [True, True], [False, False], [False, True], [True, True], [False, False], [False, False], [False, True], [False, False]]Failed
regression: scenario 3[[True, False], [True, False], [True, False], [False, True], [False, True], [False, True], [True, True], [False, False], [False, True], [True, True], [False, True], [True, True], [True, True]][[False, True], [True, True], [True, True], [False, False], [False, False], [False, False], [True, False], [False, True], [False, False], [True, False], [False, False], [True, False], [True, False]]Failed
regression: scenario 4[[False, False], [True, False], [False, True], [True, True], [True, True], [True, True], [False, False], [True, False], [False, False], [False, True]][[False, False], [False, True], [False, False], [True, False], [True, False], [True, False], [False, True], [True, True], [False, True], [False, False]]Failed

SHA-256 / 07a66995eac39151ddc2b533c677a2cc1f3caa9f551e4fb8d0fcd9ca9459e41d

2 / The unsuccessful fix

Exit 1
"""Failure Map reference implementation. Python standard library only."""
import json

N = 1
observations = []
def solve(valve_type, samples):
    valve = False
    out = []
    for call in samples:
        if call is None:
            out.append([False, valve])
            continue
        want = call == 'cool'
        changed = want != valve
        valve = want
        out.append([not changed, valve])
    return out
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
fixtures = [[['regression: O valve season change',
   ['O', ['cool', 'cool', None, 'heat', 'heat', 'cool']],
   [[False, True], [True, True], [False, True], [False, False], [True, False], [False, True]]],
  ['regression: B valve idle hold',
   ['B', ['heat', None, 'heat']],
   [[False, True], [False, True], [True, True]]],
  ['regression: first call heat on O',
   ['O', ['heat', 'heat', None, 'cool']],
   [[True, False], [True, False], [False, False], [False, True]]],
  ['regression: first call cool on B',
   ['B', ['cool', None, 'cool', 'heat']],
   [[True, False], [False, False], [True, False], [False, True]]],
  ['regression: scenario 1',
   ['B', ['cool', 'heat', 'heat', None, None, 'cool', 'cool', 'heat', 'heat', 'heat', 'heat']],
   [[True, False],
    [False, True],
    [True, True],
    [False, True],
    [False, True],
    [False, False],
    [True, False],
    [False, True],
    [True, True],
    [True, True],
    [True, True]]],
  ['regression: scenario 2',
   ['B',
    ['heat',
     'heat',
     'cool',
     'cool',
     'heat',
     None,
     'heat',
     'cool',
     'heat',
     'heat',
     'cool',
     None,
     'heat',
     'cool']],
   [[False, True],
    [True, True],
    [False, False],
    [True, False],
    [False, True],
    [False, True],
    [True, True],
    [False, False],
    [False, True],
    [True, True],
    [False, False],
    [False, False],
    [False, True],
    [False, False]]],
  ['regression: scenario 3',
   ['O', ['cool', 'cool', 'cool', 'heat', None, None, 'heat', 'cool', 'heat', 'heat', None, 'heat', 'heat']],
   [[False, True],
    [True, True],
    [True, True],
    [False, False],
    [False, False],
    [False, False],
    [True, False],
    [False, True],
    [False, False],
    [True, False],
    [False, False],
    [True, False],
    [True, False]]],
  ['regression: scenario 4',
   ['B', [None, 'heat', 'cool', 'cool', 'cool', 'cool', 'heat', 'heat', None, 'cool']],
   [[False, False],
    [False, True],
    [False, False],
    [True, False],
    [True, False],
    [True, False],
    [False, True],
    [True, True],
    [False, True],
    [False, False]]]],
 [['regression: B valve idle hold',
   ['B', ['heat', None, 'heat']],
   [[False, True], [False, True], [True, True]]],
  ['regression: scenario 1',
   ['B', [None, None, 'heat', None, 'cool', 'cool', 'cool', 'heat', None, 'cool', None]],
   [[False, False],
    [False, False],
    [False, True],
    [False, True],
    [False, False],
    [True, False],
    [True, False],
    [False, True],
    [False, True],
    [False, False],
    [False, False]]],
  ['regression: O valve season change',
   ['O', ['cool', 'cool', None, 'heat', 'heat', 'cool']],
   [[False, True], [True, True], [False, True], [False, False], [True, False], [False, True]]],
  ['regression: first call heat on O',
   ['O', ['heat', 'heat', None, 'cool']],
   [[True, False], [True, False], [False, False], [False, True]]],
  ['regression: first call cool on B',
   ['B', ['cool', None, 'cool', 'heat']],
   [[True, False], [False, False], [True, False], [False, True]]],
  ['regression: scenario 2',
   ['B', ['heat', 'cool', 'heat', None, 'cool', 'heat', None, 'heat', None, 'cool', None]],
   [[False, True],
    [False, False],
    [False, True],
    [False, True],
    [False, False],
    [False, True],
    [False, True],
    [True, True],
    [False, True],
    [False, False],
    [False, False]]],
  ['regression: scenario 3',
   ['B', [None, 'heat', None, None, None, None, 'cool', 'heat', 'heat', None]],
   [[False, False],
    [False, True],
    [False, True],
    [False, True],
    [False, True],
    [False, True],
    [False, False],
    [False, True],
    [True, True],
    [False, True]]],
  ['regression: scenario 4',
   ['B', ['heat', 'cool', 'cool', 'heat', 'heat', None, 'heat']],
   [[False, True], [False, False], [True, False], [False, True], [True, True], [False, True], [True, True]]]],
 [['regression: first call heat on O',
   ['O', ['heat', 'heat', None, 'cool']],
   [[True, False], [True, False], [False, False], [False, True]]],
  ['regression: scenario 1',
   ['B', ['cool', 'heat', 'heat', 'cool', 'cool', None, 'cool', 'heat', 'heat', None, None, 'heat']],
   [[True, False],
    [False, True],
    [True, True],
    [False, False],
    [True, False],
    [False, False],
    [True, False],
    [False, True],
    [True, True],
    [False, True],
    [False, True],
    [True, True]]],
  ['regression: O valve season change',
   ['O', ['cool', 'cool', None, 'heat', 'heat', 'cool']],
   [[False, True], [True, True], [False, True], [False, False], [True, False], [False, True]]],
  ['regression: B valve idle hold',
   ['B', ['heat', None, 'heat']],
   [[False, True], [False, True], [True, True]]],
  ['regression: first call cool on B',
   ['B', ['cool', None, 'cool', 'heat']],
   [[True, False], [False, False], [True, False], [False, True]]],
  ['regression: scenario 2',
   ['O', [None, 'cool', 'heat', 'cool', 'heat', 'heat']],
   [[False, False], [False, True], [False, False], [False, True], [False, False], [True, False]]],
  ['regression: scenario 3',
   ['B', ['cool', 'heat', None, None, None, 'heat', 'heat', 'cool']],
   [[True, False],
    [False, True],
    [False, True],
    [False, True],
    [False, True],
    [True, True],
    [True, True],
    [False, False]]],
  ['regression: scenario 4',
   ['O', ['heat', 'heat', 'heat', 'heat', 'heat', 'cool', None, 'cool', 'cool', None]],
   [[True, False],
    [True, False],
    [True, False],
    [True, False],
    [True, False],
    [False, True],
    [False, True],
    [True, True],
    [True, True],
    [False, True]]]],
 [['regression: first call cool on B',
   ['B', ['cool', None, 'cool', 'heat']],
   [[True, False], [False, False], [True, False], [False, True]]],
  ['regression: scenario 7',
   ['B', ['heat', 'heat', None, None, 'cool', None, 'cool', None, 'cool', None, None, None, 'heat', 'cool']],
   [[False, True],
    [True, True],
    [False, True],
    [False, True],
    [False, False],
    [False, False],
    [True, False],
    [False, False],
    [True, False],
    [False, False],
    [False, False],
    [False, False],
    [False, True],
    [False, False]]],
  ['regression: O valve season change',
   ['O', ['cool', 'cool', None, 'heat', 'heat', 'cool']],
   [[False, True], [True, True], [False, True], [False, False], [True, False], [False, True]]],
  ['regression: B valve idle hold',
   ['B', ['heat', None, 'heat']],
   [[False, True], [False, True], [True, True]]],
  ['regression: first call heat on O',
   ['O', ['heat', 'heat', None, 'cool']],
   [[True, False], [True, False], [False, False], [False, True]]],
  ['regression: scenario 1',
   ['O', ['heat', 'cool', None, 'cool', None, None, 'cool']],
   [[True, False], [False, True], [False, True], [True, True], [False, True], [False, True], [True, True]]],
  ['regression: scenario 2',
   ['B', ['cool', 'cool', 'heat', None, 'cool', 'cool', None, 'cool']],
   [[True, False],
    [True, False],
    [False, True],
    [False, True],
    [False, False],
    [True, False],
    [False, False],
    [True, False]]],
  ['regression: scenario 3',
   ['O', ['cool', 'cool', None, 'heat', 'heat', 'heat', 'cool', 'heat', None, 'heat', None, 'heat']],
   [[False, True],
    [True, True],
    [False, True],
    [False, False],
    [True, False],
    [True, False],
    [False, True],
    [False, False],
    [False, False],
    [True, False],
    [False, False],
    [True, False]]]],
 [['regression: scenario 1',
   ['O', ['heat', None, 'cool', None, 'heat', 'cool', 'heat', 'cool', None, None, None]],
   [[True, False],
    [False, False],
    [False, True],
    [False, True],
    [False, False],
    [False, True],
    [False, False],
    [False, True],
    [False, True],
    [False, True],
    [False, True]]],
  ['regression: scenario 7',
   ['B', ['heat', 'heat', 'cool', None, 'cool', 'heat', 'cool', 'heat', 'heat', 'cool', None]],
   [[False, True],
    [True, True],
    [False, False],
    [False, False],
    [True, False],
    [False, True],
    [False, False],
    [False, True],
    [True, True],
    [False, False],
    [False, False]]],
  ['regression: O valve season change',
   ['O', ['cool', 'cool', None, 'heat', 'heat', 'cool']],
   [[False, True], [True, True], [False, True], [False, False], [True, False], [False, True]]],
  ['regression: B valve idle hold',
   ['B', ['heat', None, 'heat']],
   [[False, True], [False, True], [True, True]]],
  ['regression: first call heat on O',
   ['O', ['heat', 'heat', None, 'cool']],
   [[True, False], [True, False], [False, False], [False, True]]],
  ['regression: first call cool on B',
   ['B', ['cool', None, 'cool', 'heat']],
   [[True, False], [False, False], [True, False], [False, True]]],
  ['regression: scenario 2',
   ['B', [None, None, None, None, 'cool', None, 'heat', 'cool', None]],
   [[False, False],
    [False, False],
    [False, False],
    [False, False],
    [True, False],
    [False, False],
    [False, True],
    [False, False],
    [False, False]]],
  ['regression: scenario 3',
   ['O', ['heat', 'cool', 'cool', 'heat', 'heat', None, 'heat', None, 'heat', 'heat', 'cool', 'cool']],
   [[True, False],
    [False, True],
    [True, True],
    [False, False],
    [True, False],
    [False, False],
    [True, False],
    [False, False],
    [True, False],
    [True, False],
    [False, True],
    [True, True]]]]]
for label, args, expected in fixtures[N-1]:
    check(label, solve(*args), expected)
print(json.dumps({"observations": observations, "passed": all(x["passed"] for x in observations)}, ensure_ascii=False))
raise SystemExit(0 if all(x["passed"] for x in observations) else 1)
Boundary fixtureActualExpectedOutcome
regression: O valve season change[[False, True], [True, True], [False, True], [False, False], [True, False], [False, True]][[False, True], [True, True], [False, True], [False, False], [True, False], [False, True]]Passed
regression: B valve idle hold[[True, False], [False, False], [True, False]][[False, True], [False, True], [True, True]]Failed
regression: first call heat on O[[True, False], [True, False], [False, False], [False, True]][[True, False], [True, False], [False, False], [False, True]]Passed
regression: first call cool on B[[False, True], [False, True], [True, True], [False, False]][[True, False], [False, False], [True, False], [False, True]]Failed
regression: scenario 1[[False, True], [False, False], [True, False], [False, False], [False, False], [False, True], [True, True], [False, False], [True, False], [True, False], [True, False]][[True, False], [False, True], [True, True], [False, True], [False, True], [False, False], [True, False], [False, True], [True, True], [True, True], [True, True]]Failed
regression: scenario 2[[True, False], [True, False], [False, True], [True, True], [False, False], [False, False], [True, False], [False, True], [False, False], [True, False], [False, True], [False, True], [False, False], [False, True]][[False, True], [True, True], [False, False], [True, False], [False, True], [False, True], [True, True], [False, False], [False, True], [True, True], [False, False], [False, False], [False, True], [False, False]]Failed
regression: scenario 3[[False, True], [True, True], [True, True], [False, False], [False, False], [False, False], [True, False], [False, True], [False, False], [True, False], [False, False], [True, False], [True, False]][[False, True], [True, True], [True, True], [False, False], [False, False], [False, False], [True, False], [False, True], [False, False], [True, False], [False, False], [True, False], [True, False]]Passed
regression: scenario 4[[False, False], [True, False], [False, True], [True, True], [True, True], [True, True], [False, False], [True, False], [False, False], [False, True]][[False, False], [False, True], [False, False], [True, False], [True, False], [True, False], [False, True], [True, True], [False, True], [False, False]]Failed

SHA-256 / 3c46195d470a48e351941cf4e3bfe162cf4b17c339a4261b399a675b34e7a517

3 / The verified repair

Exit 0
"""Failure Map reference implementation. Python standard library only."""
import json

N = 1
observations = []
def solve(valve_type, samples):
    valve = False
    out = []
    for call in samples:
        if call is None:
            out.append([False, valve])
            continue
        want = (call == 'cool') if valve_type == 'O' else (call == 'heat')
        changed = want != valve
        valve = want
        out.append([not changed, valve])
    return out
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
fixtures = [[['regression: O valve season change',
   ['O', ['cool', 'cool', None, 'heat', 'heat', 'cool']],
   [[False, True], [True, True], [False, True], [False, False], [True, False], [False, True]]],
  ['regression: B valve idle hold',
   ['B', ['heat', None, 'heat']],
   [[False, True], [False, True], [True, True]]],
  ['regression: first call heat on O',
   ['O', ['heat', 'heat', None, 'cool']],
   [[True, False], [True, False], [False, False], [False, True]]],
  ['regression: first call cool on B',
   ['B', ['cool', None, 'cool', 'heat']],
   [[True, False], [False, False], [True, False], [False, True]]],
  ['regression: scenario 1',
   ['B', ['cool', 'heat', 'heat', None, None, 'cool', 'cool', 'heat', 'heat', 'heat', 'heat']],
   [[True, False],
    [False, True],
    [True, True],
    [False, True],
    [False, True],
    [False, False],
    [True, False],
    [False, True],
    [True, True],
    [True, True],
    [True, True]]],
  ['regression: scenario 2',
   ['B',
    ['heat',
     'heat',
     'cool',
     'cool',
     'heat',
     None,
     'heat',
     'cool',
     'heat',
     'heat',
     'cool',
     None,
     'heat',
     'cool']],
   [[False, True],
    [True, True],
    [False, False],
    [True, False],
    [False, True],
    [False, True],
    [True, True],
    [False, False],
    [False, True],
    [True, True],
    [False, False],
    [False, False],
    [False, True],
    [False, False]]],
  ['regression: scenario 3',
   ['O', ['cool', 'cool', 'cool', 'heat', None, None, 'heat', 'cool', 'heat', 'heat', None, 'heat', 'heat']],
   [[False, True],
    [True, True],
    [True, True],
    [False, False],
    [False, False],
    [False, False],
    [True, False],
    [False, True],
    [False, False],
    [True, False],
    [False, False],
    [True, False],
    [True, False]]],
  ['regression: scenario 4',
   ['B', [None, 'heat', 'cool', 'cool', 'cool', 'cool', 'heat', 'heat', None, 'cool']],
   [[False, False],
    [False, True],
    [False, False],
    [True, False],
    [True, False],
    [True, False],
    [False, True],
    [True, True],
    [False, True],
    [False, False]]]],
 [['regression: B valve idle hold',
   ['B', ['heat', None, 'heat']],
   [[False, True], [False, True], [True, True]]],
  ['regression: scenario 1',
   ['B', [None, None, 'heat', None, 'cool', 'cool', 'cool', 'heat', None, 'cool', None]],
   [[False, False],
    [False, False],
    [False, True],
    [False, True],
    [False, False],
    [True, False],
    [True, False],
    [False, True],
    [False, True],
    [False, False],
    [False, False]]],
  ['regression: O valve season change',
   ['O', ['cool', 'cool', None, 'heat', 'heat', 'cool']],
   [[False, True], [True, True], [False, True], [False, False], [True, False], [False, True]]],
  ['regression: first call heat on O',
   ['O', ['heat', 'heat', None, 'cool']],
   [[True, False], [True, False], [False, False], [False, True]]],
  ['regression: first call cool on B',
   ['B', ['cool', None, 'cool', 'heat']],
   [[True, False], [False, False], [True, False], [False, True]]],
  ['regression: scenario 2',
   ['B', ['heat', 'cool', 'heat', None, 'cool', 'heat', None, 'heat', None, 'cool', None]],
   [[False, True],
    [False, False],
    [False, True],
    [False, True],
    [False, False],
    [False, True],
    [False, True],
    [True, True],
    [False, True],
    [False, False],
    [False, False]]],
  ['regression: scenario 3',
   ['B', [None, 'heat', None, None, None, None, 'cool', 'heat', 'heat', None]],
   [[False, False],
    [False, True],
    [False, True],
    [False, True],
    [False, True],
    [False, True],
    [False, False],
    [False, True],
    [True, True],
    [False, True]]],
  ['regression: scenario 4',
   ['B', ['heat', 'cool', 'cool', 'heat', 'heat', None, 'heat']],
   [[False, True], [False, False], [True, False], [False, True], [True, True], [False, True], [True, True]]]],
 [['regression: first call heat on O',
   ['O', ['heat', 'heat', None, 'cool']],
   [[True, False], [True, False], [False, False], [False, True]]],
  ['regression: scenario 1',
   ['B', ['cool', 'heat', 'heat', 'cool', 'cool', None, 'cool', 'heat', 'heat', None, None, 'heat']],
   [[True, False],
    [False, True],
    [True, True],
    [False, False],
    [True, False],
    [False, False],
    [True, False],
    [False, True],
    [True, True],
    [False, True],
    [False, True],
    [True, True]]],
  ['regression: O valve season change',
   ['O', ['cool', 'cool', None, 'heat', 'heat', 'cool']],
   [[False, True], [True, True], [False, True], [False, False], [True, False], [False, True]]],
  ['regression: B valve idle hold',
   ['B', ['heat', None, 'heat']],
   [[False, True], [False, True], [True, True]]],
  ['regression: first call cool on B',
   ['B', ['cool', None, 'cool', 'heat']],
   [[True, False], [False, False], [True, False], [False, True]]],
  ['regression: scenario 2',
   ['O', [None, 'cool', 'heat', 'cool', 'heat', 'heat']],
   [[False, False], [False, True], [False, False], [False, True], [False, False], [True, False]]],
  ['regression: scenario 3',
   ['B', ['cool', 'heat', None, None, None, 'heat', 'heat', 'cool']],
   [[True, False],
    [False, True],
    [False, True],
    [False, True],
    [False, True],
    [True, True],
    [True, True],
    [False, False]]],
  ['regression: scenario 4',
   ['O', ['heat', 'heat', 'heat', 'heat', 'heat', 'cool', None, 'cool', 'cool', None]],
   [[True, False],
    [True, False],
    [True, False],
    [True, False],
    [True, False],
    [False, True],
    [False, True],
    [True, True],
    [True, True],
    [False, True]]]],
 [['regression: first call cool on B',
   ['B', ['cool', None, 'cool', 'heat']],
   [[True, False], [False, False], [True, False], [False, True]]],
  ['regression: scenario 7',
   ['B', ['heat', 'heat', None, None, 'cool', None, 'cool', None, 'cool', None, None, None, 'heat', 'cool']],
   [[False, True],
    [True, True],
    [False, True],
    [False, True],
    [False, False],
    [False, False],
    [True, False],
    [False, False],
    [True, False],
    [False, False],
    [False, False],
    [False, False],
    [False, True],
    [False, False]]],
  ['regression: O valve season change',
   ['O', ['cool', 'cool', None, 'heat', 'heat', 'cool']],
   [[False, True], [True, True], [False, True], [False, False], [True, False], [False, True]]],
  ['regression: B valve idle hold',
   ['B', ['heat', None, 'heat']],
   [[False, True], [False, True], [True, True]]],
  ['regression: first call heat on O',
   ['O', ['heat', 'heat', None, 'cool']],
   [[True, False], [True, False], [False, False], [False, True]]],
  ['regression: scenario 1',
   ['O', ['heat', 'cool', None, 'cool', None, None, 'cool']],
   [[True, False], [False, True], [False, True], [True, True], [False, True], [False, True], [True, True]]],
  ['regression: scenario 2',
   ['B', ['cool', 'cool', 'heat', None, 'cool', 'cool', None, 'cool']],
   [[True, False],
    [True, False],
    [False, True],
    [False, True],
    [False, False],
    [True, False],
    [False, False],
    [True, False]]],
  ['regression: scenario 3',
   ['O', ['cool', 'cool', None, 'heat', 'heat', 'heat', 'cool', 'heat', None, 'heat', None, 'heat']],
   [[False, True],
    [True, True],
    [False, True],
    [False, False],
    [True, False],
    [True, False],
    [False, True],
    [False, False],
    [False, False],
    [True, False],
    [False, False],
    [True, False]]]],
 [['regression: scenario 1',
   ['O', ['heat', None, 'cool', None, 'heat', 'cool', 'heat', 'cool', None, None, None]],
   [[True, False],
    [False, False],
    [False, True],
    [False, True],
    [False, False],
    [False, True],
    [False, False],
    [False, True],
    [False, True],
    [False, True],
    [False, True]]],
  ['regression: scenario 7',
   ['B', ['heat', 'heat', 'cool', None, 'cool', 'heat', 'cool', 'heat', 'heat', 'cool', None]],
   [[False, True],
    [True, True],
    [False, False],
    [False, False],
    [True, False],
    [False, True],
    [False, False],
    [False, True],
    [True, True],
    [False, False],
    [False, False]]],
  ['regression: O valve season change',
   ['O', ['cool', 'cool', None, 'heat', 'heat', 'cool']],
   [[False, True], [True, True], [False, True], [False, False], [True, False], [False, True]]],
  ['regression: B valve idle hold',
   ['B', ['heat', None, 'heat']],
   [[False, True], [False, True], [True, True]]],
  ['regression: first call heat on O',
   ['O', ['heat', 'heat', None, 'cool']],
   [[True, False], [True, False], [False, False], [False, True]]],
  ['regression: first call cool on B',
   ['B', ['cool', None, 'cool', 'heat']],
   [[True, False], [False, False], [True, False], [False, True]]],
  ['regression: scenario 2',
   ['B', [None, None, None, None, 'cool', None, 'heat', 'cool', None]],
   [[False, False],
    [False, False],
    [False, False],
    [False, False],
    [True, False],
    [False, False],
    [False, True],
    [False, False],
    [False, False]]],
  ['regression: scenario 3',
   ['O', ['heat', 'cool', 'cool', 'heat', 'heat', None, 'heat', None, 'heat', 'heat', 'cool', 'cool']],
   [[True, False],
    [False, True],
    [True, True],
    [False, False],
    [True, False],
    [False, False],
    [True, False],
    [False, False],
    [True, False],
    [True, False],
    [False, True],
    [True, True]]]]]
for label, args, expected in fixtures[N-1]:
    check(label, solve(*args), expected)
print(json.dumps({"observations": observations, "passed": all(x["passed"] for x in observations)}, ensure_ascii=False))
raise SystemExit(0 if all(x["passed"] for x in observations) else 1)
Boundary fixtureActualExpectedOutcome
regression: O valve season change[[False, True], [True, True], [False, True], [False, False], [True, False], [False, True]][[False, True], [True, True], [False, True], [False, False], [True, False], [False, True]]Passed
regression: B valve idle hold[[False, True], [False, True], [True, True]][[False, True], [False, True], [True, True]]Passed
regression: first call heat on O[[True, False], [True, False], [False, False], [False, True]][[True, False], [True, False], [False, False], [False, True]]Passed
regression: first call cool on B[[True, False], [False, False], [True, False], [False, True]][[True, False], [False, False], [True, False], [False, True]]Passed
regression: scenario 1[[True, False], [False, True], [True, True], [False, True], [False, True], [False, False], [True, False], [False, True], [True, True], [True, True], [True, True]][[True, False], [False, True], [True, True], [False, True], [False, True], [False, False], [True, False], [False, True], [True, True], [True, True], [True, True]]Passed
regression: scenario 2[[False, True], [True, True], [False, False], [True, False], [False, True], [False, True], [True, True], [False, False], [False, True], [True, True], [False, False], [False, False], [False, True], [False, False]][[False, True], [True, True], [False, False], [True, False], [False, True], [False, True], [True, True], [False, False], [False, True], [True, True], [False, False], [False, False], [False, True], [False, False]]Passed
regression: scenario 3[[False, True], [True, True], [True, True], [False, False], [False, False], [False, False], [True, False], [False, True], [False, False], [True, False], [False, False], [True, False], [True, False]][[False, True], [True, True], [True, True], [False, False], [False, False], [False, False], [True, False], [False, True], [False, False], [True, False], [False, False], [True, False], [True, False]]Passed
regression: scenario 4[[False, False], [False, True], [False, False], [True, False], [True, False], [True, False], [False, True], [True, True], [False, True], [False, False]][[False, False], [False, True], [False, False], [True, False], [True, False], [True, False], [False, True], [True, True], [False, True], [False, False]]Passed

SHA-256 / fd93204e14ca4956fe4a033df62bc8cd03b05d763e44764e44ca2b0eeaf8952d

Verification & scope

A deterministic bounded teaching model of one thermostat or HVAC controller decision evaluated per sample. Temperatures are integer tenths of a degree Fahrenheit unless stated otherwise. The contract is a stipulated toy convention, not a claim of conformance to any manufacturer, ASHRAE guideline or code. This reproducer isolates one failure mechanism. Results cover the supplied fixtures. Variants within a family share a test contract and should remain grouped when constructing evaluation splits. Related mechanisms with a shared evaluation_group must also remain together; these controlled models are not independent production incidents.

Observations recorded using Python 3.12.14 at 2026-09-29T14:51:49.076773+00:00.

Case digest / d48048c77d5efaeed9a3a0c5c499f18692e67f7fb86b3cf0e47b0a257b982210