York
6 red
LockoutPS opened 4 times this call
Intermittent draft drop. One-hour lockout.
Walk 6 red in Diagnose
5 plates — walk the one on the cabinet
First check
1 Prove inducer and the live code
Do not pull power — that clears the York TM8T active code. Write 6 red. Is the inducer spinning on this call? Silent inducer is not a pressure switch. This is Category I metal vent. There is no 96% collector or PVC trap to prime.
Expect: 120 VAC at the inducer on a heat call. Wheel turning.
If fail: 120 VAC missing → IFC / door switch / incoming power. Voltage + dead motor → inducer.
If pass: Inducer running + this code → trap, hose, switch, vent (step 2).
The rest of the walkthrough is Diagnose.
On the plates
- Same physics as 3-red — trap, hose, vent, wind — but intermittent. Watch a full call; do not just ohm a cold switch.
- Condensate backing into the collector only after several minutes.
- High-fire only? Then the high-fire hose / vent capacity is the path.
- Trap that refills, wind, hose, high-fire vent capacity.
- Wind, cold chimney, inducer wheel, hose. Not a trap siphon.
- This is Category I metal vent. There is no 96% collector or PVC trap to prime.
- Cap, liner, common-vent tables, inducer wheel, hose on the inducer housing.