Carrier · Status code
Carrier 59TP6C status code 52: supply-air temperature sensor open or short
Major code 52 reports the supply-air temperature (SAT) sensor circuit when one is installed. Minor 52.1 means the sensor reads open; minor 52.2 means it reads shorted.
On the control
- Code
- 52
- Minor
- 52.1 · 52.2
- Door LED
- 5 short flashes then 2 long
- Controller
- 59TP6C integrated furnace control with 3-digit LCD display and door LED
- Applies to
- Carrier Performance 96 (59TP6C)
- Manual
- 59TP6C-01SI REV A
What each minor code says, verbatim
| Display | Manufacturer wording |
|---|---|
| 52.1 | SAT - Open |
| 52.2 | SAT - Short |
A code is a condition, not a diagnosis
Open or short readings come from the sensor, its wiring or its connector, or from a sensor that was never installed but is expected by the control program. The circuit is tested with the sensor disconnected and its resistance checked against the accessory specification.
Which furnaces this applies to
Documented for Carrier 59TP6C furnaces (all nine sizes) in installation instructions 59TP6C-01SI REV A, edition 06/23. The SAT sensor is an optional accessory on this family; a furnace without the sensor fitted should not normally report 52.
Scope: Carrier 59TP6C Performance 96 furnaces with the on-board 3-digit display control. Not sure which control you have? Send us the full model number from the rating plate.
Safe things to look at first
- Read the full code on the control display through the door, including any minor digit (for example 33.2), and write it down.
- Look, without touching, for obvious conditions you can report: snow or ice at the vent terminations, water on the floor, a loaded filter, a condensate pump that is full or off.
- Note whether the furnace still heats at all, and how long it runs before the code returns.
- Note whether the furnace still heats normally; a sensor fault alone does not stop the burner.
Do not
- Do not bypass or jumper the door switch, limit switches, rollout switches or pressure switches.
- Do not open the burner compartment, disconnect tubing, or adjust the gas valve or gas pressure.
- Do not keep cycling power to force the furnace to relight; repeated resets hide the fault and can allow unburned gas to build up after ignition failures. If the code returns, stop and call.
Homeowner-safe checks (look and read only)
- Note whether the furnace still heats normally
When to call a technician
- If a sensor is fitted and the code persists
Also documented on the same controller family: Carrier Performance 97 (59TP7A).
What a technician does
- A technician checks the sensor wiring and connector, verifies whether the furnace program expects the sensor, and replaces the sensor only if it fails a resistance test.
Questions people ask
I do not have a supply-air sensor. Why does code 52 show?
If no sensor is installed, the control program may still be set to expect one, or the sensor wires may be shorted together at the control. A technician checks the program and the wiring.
Seeing code 52 on your Carrier?
Tell us the full code, the model number and whether the furnace still heats on low. BC Wide prioritizes no-heat calls across Greater Vancouver.