York mini split error code F2
Indoor evaporator coil temperature sensor fault (open or short circuit).
- TypeFault
- SystemTemperature sensor
- Can I fix it?Homeowner checks, then maybe a tech
What F2 means on a York
The control board is reading the indoor evaporator coil temperature sensor as open or shorted, which means the thermistor (a small resistor whose resistance changes with temperature) is returning a value outside its normal range. The unit usually stops, or runs with the wrong output, because the control board no longer trusts that temperature reading.
On this platform, F2 is a fault: something has failed or is disconnected and needs diagnosis.
Common causes
- The indoor evaporator coil temperature thermistor has failed (they do drift and fail with age and heat cycling).
- Its plug has worked loose from the control board, or a pin has corroded.
- The sensor lead is chafed, pinched or chewed, giving an intermittent open or short.
- The control board's sensor input has failed (rare compared with the sensor itself).
How to fix it yourself
Work through the checks below first; they resolve most cases. If they do not, the repair itself may need a technician.
- Reset the system: switch the breaker (or the outdoor disconnect) off, wait a full five minutes so the boards fully discharge, then switch it back on and restart from the remote.
- If the code comes straight back after a reset, the fault is real and not a glitch.
- With power off, locate the indoor evaporator coil temperature sensor in a copper well on the evaporator coil. Follow its lead back to the board and reseat the plug firmly.
- Inspect the lead for damage along its whole length, especially where it passes through the chassis.
- If you have a multimeter, unplug the sensor and measure its resistance. A reading near zero ohms (short) or infinite (open) confirms a bad sensor. Most mini split thermistors read roughly 5 to 20 kΩ at room temperature, so a value in that range with a steady drift as you warm it in your hand means the sensor is fine and the board is the suspect.
- Replacement thermistors are inexpensive and plug in. Match the part number from the parts list for your model.
Switch off power at the breaker before opening either unit. Capacitors in the outdoor unit hold a charge for several minutes after power is cut.
When to call a technician
Sensor swaps are a doable DIY job on most units. Call a technician if the sensor tests good and the code persists, because that points at the control board.
Which York units show F2
This page applies to York M-Series inverter-driven (DHM / DHP) and York multi-zone (DHM…CMB) units. York's own documentation lists F2 as "Indoor evaporator coil temperature sensor fault (open or short circuit)", the same definition used across the Gree platform it is built on. If your unit shows a code with a different shape (for example a four-character code, or a plain number), it is from a different table; use the lookup with your exact code.
Where York shows this code
The code shows on the indoor unit's display in place of the temperature. If the display is off, press the Light button on the remote. Some models also count out the code as indicator blinks. E codes are system protections and faults, F codes are mostly sensor faults, H codes are outdoor and compressor protections, U codes are motor and valve faults, and P codes are power-supply faults.
Other York codes
Same part of the system as F2:
F2 on other brands
The same characters do not always mean the same thing. Check the brand on your unit.
- Pioneer F2 Condenser coil temperature sensor (T3) open or short circuit / Zone B indoor coil outlet sensor (T2B) fault, shown on the outdoor display
- Blueridge F2 Indoor evaporator coil temperature sensor fault (open or short circuit) / Condenser coil temperature sensor (T3) open or short circuit
- Gree F2 Indoor evaporator coil temperature sensor fault (open or short circuit)
- Zone Air F2 Discharge temperature sensor fault protection
- Carrier F2 Condenser coil temperature sensor (T3) open or short circuit
- Heil F2 Condenser coil temperature sensor (T3) open or short circuit / Indoor evaporator coil temperature sensor fault (open or short circuit)
- ACiQ F2 Condenser coil temperature sensor (T3) open or short circuit / Discharge temperature sensor fault protection
Questions people ask
Can I reset a York F2 code myself?
Yes. Turn the system off at the breaker for five minutes, then restart it. If F2 comes back, the fault is real and needs the checks above.
Is it safe to keep running a York showing F2?
The unit will usually refuse to run, or run with reduced output, until the fault is cleared. Repeated resets do not fix anything and can mask a problem that is getting worse.
Do I need a technician for York F2?
Work through the checks below first; they resolve most cases. If they do not, the repair itself may need a technician. Sensor swaps are a doable DIY job on most units. Call a technician if the sensor tests good and the code persists, because that points at the control board.
Sources
- York M-Series Inverter-Driven Air Conditioning Units Service Manual (DHM18-42CMB21S), Troubleshooting error code tables
Updated September 2026. Codes and definitions vary by model year. If your manual disagrees with this page, your manual wins. Send a correction.