Error code
2-time flash Indoor coil or room-temperature thermistor fault
How it shows on the unit Upper operation-indicator lamp: 2 flashes followed by 2.5 seconds OFF
Applies to 16 models
MSZ-AP25VG-E1, MSZ-AP25VG-EN1, MSZ-AP35VG-E1, MSZ-AP35VG-EN1, MSZ-AP42VG-E1, MSZ-AP42VG-EN1, MSZ-AP50VG-E1, MSZ-AP50VG-EN1, MSZ-AP25VGK-E1, MSZ-AP25VGK-EN1, MSZ-AP35VGK-E1, MSZ-AP35VGK-EN1, MSZ-AP42VGK-E1, MSZ-AP42VGK-EN1, MSZ-AP50VGK-E1, MSZ-AP50VGK-EN1
What this means
An indoor coil thermistor or room-temperature thermistor is detected as open or shorted.
When to call a technician
This fault involves refrigerant, pressure, or electrical work that must be handled by a certified technician under EU F-gas rules. Do not attempt to open the refrigerant circuit, access mains wiring, or adjust pressure components yourself. Contact a qualified installer or servicer for this one.
Using Claude Code or Meta Muse? Connect HeatPump AI and ask it about 2-time flash.