Interpret LCAC error codes for Pioneer Quantum Series units

Introduction

This article explains how to interpret Light Commercial AC (LCAC) error codes for Pioneer Quantum Series systems without an onboard LED readout. Some Quantum Series systems do not possess an onboard LED display on the indoor unit.

Systems without LED displays use various light indicators to convey operations. For error codes, the light indicators will flash in certain sequences to convey the type of error.

You can interpret sequences by using this table:

Operation Lamp	Timer Lamp	Error Code Interpretation	Meaning of Error
☆ 1 time	OFF	E0	Indoor unit EEPROM parameter error
☆ 2 times	OFF	E1	Communication malfunction between indoor and outdoor units
☆ 4 times	OFF	E3	Indoor fan speed out of control
☆ 5 times	OFF	E4	Indoor room temperature sensor (T1) malfunction
☆ 6 times	OFF	E5	Evaporator coil temperature sensor (T2) malfunction
☆ 7 times	OFF	EC	Refrigerant leakage detection
☆ 8 times	OFF	EE	Water-level alarm malfunction
☆ 1 time	SOLID	F0	Current overload protection
☆ 2 times	SOLID	F1	Outdoor ambient temperature sensor (T4) malfunction
☆ 3 times	SOLID	F2	Condenser coil temperature sensor (T3) malfunction
☆ 4 times	SOLID	F3	Compressor discharge temperature sensor (T5) malfunction
☆ 5 times	SOLID	F4	Outdoor unit EEPROM parameter error
☆ 6 times	SOLID	F5	Outdoor fan speed has been out of control
☆ 7 times	SOLID	F6	Indoor coil outlet pipe sensor (Located on outdoor unit low pressure valve)
☆ 8 times	SOLID	F7	Communication malfunction between Cassette optional lift panel and the unit
☆ 9 times	SOLID	F8	Cassette optional lift panel malfunction
☆ 10 times	SOLID	F9	Cassette optional lift panel not closed
☆ 1 time	FLASHING	P0	Inverter module (IPM) malfunction
☆ 2 times	FLASHING	P1	Over-voltage or under-voltage protection
☆ 3 times	FLASHING	P2	Compressor top high temperature protection (OLP)
☆ 4 times	FLASHING	P3	Low ambient temperature cut off in heating
☆ 5 times	FLASHING	P4	Compressor drive malfunction
☆ 6 times	FLASHING	P5	Indoor units mode conflict
☆ 7 times	FLASHING	P6	Low pressure protection
☆ 8 times	FLASHING	P7	Outdoor IPM temperature sensor error

Examples

Below is an example of a CYB air handler flashing an error code pattern.

As we can observe, the sequence is:

Timer Light -> FLASHING ★
Operation Light -> 7x Flashes ★

Therefore, the code is P6 for Low Pressure (Low Refrigerant/Leak) Detection Protection.

Here is another example of an error code for CYB systems:

As we can observe, the sequence is:

Timer Light -> FLASHING ★
Operation Light -> 6x Flashes ★

Therefore, the code is P5 for Indoor Units Mode Conflict.

This usually occurs on a multi-zone setup where one indoor unit is calling for heat and another is calling for cooling. On multi-split systems, all indoor units must be working in the same mode of either all cool or all heat. The code can be eliminated by changing all units to the same mode or turning Off the conflicting unit. Using Auto mode can sometimes result in this error as well.

Interpret LCAC error codesUpdated 5 hours ago

Introduction

Examples