How to fix Daikin REYQ18T7Y1B Air Conditioner ambient temperature sensor malfunction?
- JJean GordonSep 23, 2025
If the ambient temperature sensor is malfunctioning on your Daikin Air Conditioner, check the connection on the PCB or actuator.

How to fix Daikin REYQ18T7Y1B Air Conditioner ambient temperature sensor malfunction?
If the ambient temperature sensor is malfunctioning on your Daikin Air Conditioner, check the connection on the PCB or actuator.
What to do if my Daikin REYQ18T7Y1B Air Conditioner shows a low pressure malfunction?
If your Daikin Air Conditioner is showing a low pressure malfunction, first open the stop valves. Then, check the refrigerant level and recharge the unit if needed. Finally, inspect the user interface display and the transmission wiring between the outdoor and indoor units.
How to fix a Daikin REYQ18T7Y1B Air Conditioner indoor unit communication error?
If you experience an indoor unit communication error with your Daikin Air Conditioner, check the user interface connection.
How to troubleshoot a Daikin REYQ18T7Y1B with an activated high pressure switch?
If the high pressure switch is activated on your Daikin Air Conditioner, check the stop valve situation and inspect for any abnormalities in the field piping or airflow over the air-cooled coil.
What to do if my Daikin REYQ18T7Y1B has a refrigerant overcharge or stop valve closed?
If your Daikin Air Conditioner indicates a refrigerant overcharge or a closed stop valve, check the refrigerant amount and recharge the unit if necessary. Also, ensure that the stop valves are open.
How to troubleshoot Daikin Air Conditioner electronic expansion valve (lower heat exchanger)?
If you are experiencing issues with the electronic expansion valve (lower heat exchanger) (Y3E) on your Daikin Air Conditioner, check the connection on the main PCB (X23A) or the actuator.
How to troubleshoot Daikin Air Conditioner electronic expansion valve (receiver gas)?
If you are experiencing issues with the electronic expansion valve (receiver gas) (Y4E) on your Daikin Air Conditioner, check the connection on the main PCB (X25A) or the actuator.
How to troubleshoot Daikin REYQ18T7Y1B electronic expansion valve (subcool heat exchanger)?
If you are experiencing issues with the electronic expansion valve (subcool heat exchanger) (Y2E) on your Daikin Air Conditioner, check the connection on the main PCB (X22A) or the actuator.
What to do if stop valve closed during Daikin Air Conditioner system test run?
If the stop valve is closed or wrong during the system test run of your Daikin Air Conditioner, open the stop valves.
How to open a closed liquid stop valve on a Daikin Air Conditioner?
If the liquid stop valve is closed on your Daikin Air Conditioner, open the liquid stop valve.
| Model | REYQ18T7Y1B |
|---|---|
| Category | Air Conditioner |
| Cooling Capacity (kW) | 5.0 |
| Refrigerant | R32 |
| Power Supply (Indoor Unit) | 220-240V, 50Hz |
Procedures for routing and connecting refrigerant piping to outdoor and indoor units.
Guidelines and methods for checking refrigerant piping for leaks and vacuum.
Covers precautions and procedures for charging refrigerant into the system.
Details on connecting electrical wiring, including power supply and transmission wiring.
Guides on making essential field settings for system configuration using unit controls.
Important safety precautions to observe before performing commissioning tests.
A checklist of items to verify after installation before powering up the unit.
Overview of the test operation procedure and checks performed on the system.
Step-by-step instructions for performing the system test run.
Guidance on how to resolve system issues by interpreting and addressing error codes.
A comprehensive list and explanation of error codes displayed by the system.
A guide to understanding and interpreting system error codes for troubleshooting.











