How to fix Vertiv Liebert SRC-G Air Conditioner controller not starting?
- PPatricia AndersonSep 23, 2025
If your Vertiv Air Conditioner controller isn't starting, check the fuse on the transformer and replace it with a new 3 Amps fast blow fuse.

How to fix Vertiv Liebert SRC-G Air Conditioner controller not starting?
If your Vertiv Air Conditioner controller isn't starting, check the fuse on the transformer and replace it with a new 3 Amps fast blow fuse.
Why Vertiv Liebert SRC-G Air Conditioner does not start?
If your Vertiv Air Conditioner isn't starting, it could be due to several reasons. First, check the unit's input voltage to ensure there is power supply to the unit. Another cause might be an open circuit breaker of controller voltage; locate any short circuits and reset the circuit breaker. Lastly, a low power supply voltage could be the issue, so check for the power supply voltage at the SPD, if available.
How to fix a high pressure alarm on Vertiv Air Conditioner?
To address a high pressure alarm on your Vertiv Air Conditioner, start by checking for sufficient airflow across the condenser. Remove any debris from the coil and airflow inlet, and check the fan speed function of the control board. Also, inspect the condenser fan to ensure it is operating; check that the connections of the control board to the outdoor unit terminals are firmly connected and that the condensate pressure sensor works normally. Lastly, examine the high-pressure switch and its connections, checking its on-off condition when the power is turned off; if necessary, replace it with a high-pressure switch of the same specification.
What to do if Vertiv Liebert SRC-G Air Conditioner has no display, control buttons do not respond and unit has no output?
If your Vertiv Air Conditioner shows no display, the control buttons are unresponsive, and the unit has no output, begin by checking for low power supply voltage. Also check if the connections between the control board and control board are firmly connected.
What causes low pressure alarm on Vertiv Liebert SRC-G?
A low pressure alarm on your Vertiv Air Conditioner can be triggered by a few things. One potential cause is refrigerant leakage; check for any leaking points, fix them immediately, and then recharge the system with an adequate amount of refrigerant. Another possible cause is low outdoor ambient temperature. Also check if the outdoor unit cabling is correct; and check whether the condensate pressure sensor works normally.
What does power supply phase loss alarm mean on Vertiv Liebert SRC-G Air Conditioner?
A power supply phase loss alarm on your Vertiv Air Conditioner indicates a loss of phase in the power supply. Check if the power input line cabling is in good condition.
What does remote shutdown mean for Vertiv Air Conditioner?
Remote shutdown on your Vertiv Air Conditioner indicates that the unit has been shut down via remote control. Adjust the remote control parameters to resolve this.
What to do when Vertiv Liebert SRC-G Air Conditioner shows return air temperature sensor fault alarm?
If your Vertiv Air Conditioner displays a return air temperature sensor fault alarm, it means the return air temperature and humidity sensor has failed. Replace the return air temperature and humidity sensor.
What does low temperature alarm mean for Vertiv Liebert SRC-G?
A low temperature alarm on your Vertiv Air Conditioner often means the low temperature setpoint is unreasonable. Reset the setpoint to resolve this.
What causes no display and unresponsive buttons but normal operation on Vertiv Liebert SRC-G Air Conditioner?
If your Vertiv Air Conditioner has no display and the control buttons do not respond, but the unit operates normally, the issue might be a disconnection between the keypad and control board. Check if the connections between the keypad and control board are firmly connected.
| Brand | Vertiv |
|---|---|
| Model | Liebert SRC-G Series |
| Category | Air Conditioner |
| Language | English |
Explains the purpose and scope of the user manual for the Liebert SRC-G unit.
Defines the visual styles used in the manual for warnings, cautions, and notes.
Records the revision history and changes made to the document.
Details critical safety precautions and measures to be followed during installation and maintenance.
Introduces the Liebert SRC-G as a wall-mounted precision air conditioner for equipment rooms.
Explains the 18-digit nomenclature used to define Vertiv Liebert SRC-G series models.
Describes the key components of the indoor and outdoor units, including cabinet, coils, and fans.
Guides on how to unpack and inspect the Liebert SRC-G unit components after delivery.
Provides important considerations and recommendations for the installation of the Liebert SRC-G unit.
Outlines the steps and requirements for installing the indoor unit, including room and space considerations.
Explains the general principles and requirements for connecting the refrigeration piping for the unit.
Lists essential notes and regulations for power and control cabling, and ground connections.
Details the procedure for connecting power supply and control cables to the indoor unit.
Explains how to connect the cables to the outdoor unit's terminal block.
Lists inspection requirements for unit components before commissioning to ensure proper operation.
Describes how to perform function testing for cooling and dehumidifying modes of the unit.
Highlights the features of the microprocessor controller, including display, password protection, and communication.
Explains the control interface, including function buttons and their operations.
Details the menu structure, including alarm, setpoint, system status, and help menus.
Covers system setup, outdoor unit options, and optional functions within the controller menu.
Guides on inspecting electrical components like control boards, power boards, and connections.
Covers maintenance procedures for the indoor unit, including filter, fan, and drain pipe.
Lists monthly inspection items for system components to ensure normal function and check for wear.
Provides a guide for troubleshooting common issues like unit not starting, no cooling, and display anomalies.
Presents a visual representation of the controller's menu hierarchy and navigation flow.











