PU
Gree Split AC
Severity: ModerateWhat Does This Error Mean?
PU means the startup charge circuit for the main inverter capacitor is not working. The capacitor must reach a set voltage before the inverter can run the compressor. This is almost always a board-level repair — call a technician.
Affected Models
- Gree FAIRY Series
- Gree LOMO Series
- Gree U-MATCH Series
- Gree PULAR Series
- Gree Inverter Split System
Common Causes
- Charge resistor on the drive board has burned out and cannot pre-charge the capacitor
- Main DC bus electrolytic capacitor has failed and cannot hold a charge
- Inrush current relay or SCR on the charge circuit has failed
- Drive board PCB fault preventing the charge sequence from completing
- Mains supply voltage severely unstable during startup
How to Fix It
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Turn off the AC and switch off the outdoor unit circuit breaker.
PU typically appears immediately at startup — the unit cannot run, so powering down is the right action.
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Wait 15 minutes before doing anything else.
The DC bus capacitor can hold dangerous voltage for many minutes after power-off — never rush this step.
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Check that the supply voltage at the outdoor unit is stable and within rated range.
Severely unstable mains voltage during startup can prevent the capacitor charge sequence from completing.
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Try one restart after 15 minutes. If PU returns, do not attempt further restarts.
Repeated startup attempts with a failed charge circuit can cause additional board damage.
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Call a Gree-certified technician to inspect the drive board and capacitor.
The charge resistor and capacitor are the most commonly replaced components for PU errors.
When to Call a Professional
Call a technician for PU — this is a board-level fault with no DIY fix. The DC bus capacitor holds lethal voltage for several minutes after power is removed. Only a qualified technician with proper discharge equipment should open the outdoor electrical compartment.
Frequently Asked Questions
What is the capacitor charge circuit in a Gree inverter AC?
Before the inverter can switch on, the large electrolytic capacitor on the DC bus must be slowly pre-charged through a resistor. This prevents a huge inrush current spike that would damage the rectifier. If this charging sequence fails, the unit shows PU and will not start.
Can I check the capacitor on my Gree outdoor unit myself?
No — this is dangerous without proper equipment. Even after power is removed, a large capacitor can retain enough charge to cause a serious electrical shock. Always let a qualified technician handle this.
Is PU a common Gree error code?
It is less common than sensor or communication faults but does occur, especially on units that are several years old. Capacitors have a finite lifespan and gradually lose their ability to hold charge. It is a repairable fault in the majority of cases.