P1Daikin · VRV IV RXTQ-TA / RXTQ-TB · Heat Pump

Daikin VRV IV RXTQ-TA / RXTQ-TB error code P1

Inverter circuit capacitor high voltage

Needs attention soon

Also written as DC bus, capacitor high voltage, P1, stored voltage

Which models this applies to. Outdoor unit

What is specific to the VRV IV RXTQ-TA / RXTQ-TB platform

The RXTQ outdoor unit serves VRV indoor units over a shared communication bus, and the factory splits the code list by which unit reports it. A and C codes come from indoor units, E, F, H, J, L and P from the outdoor unit, and U and M are system or centralized controller faults. This is a commercial and light commercial multi split platform, not a residential one indoor mini split unit.

Your control board prints the code as text, for example F01 or EE3, so you read it off the display rather than counting blinks. The printed number is the fault itself, not a position in a table.

Quick answer

On Daikin VRV IV RXTQ-TA / RXTQ-TB, P1 is a fault. It means inverter circuit capacitor high voltage. A first thing to check: A supply voltage that is unstable, too high, or interrupted.

Applies to: Daikin VRV IV RXTQ-TA / RXTQ-TB; Daikin VRV IV RXTQ heat pump codes · Heat Pump
Type of code: Fault; Urgency: Needs attention soon
First safe check: Check the supply voltage at the outdoor unit and look for instability and brownouts, since a supply event is a frequent trigger.

Checked 2026-09-26

What P1 means on this model

The DC bus capacitor in the inverter circuit has charged to a voltage the drive considers abnormal. The capacitor itself is rarely the cause, so look at the power supply section, the drive and the supply voltage upstream. The bus can hold a lethal voltage after the unit is switched off.

Symptoms you will notice

Outdoor unit shows P1 and the system stops
The system will not start
The fault is intermittent and often follows a brownout
The supply voltage at the outdoor unit is unstable

Common causes

The code tells you what the control detected, not which part failed. These are the causes we see most often, roughly in order of likelihood:

A supply voltage that is unstable, too high, or interrupted
A failed inverter or power supply section producing an abnormal DC level
A failed DC link capacitor
A brownout or voltage event that momentarily overcharged the bus

What you can safely check

These are homeowner-level checks. None of them need you to open a live electrical compartment or work on gas.

Check the supply voltage at the outdoor unit and look for instability and brownouts, since a supply event is a frequent trigger.
Check whether the fault coincides with other electrical equipment starting on the same supply.

Do not do these

×Do not discharge or probe the DC bus capacitor yourself. It can hold a lethal voltage after the unit is switched off.
×Do not fit a larger supply fuse or a heavier breaker in response to this code.
×Do not keep restarting the unit on P1, because the drive is reporting an abnormal voltage on the circuit that feeds the compressor.

When to call a technician

Book a technician, do not keep resetting it

This fault will not clear on its own. Every power cycle gives the control one more failed attempt, and repeated attempts are what turn a cheap part replacement into a seized or contaminated system.

The refrigerant circuit is sealed and legally requires licensed handling. Opening it without certification releases refrigerant and can put the whole system in violation of regulation, so a low-pressure or high-pressure fault on this equipment is a call-out, not a weekend job.
If the appliance has stopped mid-cycle, is making a noise you have not heard before, or smells burnt, stop reading here and call. Those are symptoms of something the fault code does not describe well enough.

A licensed technician job. This code involves stored high voltage and is not a homeowner task.

What it costs to fix

Parts

Inverter or power supply section $500 to $1,200. DC link capacitor $100 to $300.

Labor

Two to four hours to diagnose and replace.

DIY or technician