mypros+
Error code reference

Samsung Air Conditioner Error Code P419

Compressor SUMP temperature protection

Samsung codesSamsung air conditioner codes

Compressor SUMP temperature protection – SUMP temperature maintained over 95°C for 5 minutes.

First step from the service manual

Perform test operation; check if digital compressor loading/unloading performs normally via S-net.

The complete diagnostic procedure includes additional test steps, resistance specifications, wiring diagram references, and component test points.

MyPros+ Max

Get the full diagnostic procedure for P419.

  • Step-by-step tests with expected resistance, voltage, and continuity values
  • Wiring diagram references and connector pinouts from the OEM service manual
  • Verified part numbers when replacement is required
Get the full procedure

$29/month · Cancel anytime · Or $9.95 3-day pass

What P419 means on a Samsung air conditioner

Error code P419 on a Samsung air conditioner indicates a compressor SUMP temperature protection fault. The SUMP refers to the oil sump at the base of the compressor, where lubricating oil collects. When the temperature at this location exceeds 95 degrees Celsius and remains above that threshold continuously for 5 minutes, the unit triggers P419 as a protective shutdown to prevent compressor damage. This threshold exists because excessive sump temperatures indicate the compressor oil is breaking down or the compressor is operating under abnormal mechanical or thermal stress.

The digital compressor in Samsung systems uses variable loading and unloading cycles to modulate capacity. If these cycles are not performing correctly, the compressor may run at sustained high loads without adequate relief, generating excess heat that accumulates in the oil sump. The S-net communication system allows technicians to monitor compressor operation in real time, making it the primary diagnostic tool for confirming whether the loading and unloading sequence is functioning as intended.

Common contributors to this fault include inadequate refrigerant charge, restricted airflow over the condenser, a failing or blocked expansion device, or a compressor that is itself degrading internally. Ambient operating conditions above the system's rated range can also push sump temperatures past the protection threshold. The first diagnostic step is running a test operation and observing compressor loading behavior via S-net to determine whether the control system or the mechanical system is the root cause.

Source: manufacturer service documentation.

Common causes of P419

  1. 01

    Abnormal compressor loading behavior

    Wiring / connection

    If the digital compressor is not cycling between loading and unloading states correctly, it runs at excessive capacity continuously and generates heat in the oil sump. This is confirmed by monitoring compressor operation through the S-net diagnostic interface during a test run.

  2. 02

    Low or improper refrigerant charge

    Wiring / connection

    An undercharged system forces the compressor to work harder, reducing cooling of the compressor body and causing oil sump temperatures to rise. Check system pressures against the rated operating specifications for the unit.

  3. 03

    Restricted condenser airflow

    Part replacement

    Blocked condenser coils or a malfunctioning condenser fan reduce heat rejection, which raises compressor operating temperatures system-wide, including the oil sump. Inspect the condenser for debris, dirt accumulation, or fan motor failure.

  4. 04

    Expansion device restriction or failure

    Part replacement

    A clogged or faulty expansion valve reduces refrigerant flow through the system, creating abnormal pressure conditions that increase compressor workload and sump heat. Check for ice formation, abnormal pressures, or flow restrictions.

  5. 05

    Compressor internal degradation

    Part replacement

    Worn internal compressor components generate excess friction heat that accumulates in the oil sump even under normal operating conditions. If all external system checks pass and sump temperatures remain elevated, internal compressor failure is likely.

See the test procedure for each cause

Frequently asked questions about P419

What does P419 mean on a Samsung air conditioner?
P419 indicates a compressor SUMP temperature protection fault. The oil sump at the base of the compressor exceeded 95 degrees Celsius and stayed above that level for 5 continuous minutes. The unit shuts down automatically to prevent compressor damage when this threshold is reached.
Can I fix P419 myself without a technician?
Some basic checks, such as clearing debris from the condenser or ensuring the outdoor unit has adequate airflow clearance, can be done without professional tools. However, diagnosing compressor loading behavior via S-net, checking refrigerant charge, or replacing components requires specialized equipment and certification. A licensed HVAC technician should handle the full diagnosis.
Is it safe to keep running my air conditioner with a P419 error?
No. P419 is a protective fault that shuts the unit down to prevent compressor damage. Attempting to override or repeatedly reset the system while the underlying cause remains unresolved risks permanent compressor failure, which is one of the most expensive repairs possible on any air conditioning system.
Will resetting the unit clear the P419 error?
A reset may temporarily clear the fault code and allow the unit to restart, but P419 will return if the root cause is not corrected. The system is designed to re-trigger the protection whenever sump temperature exceeds 95 degrees Celsius for 5 minutes, so repeated resets without repair will not resolve the issue and may worsen compressor wear.
How much does it cost to repair a P419 error on a Samsung air conditioner?
Repair costs vary widely depending on the cause. A refrigerant recharge or condenser cleaning typically ranges from 100 to 300 dollars. Replacing an expansion valve may run 200 to 500 dollars including labor. If the compressor itself has failed, replacement costs can range from 800 to over 2,000 dollars depending on the unit size and model, making early diagnosis important.

Related Samsung air conditioner codes

All Samsung air conditioner codes
View all 572 Samsung air conditioner codes

78,000+ service manuals · 160,000+ error codes · 55+ brands

Get Started

$29/month · Cancel anytime · Or $9.95 3-day pass