Navien Air Conditioner H6 Error Code: Meaning & Safe Checks
Direct answer
What does H6 mean on a Navien air conditioner?
The official NAA Air Conditioner Installation and Operation Manual identifies H6 as abnormal discharge temperature after three p4 events within 100 minutes. This meaning is limited to the documented NAA Series R-454B unitary small air conditioner.
Before you begin
Safety first
This record preserves the manufacturer-stated air conditioner fault meaning only. Do not open panels, test live voltage, handle refrigerant, adjust gas pressure, bypass a safety device, or replace a part from the code alone.
- Photograph the complete main code and any displayed subcode before cycling power.
- Confirm the full rating-label model against the models listed in the cited manual.
- Stop use for gas odor, smoke, sparking, overheating, water leakage, or repeated breaker trips.
Does this guide apply?
- Region
- United States, Canada
- Product family
- NAA Series R-454B unitary small air conditioner
- Exact models
- NAA17V36-24K, NAA17V36-36K, NAA17V60-48K, NAA17V60-60K
- Scope note
- The cited manual explicitly covers NAA17V36-24K, NAA17V36-36K, NAA17V60-48K, NAA17V60-60K. Confirm the complete rating-label model before applying this definition.
Find the model label and official manual before ordering a part
Common paths to check
These are source-backed possibilities, not probability estimates for your specific unit.
- 01 Official manual meaning: Abnormal discharge temperature after three P4 events within 100 minutes.
Decision path
Safe checks, in order
- 1
Confirm the full display and model
Record the main code and subcode exactly as displayed, photograph the rating label, and confirm that the cited manual covers the complete model.
Expected: The complete display and rating-label model match the official manual entry.
If not resolved: Contact Navien support with the model, serial number, full code, and cited manual link.
- 2
Keep inspection external and safe
Check only for visible unsafe conditions and unobstructed user-accessible intake, outlet, filter, drain, or vent areas described for the exact model; do not remove service panels.
Expected: No unsafe external condition is present and no internal access is required.
If not resolved: Stop using the air conditioner and arrange service by a technician qualified for this equipment.
Reset and test
A user reset is not documented for this condition.
Important: No universal reset is asserted. A repeated safety, combustion, pressure, electrical, refrigerant, or communication fault requires model-qualified diagnosis.
Escalation point
Stop and arrange service when
- There is a gas or refrigerant odor, smoke, sparking, overheating, water leakage, unusual pressure noise, or repeated breaker tripping.
- The complete model, main code, or subcode does not match the cited manual.
- The official procedure requires panel removal, live electrical testing, combustion work, gas-pressure work, refrigerant handling, or bypassing a safety device.
Model-first repair planning
Components that may be involved
The items below describe the documented diagnostic path. They are not a diagnosis and do not identify a compatible replacement part without the complete model and original part number.
- No replacement part identified without model-specific diagnosis
Official sources
We paraphrase manufacturer material and show the publication scope so you can verify it.
- NAA Air Conditioner Installation and Operation Manual Navien · PDF page 35, H6 entry · accessed 2026-08-09
Reviewed by Device Fix Guide · Last source check:
Related guides for this equipment
These links share the same brand and equipment family. A related guide does not prove that the codes have the same cause on your model.
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