The “Blind” PCB Error
Inverter ACs are smart. The Outdoor PCB sends electrical pulses to the compressor and expects a signal back to know the exact position of the rotor. Error H6 means this feedback loop is broken.
Why it happens: Think of it like walking in the dark. If the PCB can’t “feel” where the compressor motor is, it stops sending power to avoid sending the wrong signal at the wrong time, which could damage the motor.
1 DIY Checks (Is it just a wire?)
Check Supply Voltage
Is your stabilizer showing below 190V or above 250V? Extreme voltage can confuse the position sensor. Fix your stabilizer first.
Listen for “The Try”
Stand near the outdoor unit. Does it make a “Hummm… Click” sound every few minutes? This means the PCB is trying to start the compressor, but the motor is locked.
Inspect Terminals
If you can see the compressor top, check the U, V, W wires. Are they burnt or loose? A loose clip is the #1 cause of H6.
Atlas Aircon Diagnostics
How we pinpoint the H6 Fault:
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01.
Wire Continuity Test We check the 3 wires running from the PCB to the Compressor. Rats often chew these, breaking the feedback signal.
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02.
Compressor Resistance Check We measure Ohms between U-V, V-W, and W-U. All three must be equal (Balanced). If one is different, the compressor winding is damaged.
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03.
PCB Sensor Circuit Test If the compressor checks out, the PCB itself is faulty (not reading the signal). We repair or replace the Outdoor PCB.
Estimated Repair Cost (Atlas Aircon)