Haier air conditioner E7 code: indoor/outdoor communication fault (split)

On split and mini-split systems, the indoor and outdoor units have stopped talking to each other. It often follows a power cut or surge, a tripped outdoor breaker, or damaged wiring between the units.

Likely causes

Listed from most to least common.

1. Power cut or surge confused the control boards
2. Outdoor unit breaker or disconnect switch turned off
3. Connecting wire between indoor and outdoor units loose or damaged
4. Rodent or weather damage to the line set wiring
5. Indoor or outdoor control board failed

How to fix the E7 code

Unplug the air conditioner or switch it off at the breaker before removing any panel or filter.

1. 1

   Step 1: Turn the system off

   Switch the AC off with the remote.

2. 2

   Step 2: Check the breakers

   Check the breaker panel for a tripped breaker for the AC. Also check the disconnect switch near the outdoor unit is on. Reset a tripped breaker once only.

3. 3

   Step 3: Reset the power

   Turn off power to the whole system at the breaker for 5 minutes, then turn it back on and restart the AC.

4. 4

   Step 4: Look at the visible wiring

   From a safe distance, look along the line set between the units for chewed, crushed or loose cable. Do not touch or open anything.

You'll need: Flashlight.

When to call a technician

If E7 returns after a power reset, or a breaker trips again, a licensed HVAC technician needs to test the connecting wiring and control boards. Do not open the outdoor unit's electrical panel.

A typical repair for this code costs $150–$600 in the US, including parts and labor. Prices vary by area and model.

Models this applies to

• Ductless mini-split and wall-mounted split ACs
• Inverter split heat pumps
• Portable air conditioners (US, 2017 and newer)

Codes can differ slightly between models. Your owner's manual is the final word and is available from Haier support.

Common questions