e7
Moderate
York · HVAC Systems (AC, Furnaces, Heat Pumps & Thermostats)
Communication Error Between Indoor and Outdoor Units
Quick Answer
Error code E7 on your York HVAC Systems (AC, Furnaces, Heat Pumps & Thermostats) means: Communication Error Between Indoor and Outdoor Units. This is usually fixable — see the step-by-step guide below.
Likely Causes
How to Fix It
1
Verify all communication wiring connections are secure at both indoor and outdoor terminal blocks
2
Test the communication wire for continuity on all conductors between the two units
3
Confirm the wiring matches the installation diagram exactly
4
Inspect the wire run for physical damage or deterioration
5
If wiring is intact, a licensed HVAC technician should test the control boards at both units
Pro Tip
This fix requires some technical knowledge. If you're unsure about any step, consider contacting support or a qualified technician.
Parts You May Need
Communication wire
Indoor control board
Outdoor control board
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