G
e5
Moderate
Goodman · HVAC Systems (AC, Furnaces & Heat Pumps)
Low Voltage Protection
Quick Answer
Error code E5 on your Goodman HVAC Systems (AC, Furnaces & Heat Pumps) means: Low Voltage Protection. This is usually fixable — see the step-by-step guide below.
Likely Causes
  1. Supply voltage to the outdoor unit below minimum operating range
  2. Undersized wiring causing voltage drop under compressor load
  3. Loose connection at the disconnect or outdoor unit terminals
  4. Utility power brown-out condition
How to Fix It
1
Measure voltage at the outdoor unit disconnect under load conditions
2
Verify voltage stays within the acceptable range (187-253VAC for 230V units)
3
Check all connections at the disconnect switch and outdoor unit terminal block
4
Verify wire gauge is adequate for the circuit length and amperage requirement
5
Contact a licensed electrician if supply voltage is consistently below the minimum threshold
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
Disconnect switch (if worn contacts)
Electrical wire (proper gauge)
Circuit breaker
Related Error Codes
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