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A125

A125 - Lower element error or relay stuck closed

Rheem · Air Conditioning

What does A125 mean?

There is an error with the lower heating element or its relay is stuck in the closed position, potentially causing continuous heating. The heater is disabled.

Common Causes

  • Heating element failure
  • Control board relay failure

Repair Steps & Checklist

Click steps to track your progress.

  1. 1

    Turn off power to the unit at the breaker.

  2. 2

    Check the resistance of the heating element using an Ohm reading chart.

  3. 3

    If the resistance is correct, replace the control board. If not, replace the heating element.

Browse all codes in this manual (48)
Verified technical data. Last updated: April 2026

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Source: Rheem Air Conditioning
Open Manual (Page 33)Search more codes in this manual