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12

12 - Gas service interrupted or LP gas low

Rheem · Water Heaters

What does 12 mean?

This error code means the gas supply to the water heater has been interrupted. For propane models, it indicates the LP gas tank is running low.

Common Causes

  • Main gas supply to the house is off
  • LP gas tank is empty or nearly empty
  • Gas valve has been accidentally shut off

Repair Steps & Checklist

Click steps to track your progress.

  1. 1

    Check if other gas appliances in your home are working.

  2. 2

    If you have an LP tank, check the fuel level and refill or replace the tank if necessary.

  3. 3

    Contact your gas utility company to ensure gas service is active.

  4. 4

    Contact a qualified service technician if the issue persists.

Browse all codes in this manual (70)
Verified technical data. Last updated: April 2026

Related Faults

1111 - Gas shut-off valve is not fully open13Hot and cold water lines reversed1414 - Water heater is overheating
Source: Rheem Water Heaters
Open Manual (Page 77)Search more codes in this manual