Ao-Smith Appliance Error Codes | Official Service Manuals
Overview
Section titled “Overview”This page contains 67+ error codes for Ao-Smith appliances, extracted directly from official Ao-Smith service manuals.
Categories
Section titled “Categories”Electric-Water-Heater
Section titled “Electric-Water-Heater”| Model | Error Codes |
|---|---|
| espt-50-200 | 4 codes |
| esrt-40-200 | 4 codes |
| esrt-50-200 | 4 codes |
Gas-Water-Heater
Section titled “Gas-Water-Heater”| Model | Error Codes |
|---|---|
| gcr-40-200 | 3 codes |
| gcr-50-200 | 4 codes |
| gpvt-50-300 | 4 codes |
Heat-Pump-Water-Heater
Section titled “Heat-Pump-Water-Heater”| Model | Error Codes |
|---|---|
| hptu-50n | 6 codes |
| hptu-66n | 5 codes |
| hptu-80n | 5 codes |
Tankless-Water-Heater
Section titled “Tankless-Water-Heater”| Model | Error Codes |
|---|---|
| nnlp-110-h-ng | 5 codes |
| nnlp-150-h-ng | 5 codes |
| nnlp-199-h-ng | 6 codes |
Water-Heater
Section titled “Water-Heater”| Model | Error Codes |
|---|---|
| esst-52-200 | 4 codes |
| gcrt-50-200 | 4 codes |
| xgs-50-200 | 4 codes |
Last Updated: March 2026