Errors

• - select type -
• ATI-110C-N
• ATI-240H-N Indoor (T-H3J-DV)
• ATI-240H-N Outdoor (T-H3J-OS)
• ATI-310C-N
• ATI-340H-N Indoor (T-H3S-DV)
• ATI-340H-N Outdoor (T-H3S-OS)
• ATI-510C-N
• ATI-540H-N Indoor (T-H3-DV)
• ATI-540H-N Outdoor (T-H3-OS)
• GDHE-75

• - select code -
• 031
• 101
• 111
• 121
• 311
• 321
• 331
• 341
• 391
• 441
• 510
• 551
• 611
• 651
• 701
• 711
• 721
• 741
• 751
• 761
• 941
• 991

Boiler type ATI-340H-N Indoor (T-H3S-DV)

Error code 751

Cause:

Miscommunication between water heater and temperature controller (Indoor models only)

Solution:

• Inspect the connections between the water heater and temperature controller.
• Check the power supply of the water heater