An error code 13 indicates a malfunction with the optional CO alarm device. Please follow these troubleshooting steps after ensuring...

An error code 30 indicates a Thermistor – Air abnormality. Please verify that the Thermistor – Air is securely connected...

An error code 31 indicates a Thermistor – Cold Water abnormality. Please verify that the Thermistor – Cold Water is...

An error code 32 indicates a Thermistor – Hot Water abnormality. Please verify that the Thermistor – Hot Water is...

An error code 33 indicates a Thermistor – Heat Exchanger Outlet abnormality. Please verify that the Thermistor – Heat Exchanger...

An error code 35 indicates a Thermistor – Exhaust abnormality. Please verify that the Thermistor – Exhaust is securely connected...

An error code 42 indicates a Water Flow Sensor (Recirculation) abnormality. This error is triggered when the system cannot maintain...

An error code 61 indicates a Fan Motor abnormality. Please verify that the Fan Motor connected to the Wire Harness,...

An error code 63 is recirculation abnormality. Please verify that the recirculation pump connected to the Wire Harness, and that...

An error code 65 indicates a Main Water Servo abnormality. Please verify that the Main Water Servo is securely connected...

An error code 66 indicates a Bypass Water Servo abnormality. Please verify that the Bypass Water Servo is securely connected...

An error code 70 indicates a Circuit Board Abnormality. Disconnect the electrical power, then reconnect electrical power to the Unit...

An error code 72 indicates a Flame Rod circuit abnormality. This error is triggered when the Flame Rod detects a...

Troubleshooting for abnormalities due to Scale Build-up C1# If the alarm code “C1#” is flashing on the display window, it...

The Error Code 11 is an ignition failure. In other words, the unit recognizes there is a demand for hot...

An error code 12 indicates a flame loss. This means that the unit is detecting a flame, but the flame...

An error code 14 indicates a significant overheat of the heat exchanger has occurred. Much like a fuse in automotive...

The 16 error code occurs when the outlet water temperature spikes to an abnormally high value. The heater will restrict...

The error code 20 means the High Limit Switch has been triggered. This error code generally requires a hard reset...

The error code 71 indicates a malfunction in the circuit board, specifically in the Gas Valve drive circuit or its...

The 73 error code indicates a circuit board setting issue. It is triggered by the following conditions: Any changes made...

The Error Code 90 indicates an airflow or combustion abnormality. (Error Code 10 is also troubleshot with the same methods)...

An error code 94 means the exhaust temperature is too high (condensing units). One of the benefits of installing a...

An error code 29 indicates a problem draining the condensate1 from the unit. This code only applies to our high efficiency condensing models. Just...

An error code 74 indicates a BLE (Bluetooth) communication issue. This error code only appears in the error history when...

An error Code 79 indicates a Circuit Board (pump control circuit) malfunction. To troubleshoot, first try resetting the system by...

An error code 50 indicates that the unit has detected continuous water flow of at least 0.26gpm or more for...

The error code 10 indicates a combustion abnormality and is usually a precursor to the more severe error code 90....

This error code only applies to the Commercial NCC199CDV when in a multi until installation. This Error Code is displayed...

An error code 42 indicates a Water Flow Sensor (Recirculation) abnormality. This error is triggered when the system cannot maintain...