The Propex heaters were designed to be safe and reliable sources of heat for your vehicle. Being mounted in a non-stationary vehicle presents it's own challenges as the units are subject to vibration and exposure to all types of environments. Because of this, Propex designers err on the side of caution and create distinct operating parameters for the heating units. If the heater's electronic protection system senses that the unit is outside safe operating parameters it will show a fault code and shut down for inspection.
The two-flash code is triggered by the heater's overheat sensor. Located in the heater air ducting, this sensor warns the heater's logic circuit when the temperature of the combustion chamber reaches a critical level. To minimize risk of damage to the heater or the vehicle, the sensor shuts the heater down and throws a fault code.
This code often happens when the heated air going into the cabin of the vehicle is obstructed. Check for blockages in the ducting or move anything that may have fallen in front of the outlet vent. Let the heater cool down and reset the fault code (Resetting Propex Fault Codes). Once the heater is cool, try running it again.
An overheat condition can also occur when the heat output ducting has an acute angle in its run. Though Propex sells 90-degree fitting, they should not be used within 15 inches of the heater outlet. All curves in the ducting run must be as shallow as possible.
If the two-flash code is not able to be cleared, you may have a failed heat sensor. This is not field-serviceable - please contact support@vancafe.com to initiate a repair.
NOTE: In HS2211 models, the two-flash code may be a result of water infiltration causing corrosion on the overheat sensor. The sensor will need to be replaced before the heater can be operated normally.