INSTALLATION AND OPERATION INSTRUCTIONS
5-6
DC SERIES BOILERS / WATER HEATERS DC 15-95, DC 15-96, DC 20-125, DC 33-160
5.3 WARNINGS AND FAULTS
5.3.1 Warning Codes
During operation the controller can detect unusual situations and can take action to avoid damage to the heat
exchanger or other unsafe operations. During these situations the controller will limit the temperature and power
output of the burner, or temporarily disable operation entirely.
These warnings are shown ashing and visible on the main display, and only displayed when an unusual reading is
currently detected.
MAIN DISPLAY DISPLAY FAULT POSSIBLE SOLUTION
E1 Flue gas temperature approaching limit
• Supply water temperature too high
• Ambient temperature too high
• Check positioning of ue gas sensor
• Heat exchanger front panel loose, check bolt torque
• Check heat exchanger for contamination or debris
• Replace ue gas temperature sensor
E2 Direct DHW Tank Error - No ow
detected when enabling the external
DHW pump
• Pump failed – Replace pump
• DHW piping loop air locked – Bleed Air
• Flow Sensor / Flow Restrictor blocked – Remove and
Clean
• Flow Sensor Faulty – Replace
E3 S3 – DHW Sensor Open
• Check wiring
• HC boiler dened as DC
• Replace Sensor
E4 S3 – DHW Sensor Short
• Check wiring
• Replace Sensor
E5 S5 – Outdoor Sensor Short
• Check wiring
• Replace Sensor
E6 No pressure sensor detected (voltage
< 0.25V on orange sense wire, space
heating is disabled)
E7 Pressure sensor out of range (above
4.25Bar/47psi, space heating is disabled)
LO P Boiler loop pressure too low
• Bring the system back up to pressure
• Check pressure sensor
• Replace pressure sensor
POLE Polarity detection fault
• Switch the Line and Neutral wire on the power supply
• Check grounding
• Check for high potential on Neutral wire
• Replace controller
RF Physical stress on control board Loosen control board mounting screws