HeatMaster 25 C: A1003474 - 664Y7000 • B
EN
FR
NL
ES
IT
DE
PL
RU
en
43
LOCKING CODES
Codes
Description of the fault
Solution for the fault
E 25
Internal Control Fault
: CRC check error.
Turn unit off and on to resume normal operation.
E 30
Supply Sensor Shorted
: A short circuit has been detected in the boiler supply
temperature sensor circuit
1. Check supply temperature sensor and wiring harness for a short circuit.
2. If necessary replace the sensor, or the wire harness.
3. After fixing the problem, reset the appliance and resume normal operation.
E 31
Supply Sensor Open
: An open circuit has been detected in the boiler supply tem-
perature sensor circuit
1. Check supply temperature sensor, connectors and wiring harness for an open circuit.
2. If necessary replace the sensor, or the wire harness.
3. After fixing the problem reset the appliance and resume normal operation.
E 32
DHW Sensor Shorted:
A short circuit has been detected in the DHW temperature
sensor circuit
1. Check DHW temperature sensor and wiring harness for a short circuit.
2. If necessary replace the sensor, or the wire harness.
3. After fixing the problem reset the appliance and resume normal operation.
E 33
DHW Sensor Open
: An open circuit has been detected in the DHW temperature
sensor circuit
1. Check DHW temperature sensor, connectors and wiring harness for an open circuit.
2. If necessary replace the sensor, or the wire harness.
3. After fixing the problem reset the appliance and resume normal operation.
E 34
Low Voltage
: Line voltage has fallen below an acceptable operating level.
The boiler will automatically reset once line voltage returns to normal.
E 37
Low Water:
Water level has fallen below 0.7 bar.
1. Increase pressure to normal range.
2. The boiler will automatically reset once water level returns to normal.
E 43
Return Sensor Shorted
: A short circuit has been detected in the boiler return
temperature sensor circuit.
1. Check return temperature sensor and wiring harness for a short circuit.
2. If necessary replace the sensor, or the wire harness.
3. After fixing the problem, reset the appliance and resume normal operation.
E 44
Return Sensor Open
: An open circuit has been detected in the boiler return tem-
perature sensor circuit.
1. Check return temperature sensor, connectors and wiring harness for an open circuit.
2. If necessary replace the sensor, or the wire harness.
3. After fixing the problem, reset the appliance and resume normal operation.
E 45
Flue Sensor Shorted
: A short circuit has been detected in the boiler flue tempera-
ture sensor circuit
1. Check flue temperature sensor and wiring harness for a short circuit.
2. If necessary replace the sensor, or the wire harness.
3. After fixing the problem reset the appliance and resume normal operation.
E 46
Flue Sensor Open
: An open circuit has been detected in the boiler flue temperature
sensor circuit.
1. Check flue temperature sensor, connectors and wiring harness for an open circuit.
2. If necessary replace the sensor, or the wire harness.
3. After fixing the problem reset the appliance and resume normal operation.
E47
Water pressure sensor error
: Water pressure sensor is disconnected or broken
1. Check water pressure sensor, connectors and wiring harness.
2. If necessary replace the sensor, or the wire harness.
3. After fixing the problem reset the appliance and resume normal operation.
E 76
Gas pressure switch open
1. Check both the static and the dynamic gas pressures.
2. Correct condition which caused the pressure switch to open
3. Boiler will automatically reset once the pressure switch is closed.
External Limit Open
: An external automatic reset boiler limit has opened.
1. Correct condition which caused limit to open.
2. Boiler will automatically reset once external limit closes
E 77
High temperature mixing circuit
Check if the mixing valve functions correctly.
E 78
Mix circuit sensor shorted
1. Check Mix circuit temp. sensor and wiring harness for a short circuit.
2. If necessary replace the sensor, or the wire harness.
3. After fixing the problem reset the appliance and resume normal operation.
