Fault Finding And Diagnosis; Fault Finding - Worcester GREENSPRING CWi47 Installation And Operating Instructions Manual

11

FAULT FINDING AND DIAGNOSIS

11.1 FAULT FINDING

To remove error code from the display,
press the reset button.
Display Cause
Fault in the flue temperature
sensor.
Temperature above 110 °C
inside the cabinet.
Flue gas temperature sensor -
Fault occurs if sensor is
disconnected or in short
circuit or appliance selection
in "P7" mode is not correct.
Burner backflow temperature
sensor defect - fault occurs if
sensor is disconnected or in
short circuit.
Outlet temperature sensor
fault (Temperature below 0°C
or above 98°C).
Tab. 27
* By qualified registered gas engineer only.
6 720 646 322 (2012/05)
Solution
1. Check continuity of the flue temperature sensor (normaly
closed).*
2. Check for flue gas tightness around the top and bottom
seals of heat exchanger, use mirror to check around the rear as
well as the viewing window.
3. Check flue requirements are met. Long flue lengths, flueing
with more than three elbows, blocked flue gas pipe or cross
ventilation may cause this fault.
4. Check that flue temperature sensor connector and spade
connections are secure.*
5. Disconnect water heater from electrical supply and check
the wiring harness connections on the control board.
1. Check flue gas temperature sensor connection (
pos. 9).
2. Check sensor (< 100 ohm = short circuit).*
3. Check "P7" mode: The correct selection is "Cd".*
1. Check burner backflow temperature sensor connection (
Fig. 2, pos. 13).
2. Replace flue gas temperature sensor.*
1. Check red wire connections at hot water temperature
sensor. Clean terminals. If badly corroded, replace sensor and
wire harness.*
2. Sensor may trip if water temperature drops below 0°C to
protect heater from freezing conditions. Any damage caused by
freezing conditions is not covered by the warranty.
3. Clean the water filter, and any dirt in the taps and also the
water filters in the installation.
4. In areas where water has a high mineral content, periodic
descaling may be necessary.*
5. Check sensor.
FAULT FINDING AND DIAGNOSIS
Fig. 2,
51