60
Installation and Servicing
Section 4 - Fault Finding
FAUL
T FINDING
4.13 NO DISPLAY
Is there 230Vac to the boiler at L and N?
YES
NO
Supply power to the boiler
Is the wiring from the terminal block to the PCB
connected securely?
YES
NO
Connect the wiring from the terminal block to the
PCB securely.
Replace the PCB?
4.14 ‘F0U’ FLOW/RETURN DIFFERENTIAL GREATER THAN 50°C
Are isolation valves open?
YES
NO
Open isolation valves
Are radiator valves open?
YES
NO
Check pump wiring, if Ok replace pump
Check for system blockages
4.15 F 0C’ DHW THERMISTOR FAULT
Disconnect the DHW thermistor electrical connection.
Check the resistance using a suitable multi-meter
connected across the thermistor’s terminal pins.
Temperature
Resistance kΩ
25
o
C
9.7 – 10.3
60
o
C
2.4 – 2.6
Is the thermistor value correct?
YES
NO
Fit a new thermistor
Is there continuity between the PCB and the
Thermistor?
YES
NO
Check and replace wiring as necessary.
Replace the PCB?
NO
Open radiators valves
YES
Is pump operating?
Содержание LOGIC COMBI2 C24
Страница 62: ...62 Installation and Servicing Section 6 Benchmark to Commissioning ...
Страница 68: ...68 Notes Installation and Servicing ...
Страница 69: ...69 Notes Installation and Servicing ...