Worcester GR4700iW C Installation And Maintenance Instructions

Fault finding and diagnosis
77
Greenstar 4000 – 6 720 891 161 (2020/09)
2961 V No fan signal available ▶ Check the mains voltage to the fan.
▶ Check the fan harness for continuity and replace if required.
▶ Check the pulse width modulation (PWM).
▶ Replace the fan.
▶ Replace the PCB.
2962 V No fan signal available ▶ Check the mains voltage to the fan.
▶ Check the fan harness for continuity and replace if required.
▶ Check the pulse width modulation (PWM).
▶ Replace the fan.
▶ Replace the PCB.
2963 B The heat exchanger sensor or both supply
and heat exchanger sensors are defect
▶ Check the flow through the appliance and the system is filled.
▶ Check for air locks in the system and purge if required.
▶ Check the heat exchanger sensor (primary thermistor) and the plug connected to
temperature sensor.
▶ Check the resistance of the temperature sensor and replace if required.
▶ Check the continuity of the temperature sensor harness and replace if required.
2964 B Flow rate in heat exchanger too low ▶ Check the flow through the appliance and that the system is filled.
▶ Check for air locks in the system and purge if required.
▶ Check the heat exchanger sensor (primary thermistor) and the plug connected to the
temperature sensor.
▶ Check the resistance of the temperature sensor and replace if required.
▶ Check the continuity of the harness and replace if required.
2965 B Flow temperature too high ▶ System is not filled with water.
▶ No water flow, because CH system is closed.
▶ No water flow, because pump is not operating correctly.
▶ Check flow through appliance and system pressure.
▶ Check for air locks in the system. Purge if required.
▶ Check isolation valves.
2966 B Flow temperature rise in heat exchanger too
rapid
▶ System is not filled with water.
▶ No water flow, because CH system is closed.
▶ No water flow, because pump is not operating correctly.
▶ Check pump is operating freely check voltage to pump.
▶ Check the isolation valves.
▶ Check for air locks in the system, purge if required.
▶ Check flow through appliance and system pressure.
2967 B The temperature difference between supply
temperature sensor and temperature
sensor at heat exchanger is too large
▶ Check the flow through the appliance and that the system is filled.
▶ Check for air locks in the system and purge if required.
▶ Check the isolation valves, ensure they are open.
▶ Check the pump is operating freely and check the voltage to the pump.
▶ Check the heat exchanger sensor and the flow sensor are making correct contact with
the heat exchanger assembly/pipework.
▶ Check the heat exchanger sensor for break or short circuit, replace if required.
▶ Check the resistance of the supply sensor for break or short circuit, replace if required.
▶Check the continuity of harness, replace if required.
2968 O Refilling system pressure The auto filling function is active. The filling valve opens in order to re-pressurise the
heating system automatically.
2969 – Maximum number of refills reached The maximum number of refills has been reached.
2970 B Pressure drop in heating system too rapid Too many unexpected pressure drops within a short time period.
Cause code can appear if system is pressurised and the intelligent filling loop is activated
and the system then vented.
▶ Switch off the intelligent fill in the system menu, re-pressurise manually and vent the
system.
▶ Ensure the correct pressure. If cause code does not clear, power off appliance.
Fault code Fault category
Fault text on the display, description Remedy

Worcester GR4700iW C Specifications

General

Brand	Worcester
Model	GR4700iW C
Category	Boiler
Language	English