Troubleshooting; Temperature Related Faults; Room Thermostat/Programmer Related Faults; Room Thermostat - Worcester Greenstar Comfort I RF Installation And Operating Instructions Manual

7

Troubleshooting

7.1

Temperature related faults

Problem
The required room
temperature has not been
achieved.
The room temperature is higher
that the set value
7.2

Room thermostat/Programmer related faults

7.2.1 Room thermostat

Faults are displayed alternating with the current room temperature.
Fault Cause
code code Problem
A21 1001 No RF signal
A22 1002 No RF signal or pairing
fault
A23 1003 Room stat internal sensor
failure
A24 1004 Remote RF unit has a fault Another room thermostat in the system has a
A27 1007 Unable to communicate
with boiler's EMS bus
A28 1008 Not paired
Blank display or low battery symbol

7.2.2 Programmer/Receiver

Faults will be display alternating between the fault code and the cause code
Fault Cause
code code Problem
A21 1001 No RF signal
A22 1002 No RF signal or pairing fault
A24 1004 Remote RF unit has a fault
A27 1007 Unable to communicate with
boiler's EMS bus
A28 1008 Not paired
Blank display
Comfort I– 6720810964 (2014/07)
Cause
Airlock
Low system pressure
Time program
Flow temperature
Thermostat valve in reference room
Check the Room thermostat location
refer to section 3.5
Description
All units powered and not showing low
battery symbol
All units powered and not showing low
battery symbol
Internal room temperature sensor out of
valid range
problem
Boiler is EMS compatible but no
communication
Unit is not paired
Batteries are spent
Description
All units powered and not showing low
battery symbol
All units powered and not showing low
battery symbol
A Room thermostat in the system has
a fault
Boiler is EMS compatible but no
communication
Unit is not paired
No connection to EMS bus
Remedy
Bleed the radiators and vent the heating system.
Top up the system pressure via the filling link
Is the heating on for long enough
Set a higher flow temperature
Operate the TRV to ensure that it does not stick
Fully open the TRV
Move the Room thermostat to a more suitable location
Check signal strength and reposition
Room thermostat for better signal
Repeat pairing
Replace RF Room thermostat
Check other room thermostats within
the system for fault codes
Replace EMS interface
Unpair and pair all
Replace batteries
Check signal strength and reposition Room
thermostat for better signal
Repeat pairing
Check room thermostats within the system
for fault codes
Replace EMS interface
Unpair and pair all
Ensure EMS unit is connected properly
Troubleshooting
Remedy
Remedy
19