T20-T30 Servuce Manual 11/07/2014
Page 14 of 18
4.6.
TROUBLESHOOTING
– DIAGNOSTIC GUIDE cont:
Action required:
1. Check that the resistance on the elements. If there is a reasonable resistance (15-
25Ω) on the
element it probably has not failed, so the wiring might be at fault.
5 FLASH CYCLE
– THERMISTOR SHORT CIRCUIT
Display pattern:
5 flashes then a short pause - repeated.
Electronic check:
This indicates that the Thermistor is measuring zero resistance. It assumes the
thermistor has failed sort circuit.
The element and inlet valve are turned OFF when this error is detected
This is a recoverable error. When the correct range of resistance is measured, normal
operation resumes.
Probable causes:
2. The thermistor has failed.
Action required:
2. Replace the thermistor.
6 FLASH CYCLE
– NOT FILLING
Display pattern:
6 flashes then a short pause - repeated.
Electronic check:
This checks that the water in the tank cools when the inlet solenoid valve is switched
on.
This is a non-recoverable error. This checks that the water in the tank is cooled by when
the inlet solenoid valve is opened. If the water pressure is within the specifications (5-
50psi), the inlet solenoid should not be on for more than a few seconds. If this water
temperature has not decreased by the required amount
(1 degree per minute), the inlet solenoid is switched off and the 6 flash cycle is
displayed.
Probable causes:
1. Mains water pressure problem or the mains water stop valve is closed.
2. Inlet solenoid valve failure.
Action required:
1. Check the mains water supply. (Note: Temporary loss of water pressure can occur in certain
sites
– particularly when various machines are plumbed to the same mains water supply.) If
the water supply is ok, reset the machine (switch the machine Off and On again). This will
reset the error and if the water supply is ok, the machine will return to normal operation.
NOTE: If the water supply is the problem, ensure that this is rectified or this error will
re-occur.
2. If there is no problem with the mains water supply, check that the inlet solenoid valve is
working.