Error Codes; Fault Finding - Potterton Promax HE Store Installation & Servicing Instructions Manual

6. Fault Finding Guide
Boiler Fault Finding
NOTE: When instructed to turn the
selector to the reset position turn the
selector switch fully anticlockwise
against the spring pressure to the reset
position and hold for 5 seconds to reset
the boiler.
Table Of Error Codes
E20 Central Heating NTC Fault
E50 Flue NTC Fault
E28 Hot Water NTC Fault
Safety Thermostat Operated
E110
E119 Water Pressure Switch Not Operated
E125 Pump Fault or Primary Circulation Problem
Tank Thermistor not in Tank
E130 Flue NTC Operated
Interruption Of Power Supply while in fault mode
E131
E133 Interruption Of Gas Supply or Flame Failure
E160 Fan or Fan Wiring Fault
E193 Pre-Circulation Fault
50
Initial Fault Finding Checks
1. Check that gas, water and electrical supplies
are available at the boiler.
2. Electrical supply = 230V ~ 50 Hz.
3. CH water system pressurised to 0.5 bar
minimum when the boiler is cold.
4. The preferred minimum gas pressure is 20
mbar.
5. Carry out electrical system checks, i.e. Earth
Continuity, Resistance to Earth, Short Circuit and
Polarity with a suitable meter.
NOTE: These checks must be repeated after
any servicing or fault finding.
6. Ensure all external controls are calling for heat
and check all external and internal fuses. Before
any servicing or replacement of parts, ensure the
gas and electrical supplies are isolated.

Error Codes

1. If a fault occurs on the boiler an error code may
be shown by the facia display.
2. The codes are either two or three digit,
preceded by the letter 'E'. For example, code
E133 will be displayed by 'E1' alternating with '33'.
E50 is shown as 'E' then '50'
E20, E28 & E50 indicate faulty components or
wiring harness.
E110 shows overheat of the primary water and
E130 overheat of the flue system.
E119 is displayed when the primary water
pressure is less than 0.5 bar.
E133 indicates that the gas supply has been
interrupted, ignition has failed or the flame has
not been detected.
E125 is displayed in either of two situations:-
i) If within 15 seconds of the burner lighting the
boiler temperature has not changed by 1°.
ii) If within 10 minutes of the burner lighting the
boiler temperature twice exceeds the selected
temperature by 30°.
In these instances the pump is probably
inoperative.
3. By turning the selector switch to the 'Reset'
position for a minimum of 5 seconds when E110,
E130 & E133 are displayed it is possible to relight
the boiler.
4. If this does not have any effect, or the codes
are displayed regularly further investigation is
required.
© Baxi Heating UK Ltd 2012