User operation
19
MAXXfl o EVO Lite
3.8.1 Error codes (continued)
Error
Code
Error Code
Description
Diag.
Code
Notes
217
Sensor error
765
766
Short circuit of Ionisation circuit. Check operation of ionisation probe using pa-
rameter 8329 (menu - Diagnostics heat generation). Ionisation probe may need
replacing. Check electrical supply to the heater and burner - pay special attention
to the earth circuit and supply.
317
Grid frequency
outside permitted
range
275
461
The frequency (Hz) of the electrical supply is outside permitted tolerance. Check
electrical supply to heater.
324
Input BX, same
sensors
110
BX sensor duplicated - Two sensor inputs have been defi ned twice with the same
sensor type (e.g. B3). Review last parameters programmed to remove duplica-
tion.
325
Input BX/exten-
sion mod, same
sensors
Any
BX expansion module 1 sensor duplicated - Two sensor inputs have been de-
fi ned twice with the same sensor type (e.g. B3). Review last parameters pro-
grammed for the expansion module to remove duplication.
327
Extension mod,
same function
Any
AGU2.5 expansion module function duplicated - check parameter setup (in “Con-
fi guration” menu)
335 /
336
Sensor input
BX21 / BX22
without function
211 /
212
A sensor has been detected connected to BX21 of the AGU2.5 expansion mod-
ule 1, but not defi ned. Defi ne the sensor using the parameters or remove the
sensor if not required.
All
other
As above except the undefi ned sensor is connected to an AGU2.5 expansion
module 1. The AGU2.5 expansion module should be defi ned as module 1 -
Check the dip switches on the front of the device is set correctly
384
Extraneous light
252
393
Ionisation current detected before whilst in standby mode. Check ionisation
current (“Diagnostics producer” parameter 8329). If there is a current present is
greater than 0.61 whilst the burner is in standby, turn off gas supply to check gas
valve is closing completely. If current is still present, remove ionisation probe and
use a screwdriver to clear the opening through the burner door before replacing
the probe and testing again.
Persistent errors may indicate that the burner is only operational for very short
periods. Try increasing the switching di
ff
erential by at least 1
O
C (parameter 5024)
to increase burner run time.
Other
Ionisation current detected during ignition phase before the gas valve is opened.
385
Mains under volt-
age
554
555
Mains voltage below 185v - check electrical supply to the appliance.
386
Fan speed toler-
ance
388
Fan outside allowed speed tolerance during standby phase
531
389
Fan outside allowed speed tolerance during pre-purge phase
374
383
384
Fan outside allowed speed tolerance during ignition phase.
375
386
Fan outside allowed speed tolerance during min modulation phase.
385
Fan outside allowed speed tolerance during max modulation phase.
532
534
382
390
Fan outside allowed speed tolerance during post-purge phase
Other
Check connections and wiring loom of the fan. Replace fan if no fault found. If
necessary use parameter 9650 Chimney drying mode to test the function of the
fan without having to operate the burner.
432
Function earth
not connected
Any
No Ignition earth, X1 / X17 not connected or earth fault. Check internal and exter-
nal earth wiring to the heater
433
Heat exchange
temperature
Any
Heat exchanger temperature is too high. Investigate all sources of overheating.
When the issue has been resolved examine the heat exchanger for damage
before putting back into operation.
NA
DHW Operating
mode locked
Any
Check to see if the remote enable link wire is fi tted or external controls wired to
these terminals are closing this circuit. To activate DHW operation this circuit
must be closed.
