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48
TROUBLESHOOTING
TROUBLESHOOTING
SERVICE MODE
To enter in the service mode, unlock the buttons by simultaneously
pressing the “Lock/Unlock” and “Minus” buttons for 3 seconds. In
service mode, the “service” icon shows on the display.
While in service mode, pressing the “Plus/Minus” (SW3 & SW4)
buttons cycles between service codes. The numeric display shows
the service code for 1 second, followed by the actual measurement,
which is displayed for 3 seconds.
Example:
H06-5.00 is the service code for “H06 Blower RPM target,” and
“5.00” is the blower speed (5.00 x 1000 = 5,000 rpm).
The display continues to show the service code and the measurement
value unless the up or down arrow button is pressed to switch to
the next item.
To exit service mode, simultaneously press the “Lock/Unlock” (SW2)
and “Minus” (SW4) buttons again for 3 seconds. Also, if in service
mode and no button is pressed for 30 seconds, the unit will go back
to operation mode, with the setpoint on the display and the buttons
locked.
Table 22. Service Code Functions
Service Code
Service Functions
Range
Unit
On LCD
H01
SW code / SW revision
H01_xxx_xxx
H02
Tank temperature
0-999
°C /°F
H02_xxx
H03
Tank temperature 2
0-999
°C /°F
H03_xxx
H04
Flame current
0-9.9
uA
H04_xx
H05
Blower rpm (actual)
1.00-9.99
(x1000) rpm
H05_xxx
H06
Blower rpm (commanded)
1.00-9.99
(x1000) rpm
H06_xxx
H07
LDM Voltage
0.00-9.99
V
H07_xxx
H08
Total Heating cycles
0-999999
-
H08_xxx_xxx
H09
Total heating time
0-999999
h
H09_xxx_xxx
H10
Total Ignition failures
0-999999
-
H10_xxx_xxx
H11
Total Flame loss failures
0-999999
-
H11_xxx_xxx
H12
Error code History 1
-
-
H12_xxx_xxx
H13
Error code History 2
-
-
H13_xxx_xxx
H14
Error code History 3
-
-
H14_xxx_xxx
H15
Error code history 4
-
-
H15_xxx_xxx
H16
Error code History 5
-
-
H16_xxx_xxx
H17
Error code History 6
-
-
H17_xxx_xxx
H18
Error code History 7
-
-
H18_xxx_xxx
H19
Error code History 8
-
H19_xxx_xxx
H20
Error code History 9
-
-
H20_xxx_xxx
H21
Error code History 10
-
-
H21_xxx_xxx
OUTLET AIR PRESSURE SWITCH (OAPS)
The role of the OAPS is to detect a blocked flue outlet (blocked
vent). It is a normally closed switch that opens when the outlet vent
is partially or totally blocked. In case it opens, the heater ceases
heating mode, goes to post-purge and displays E06. Once the post-
purge is over, if heat request is still present and the OAPS is closed,
the system should restart and attempt to start a new heating cycle.
If the OAPS opens three times in less than 60 minutes since first
occurrence the heater ceases heating mode, goes to post-purge,
and displays E05. See
Error Codes
(page 50).
INTAKE AIR PRESSURE SWITCH (IAPS)
The role of the IAPS is to detect a blocked air inlet. It’s a normally
closed switch that opens when the inlet vent is partially or totally
blocked. In case it opens, the heater ceases heating mode, goes to
post-purge and displays E23. Once the post-purge is over, if heat
request is still present and the IAPS is closed, the system should
restart and attempt to start a new heating cycle. If the IAPS opens
three times in less than 60 minutes since first occurrence the heater
ceases heating mode, goes to post-purge and displays E22. See
Error Codes
(page 50).