DeDietrich MODULENS O PRO Manual

Labo 1/2 IT2721-en
Technical Information
MODULENS O PRO
PFC 45 - PFC 60 - PFC 90 – PFC 120
Diagnostic aid
JS N° IT2721-en 07/07/2023
1. Symptom
The boiler remains on standby:
- A heating demand is present (symbol is blinking)
- No fault displayed.
- The boiler doesn't start
2. Solution
1) Switch the boiler off and on again (ON/OFF switch)
2) If the default E07.12 is displayed:
- the safety thermostat is activated,
- the RV safety control box displays a E2 fault, stops the boiler, but does not
immediately transmit the fault to the boiler control panel (no error displayed). The
display of the error only appears after switching the boiler off and on again.
RV Safety control box
EN
Symbol is blinking:
Boiler in demand

Labo 2/2 IT2721-en
3) Solve the E07.12 fault:
3.1 Carry out the checks indicated in the instruction manual to remove the fault:
E07.12
STB activated
No water circulation
•Vent the air from the heating system
•Check the circulation (direction, pump,
valves)
•Check the water pressure
•Check the cleanliness of the heating
body
Poor connection
•Check the wiring of the safety
thermostat.
•Check that the safety thermostat has
been correctly installed, replace it if
necessary.
3.2 Clear the error
- Switch the boiler off and back on:
The boiler starts up again automatically when the cause of the error has been removed.
or
- clear the error manually by pressing button .
3. Concerned appliances
•Only RV safety boxes with a software version between 117 (fitted from July 2017) and
120 (fitted until April 2021) have this fault.
•RV safety boxes with software version 121, fitted on appliances since May 2021, no
longer have this problem.
4. Spare parts
Preventive replacement of the safety box is not necessary.
5. Accessing the RV safety box
To check the software version of the RV safety control box :
1. Remove the boiler top panel
2. Check the label sticked on the safety box: in the example below the software version is
120.