44 - EN
6.11
What to do in the event of a malfunction (or problem) without a malfunction alert
(troubleshooting)
Problem:
The display and fans of the unit are off.
Question
Answer
Action
1
Do you have power in the rest of the
dwelling?
Yes
Check the group switches/fuses in the fuse box.
No
Call your power supplier to report a power out.
2
Is the power in the fuse box turned on?
Yes
1. Open the semi-transparent visor.
2. Pull the cable tray cover forwards.
3. Check the power cable of the unit. (Check unit side and wall side)
4. Go to the next question.
No
Switch the group in the fuse box on or replace the fuse.
3
Is something wrong with the power
cable?
Yes
Replace or reconnect the power cable.
No
1. Access the main board as instructed in the chapter “How to gain access to
the main board”.
Be aware of the danger for electrical
shocks
2. Go to the next question.
4
Is a power signal present (230VAC) on
the main board?
Yes
1. Remove the top-section sensor connectors
2. Follow the instructions of the SENSOR_ETA ERROR / SENSOR_ODA ERROR /
SENSOR EHA ERROR / SENSOR_SUP ERROR table.
No
1. If the unit is a ComfoAir Q 350 get a F5010 fuse. Otherwise get a F5015 fuse.
2. Access the main power fuse as instructed in the chapter “How to gain access
to the main power fuse of the unit”.
3. Replace the main power fuse of the unit.
4. Follow the procedure for ending the maintenance.
5. Reset the errors as instructed in the chapter “How to reset errors”.
Problem:
The supply temperature is high in the summer.
Question
Answer
Action
1
Is the modulating bypass function set
to DISABLE?
9
Yes
Set the modulating bypass function to AUTO or OPEN.
9
No
Go to the next question.
2
Is the unit in heating season?
10
Yes
Set the limit RMOT (average outside temperature over 5 days) heat to the correct
value.
10
No
Decrease the temperature profile.
11
Problem:
The supply temperature is low in the winter.
Question
Answer
Action
1
Is the modulating bypass function set
to OPEN?
9
Yes
Set the modulating bypass function to AUTO or DISABLE.
9
No
Go to the next question.
2
Is the unit in cooling season?
10
Yes
Set the limit RMOT (average outside temperature over 5 days) cool to the correct
value.
10
No
Increase the temperature profile.
11
Problem:
The spindle has fallen out the modulating bypass actuator (bypass valve is
loose in the unit)
Action
1. Disconnect the power to the unit.
2. If needed: Remove the heat exchanger.
3. If needed: Jam the still connected modulating bypass valve.
4. Connect the power to the unit.
5. Push the spindle firmly to the opening of the modulating bypass actuator until the spindle is fixed again.
6. Disconnect the power to the unit.
7. Jam both connected modulating bypass valves.
8. Connect the power to the unit.
9. Follow the procedure for ending the maintenance.
9
You can find the modulating bypass settings in menu > MENU > TASK MENU > BYPASS
10
You can find the current season and the RMOT heat settings in menu > MENU > STATUS > SEASON DETECTION > SEASON
11
You can find the temperature profile setting in menu > MENU > TASK MENU > TEMPERATURE PROFILE
