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21
Värmebaronen MP4 G2 / MP6 G2
Troubleshooting
Work on the system which requires tools, must
only be carried out by authorised installers.
Ensure the boiler de-energised before
starting work!
No or insufficient heat
The regulation valves are limiting the system or the set point
value is too low for the boiler. Check and adjust.
Incorrect adjustment of the overflow valve. Check and adjust.
The boiler’s display and indications are turned off
Check the fuses and that the boiler’s control switch is in the
on position.
The group fuses for the boiler are triggered
The immersion heater is broken. Check by isolation testing it.
Measure between the outgoing side of the circuit board and earth.
Call an installation engineer!
Manual operation - test mode
In order to test the boiler’s functions when troubleshoot-
ing, you can control the power steps, the circulation pump
and the buzzer alarm relay manually. Manual operation is
activated in “Advanced service level”, row 23. The function is
deactivated automatically after 4 minutes.
Temperature sensor - measurement
The sensor must not be connected to the circuit board during
resistance measurement.
1
2
3
4
V
+
-
V
+
-
Boiler temperature
sensor
Outdoor temperature
sensor
7
8
Measuring points on the circuit board
Boiler temperature sensor
°C
kΩ
V
°C
kΩ
V
°C
kΩ
V
5
141.9
4.7 40 30
3.7 75
8.2 2.3
10
111.6
4.6 45 24.6 3.6 80
6.9 2
15
88.3
4.5 50 20.2 3.3 85
5.8 1.8
20
70.3
4.4 55 16.7
3.1
90
5
1.7
25
56.3
4.2 60 13.9 2.9 95
4.2 1.5
30
45.4
4.1
65 11.6
2.7 100 3.7 1.3
35
36.8
3.9 70 9.7
2.5
Outdoor temperature sensor
°C
kΩ
V
°C
kΩ
V
-40 88.7
4.5
0
8.8
2.3
-35 64.2
4.3
5
6.8
2.0
-30 47.0
4.1
10
5.4
1.7
-25
34.7
3.9
15
4.2
1.5
-20
25.9
3.6
20
3.4
1.3
-15
19.5
3.3
25
2.7
1.1
-10
14.8
3.0
30
2.2
0.9
-5
11.4
2.7
