Functional Sequence for Thermo 90/90 S
1 Switch-on
2 Configuration Check
3 Preheating 40 sec. (cycled)
4 Fuel Dosing Pump Priming 5 - 7 sec. (1)
5 Fuel Dosing Pump / Part Load (1/4)
6 Flame Sensor Take-over
7 Stabilization Period
8 Full Load
9 Vehicle Blower ‘On’ (optional)
10 Control Range
11 Control Idle
12 Flame Sensor ‘cold’ (0)
13 Run-down completed
14 Preheating 15 - 20 sec. (cycled)
15 Fuel Dosing Pump Priming 5 - 7 sec. (1)
16 Fuel Dosing Pump / Part Load (1/4)
17 Flame Sensor Take-over
18 Stabilization Period
19 Coolant Temperature down
20 Full Load
21 Switch-off (run-down)
22 Flame Sensor ‘cold’ (0)
23 Run-down completed
A Glow Pin
B Fuel Dosing Pump
C Combustion Air Fan
D Flame Sensor
E Operation Indicator Light
F Circulation Pump
G Vehicle Blower (optional)
Setting of Control Temperatures - Thermo 90
Table Rated Temp. Control Reactivation
at Sensor Idle after
Control Idle
Minus to B6 80 °C 90 °C 75 °C
B6 not used 72 °C 82 °C 67 °C
Plus to B6 65 °C 75 °C 60 °C
On the enclosure and compact kits, B6 is connected to
minus (–).
Setting of Control Temperatures - Thermo 90 S
Connection of a plus (+) or minus (–) signal to the control
unit (connector X12, contact 7) will enable different
threshold values.
Table Rated Temp. Control Reactivation
at Sensor Idle after
Control Idle
Plus (+) 72 °C 82 °C 67 °C
Minus (–) 80 °C 90 °C 75 °C
On the enclosure and compact kits, connector X12,
contact 7 is connected to minus (–).
NOTE:
In the case of both heater models, the selected control
idle temperature of the heater should be below the
opening temperature of the engine thermostat.
3FUNCTIONAL DESCRIPTION
T
HERMO
90 / 90 S
3-2
Fig. 3-1 Functional Sequence
