Webasto Thermo 90 ST B Installation Manual page 16

Connection to the Vehicle Cooling System
2
4
3
Figure 12: System configured in series with rear heat exchanger in a "dual" circuit heating system.
2
4
3
Figure 13: System configured in the rear heat exchanger circuit using an optional 4-way back-check valve.
2
8
10
9
9
4
3
Figure 14: System configured with a bypass circuit within the rear heat exchanger circuit where an automated flow
control valve is installed. Bypass is required in the event the valve is closed during heater operation.
Webasto Product N.A., Inc.
2
1
2
1
2
1
7
6
5
7
6
5
7
6
5
14
Thermo 90 ST
1. Coolant supply connection
2. Vehicle heat exchangers
3. Coolant pump
4. Thermo 90 ST heater
5. Coolant return connection
6. Engine coolant pump
7. Thermostat
1. Coolant supply connection
2. Vehicle heat exchangers
3. Coolant pump
4. Thermo 90 ST heater
5. Coolant return connection
6. Engine coolant pump
7. Thermostat
4-way back-check valve
1. Coolant supply connection
2. Vehicle heat exchangers
3. Coolant pump
4. Thermo 90 ST heater
5. Coolant return connection
6. Engine coolant pump
7. Thermostat
8. Automated control valve
9. Wye connectors
10. Bypass hose 13-16mm I.D.
(1/2"- 5/8" I.D.)
www.techwebasto.com