Rover's Vikingship The Airconditioning
part two
Rover's Vikingship


This part of site is an attempt to organize and add to the web resources for the Rover SD1 to form a cohesive and easily usable guide for those of us without easy access to expert repair and/or advice. It is not offered in any way as a definitive source and we take no responsibility for any errors that may exist.
Webmaster Rene Winters

The Rover SD1 Airconditioning
The Vacuum Circuit

These two actuators operate the face level and the distribution flaps.
The face level flap can adopt three positions. By applying vacuum to one or both chambers inside its actuator, the flap adopts a partially open or fully open position. With no vacuum applied, the flap is closed.
The distribution flap has only two positions. It directs air to the screen, when vacuum is applied, or to the footwells, when vented.

A third actuator, inside the blower box, operates the fresh air/recirculation flap.
When vacuum is applied, the flap adopts the recirculation position.
This water valve is also vacuum operated. It controls the flow of engine coolant through the heater. The valve is closed when vacuum is applied.

The vacuum circuit is controlled by this vacuum diverter, a routing device, or switch, connected to the mode selector.
The diverter has seven ports, which are either connected to or isolated from the vacuum supply, port F, by a moveable template.
As successive mode selections are made, the template rotates and applies vacuum to, or vents the lines to the flap actuators.
As you see here the face level flap actuator 1, is connected to ports A and B, one to each vacuum chamber. The distribution flap actuator 2, is connected to part G, and the fresh air/ recirculation flap actuator 3, to port E.
The line from port D is joined to port C through vacuum switch 1 the switch is operated by the blower speed lever. It ensures that the fresh air vent is closed by applying vacuum to the fresh air/recirculation flap actuator whenever the air conditioning is switched off.
A second vacuum switch is connected to the temperature selection lever.
In the full cold position the switch 2, applies vacuum to the water valve and stops engine coolant flowing through the heater.

In addition to its vacuum control, the temperature selection lever mechanically operates the air blend flap.
The lever is connected to the flap by this linkage.
The flap position directly relates to the position of the lever.

Airconditioning part one
Airconditioning part three



© rwp june 2003