Suburban Aire SA40 - Rear detail

1. Exhaust
2. Fresh Air Intakes
3. Electronic Gas Valve
4. Capacitor
5. Module Board
6. Transformer
7. Blower Housing
8. Manifold Assembly
9. 90° Street Elbow
10. Sail Switch

The Fresh Air Intakes(2) uses fresh air from the outside for cumbustion.

The Sail Switch(10) makes sure that the blowers are blowing enough air across the heat exchanger. If the blowers are obstructed or not running at their full potential the unit may not operate.