Manual Air Temperature Control Valve

With outside air temperature below 50-60°F (10-15°C) the control valve selection lever should be set to the "W" (winter) position. In this position, the control valve is closed to outside air and preheated air is drawn into the air cleaner from the exhaust manifold heat stove.

With outside air temperature above 50-60°F (10-15°C), the control valve should be set to the "S" (summer) position. In this position, the air control valve is closed to pre-heated air and outside air is drawn into the air cleaner.