Observe the safe working load limits of all lifting and blocking devices and keep a safe distance from suspended/blocked loads. Personnel may be seriously injured or killed by falling loads. Use the following procedure to defrost the cab interior:System Overview Illustration 1 g06296508 Illustration 2 g06296537The Cat ® rear entry cab AC system has two units controlled by a single controller. The main cab unit is located behind the operator seat and provides air flow for the main cab area. Refer to Illustration 1. The second unit is located below the operator seat in the riser. Refer to Illustration 2. This unit is ducted to the front left and right pillars and provides airflow directly on the operator as well as the front window for defrost/defog.Controls Illustration 3 g06295724 (A) A/C controllerBoth units are controlled by a single controller placed in the left-hand side console.Controls Illustration 4 g06295727 (B) Fan speed dial (C) Temperature dial (D) AC/Defrost switchThe AC controller contains a fan speed dial (B), temperature dial (C) and AC/Defrost switch (D). Each controls both units simultaneously. For best defrost/defog performance as well as best cooling performance the AC/Defrost switch (D) should be switched ON.Main Cab Unit Illustration 5 g06296508The main cab unit is located in the rear left of the cab directly behind the operator seat. This unit has four large vents used to heat and cool the main cabin area. These vents can be rotated and directed to best help with airflow.Main Cab Unit - Filter Illustration 6 g06296539The main cab unit air filter is located in the front lower third of the large unit. The area in front of this unit should remain open to ensure proper airflow. This filter should be checked weekly and replaced in every six months. (Cardboard shown in Illustration 6 should be removed before use).Second Unit Illustration 7 g06296540The second unit is located below the operator seat and provides airflow to the front left and right pillars. This airflow can be directed at the operator or at the front window depending on operating case.Second Unit - Vents Illustration 8 g06296541This unit has two large circular vents facing the operator and six additional vents facing the front and side windows. Each vent can be fully closed allowing airflow to be directed to the desired location. During defrost the circular vents facing the operator should be closed for best performance.Second Unit - Filters Illustration 9 g06296544 Illustration 10 g06296547This unit receives 50% of its airflow from recirculated cab air and the other 50% as fresh air. The recirculated air vent is located beneath the operator seat as shown in Illustration 9. To ensure the best airflow this area should be kept clear and check weekly. The fresh air intake is located on the boom side of the riser and is accessible from the ground. Refer to Illustration 10. This filter should be checked weekly and replaced in every six months.
