Heating & Air Conditioning
433
DRIVER’S HEATER AND DEFROSTER SySTEM
The driver’s heater and defroster system provides heated air to the driver’s area and heated air for the de-
froster system. The heat is supplied by engine coolant that is pumped from the engine by a booster pump
and the flow is controlled by the hot water control valve. The same pump also provides heated coolant to
the passenger air conditioner/heater. The air supply is filtered by a filter located in the front panel.
Maintenance
Maintenance of the Heater/Defroster System includes checking the hoses for leaks, flushing the coils to
clean away accumulated debris, and occasionally purging air from the hoses. Trapped air causes dimin-
ished coolant circulation and can be purged by slipping the hose off of the connector to let air escape.
When coolant runs from the hose, the air has been purged and the hose can be reconnected to the system.
Air Filter
The air filter element should be routinely inspected and cleaned or replaced as necessary to prevent dirt
accumulation from restricting air flow into the heater/defroster. Replace the filter element as follows:
1. Remove the filter retainer from the side slides.
2. Remove and clean or replace the filter element.
3. Reinstall the retainer into the slides to secure the filter element.
Hose Service
The hoses must be regularly inspected for chafing, wear, clamp tightness, or other signs of failure or
potential failure. Damaged or worn hoses or clamps should be replaced with new components.
BOOSTER PUMP
Your coach is equipped with a booster pump, mounted on a bracket next to the transmission on the
driver’s side of the coach, which delivers heated coolant to the driver’s heater, defroster, and optional
passenger heaters. The coolant flow is regulated by the hot water control valve. The coolant is carried to
the heater and back in hoses running the length of the coach in the left side of the frame.
The booster pump also provides engine coolant to the passenger heater/AC and to the optional auxiliary
coolant heater.
The booster pump is powered by an AMETEK brushless motor. This brushless or ECDC (electroni
-
cally commutated DC) motor requires less maintenance than a traditional copper commutator motor.
Power transistors replace the traditional copper commutator and carbon brushes, so there are no wearing
components except for bearings. Bearings will last longer because there is no brush dust to contaminate
them.
Summary of Contents for LOW FLOOR
Page 18: ...Specifications 18...
Page 58: ...Preventive Maintenance 58...
Page 110: ...Engine 110...
Page 138: ...Transmission Driveline Rear Axle 138...
Page 182: ...Suspension 182...
Page 260: ...Air System 260...
Page 420: ...Electrical System 420 Deutsch DT Series Connectors...
Page 421: ...Electrical System 421...
Page 422: ...Electrical System 422 Deutsch HD 10 Series Connectors...
Page 423: ...Electrical System 423...
Page 424: ...Electrical System 424 Deutsch HD 30 Series Connectors...
Page 425: ...Electrical System 425...
Page 442: ...Heating Air Conditioning 442...
Page 492: ...Body and Interior 492 Figure 11 33 USSC Seat Assembly...
Page 493: ...Body and Interior 493 Figure 11 34 USSC Seat Suspension Assembly...
Page 495: ...Body and Interior 495 Figure 11 37 Seat Air Connections...