02 2021 Allegro Breeze PowerGlide Brake System
Brake System
• Front brakes are air applied disc
• Rear brakes (Figure 2-1) double as parking brake
- Park brakes are spring applied
- Two large 15 x 8.625” drum brakes
- Park brake remains applied even if air pressure is lost
• If air pressure is lost
- A buzzer and warning lamp will alert you
• Chassis is equipped with automatic slack adjusters (Figure 2-2)
- No brake adjustment required
The rear brakes on the PowerGlide chassis are also used as the parking brakes. This provides you the holding power of two large drum brakes to prevent your coach from rolling, even when fully loaded on a 20% grade.
A decrease in air pressure will not cause an immediate loss of brakes. If a leak develops in the air system while driving, at approximately 60 to 65 PSI you will be alerted via a light on the instrument panel, and an audible alarm will sound. As you apply the brakes, the air supply holding the park brakes in the released position will gradually be depleted. When fully depleted, approximately 40 PSI to 45 PSI, the rear brakes will set. This allows you sufficient time to pull over to the side of the road.
NOTE: The rear brakes have dual chambers – one for the service brakes and one for the park brake. The service brakes are air applied and spring released. The park brake is spring applied and air released.
The brake system is equipped with automatic slack adjusters that avoid the need to manually adjust your brakes. Each time you step on the brake pedal, if adjustment is needed, the adjusters will take up the slack.
Compressed Air System
Tank Drains
The compressed air system is comprised of multi-air storage tanks. The primary tank stores and supplies air for the rear brakes, the secondary tank stores and supplies air for the front brakes.
When air is compressed it becomes hot. As it cools, condensed moisture forms in the system. The air system is equipped with an air dryer to remove most of this moisture. The dryer has an automatic moisture ejector that releases the trapped moisture back into the atmosphere. However, some moisture will form in the system beyond the dryer, and make its way into the storage tanks. As moisture collects in the primary and secondary tanks, it displaces the area needed for air storage, thus requiring that the tanks be drained periodically.
The air system is equipped with air tank drains conveniently located in the left rear storage compartment (Figure 2-3). There is one drain for the primary tank and one for the secondary tank. These drains should be opened daily for a few seconds to remove any moisture trapped in the tanks.
Air Dryer
The Tiffin PowerGlide chassis air brake system features a Parker air dryer (Figure 2-4), which removes the condensed moisture from compressed air. The air dryer is equipped with a desiccant cartridge that needs to be changed every 36 months. The dryer is located on the driver’s side behind the compartment that holds the a/c condenser and air tanks.
