PREVOST X3-45 COMMUTER User Manual

SECTION 22: HEATING AND AIR CONDITIONING
22
DOB 1300-1556 | X3-45 Commuter PA-1648 Maintenance Manual First release Oct 2020
FIGURE 28 RECEIVER TANK X SERIES
In case of extreme pressure there will be a rise
in the liquid receiver tank. A pressure relief
valve will break at 450 psi and relieve the
receiver tank pressure.
The receiver tank incorporates an inlet valve on
the inlet side (upper section) which allows the
tank to be isolated or serviced. An outlet valve
on the outlet side (lower section) permits
complete isolation from the rest of the system.
During normal operation, inlet and outlet
shutoff valves are in back seated position (stem
out).
When connecting a gage to the service port,
make sure the shut-off valve is in back seated
position because the service port is not fitted
with a Schrader valve.
4.5 FILTER DRYER
A filter dryer, also located in the condenser
compartment, is installed on the liquid refrigerant
line after the receiver tank. It is used to absorb
moisture and foreign matter from refrigerant
before it reaches the expansion valves.
The filter dryer should be replaced after a
severe system failure, after a prolonged
exposure and most important, when the
moisture indicator sight glass turns to pink.
4.5.1 Replacement of the Filter-Dryer After
Pumping Down
The filter dryer is of the disposable type. When
replacement is required, remove and discard the
complete unit and replace with a new unit of the
same type according to this procedure:
1. Perform the pumping down procedure to
isolate refrigerant in the receiver tank.
2. Disconnect C24 to isolate the section of the
system located between the receiver tank
outlet shutoff valve and the passengers unit
liquid solenoid valve.
3. Change the filter dryer.
FIGURE 29: ISOLATED SECTION X SERIES
4. Once the filter dryer has been replaced, it is
necessary to evacuate the opened section
of the refrigerant circuit. Evacuate the
isolated section of the system using a
vacuum pump connected to the service port
of the receiver outlet shutoff valve.
5. Evacuate the section of the refrigerant
piping as needed and in accordance with
best practices, using a micron gage to
monitor the depth of vacuum. Evacuate to a
system pressure less than 1000 microns.
6. Turn off the vacuum pump.
7. Backseat the outlet shutoff valve and then
disconnect the vacuum pump hose.
CAUTION
Do not use carbon tetrachloride or similar
solvents to clean parts. Do not
use steam
guns
. Use mineral spirits or naphtha. All
parts should be thoroughly cleaned. Use a
stiff brush to wash dirt from grooves, holes,
etc.
DANGER
Cleaning products are flammable and may
explode under certain conditions. Always
handle in a well-ventilated area.

PREVOST X3-45 COMMUTER Specifications

General

Engine	Volvo D13
Transmission	Allison B500
Fuel Type	Diesel
Length	45 ft (13.7 m)
Width	102 in (2.6 m)
Horsepower	500 hp
GVWR	54, 000 lbs
Height	141 in