PREVOST X3-45 COMMUTER User Manual

SECTION 22: HEATING AND AIR CONDITIONING
30
DOB 1300-1556 | X3-45 Commuter PA-1648 Maintenance Manual First release Oct 2020
4.11 HOT WATER CIRCULATING PUMP
This vehicle is provided with a brushless/sealess
water circulation pump which is in the
compartment located aft of the evaporator
compartment (Figure 40). The assembly
consists of a centrifugal pump and an electric
motor mounted in a compact assembly.
FIGURE 40: CIRCULATING PUMP LOCATION
The brushless DC sealess circulating pump
requires no periodic maintenance. The sealess
design offers leak-proof protection and the
capability to resist harsh environmental
conditions. The pump magnetically couples to
the brushless DC motor without a wet seal to
wear or replace, this coupling method also
enables easy motor removal without requiring
system draining. The pump electronically
commutated brushless DC motor provides
virtually maintenance-free operation over time
by eliminating brush maintenance and
associated brush motor failure.
Inspection of the circulating pump, to determine
if the pump is working properly, should be made
while the pump is in operation.
If there is evidence that the circulating pump is
not operating as per specifications, the unit must
be disassembled for repair.
Disassembly of the pump will be necessary only
in the case of a rotor failure or motor failure.
• Removal
1. Stop engine and allow engine coolant time
to cool.
2. Close shutoff valves. Refer to "05
COOLING" under heading "Draining
Cooling System" for location of valves.
3. Disconnect the electrical wiring from the
motor.
WARNING
Before proceeding with
the following steps,
check that coolant has cooled down.
4. Disconnect water lines from the pump at
flange connections. Place a container to
recover the residual coolant in the line.
5. Remove the two clamps holding the pump
motor to its mounting bracket. Remove the
pump with the motor as an assembly.
• Installation
1. Apply gasket cement to the line flanges, put
the two gaskets in place, and connect water
lines to the pump at the flange connections.
Position the pump and motor assembly on
the mounting bracket. Position the
mounting clamps over the motor and
secure with mounting bolts.
2. Connect electrical wiring to the pump motor.
3. Open shutoff valve. Refer to "05 COOLING"
under heading "Draining Cooling System"
for location of valves.
4. Fill the cooling system as previously
instructed in this section under "6.6.4 Filling
Heating System", then bleed the system as
previously instructed in this section under
"6.6.5 Bleeding Heating System".

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