PREVOST LE MIRAGE XLII BUS SHELLS, Руководство по обслуживанию

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Section 22: HEATING AND AIR CONDITIONING
PA1564
27
2. Unscrew the flange retaining screws on the
shaft end side (opposite to the commutator
end frame), and separate flange from frame
(Fig. 31).
3. Remove flange and armature assembly by
pushing bearing shaft toward the
commutator end frame.
4. Separate flange from armature.
9.4.4 Disassembly
1. Perform preliminary disassembly.
2. Carefully note the position of the brush
holder ring and the connections on the
flange support.
3. Unscrew and remove the flange on the
commutator end frame.
4. Remove the brush holder ring.
5. Finally, separate the following parts: brush
holders, brush boxes, terminal board,
bearings, etc.
9.5 RECEIVER TANK
The receiver tank is located in the condenser
compartment (Fig. 32). The function of the
receiver tank is to store the liquid refrigerant.
During normal operation, the level of the
refrigerant should be approximately at the mid-
point of the lower sight glass.
In case of extreme pressure there will be a rise
in the liquid receiver tank. A pressure relief valve
will break at 450 psi (3103 kPa) 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.
9.6 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 should be replaced if the system has
been opened or after a prolonged exposure,
when the moisture indicator sight glass turns to
pink.
FIGURE 32: A/C CONDENSER COMPARTMENT
22243B
9.6.1 Replacement
The filter 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. Isolate the refrigerant in the receiver tank by
following the “Pumping Down” procedure
explained in this section
2. Change the filter dryer as a unit.
3. Add a small quantity of refrigerant R-134a to
the low side of the system. Check for leaks.
Return the system to normal operation.
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.
9.6.2 Moisture Indicator
The moisture sensitive element consists of a
color changing ring which is reversible from pink
to blue and vice versa as the moisture content in
the refrigerant changes. Pink indicates a wet
refrigerant, light violet (caution) and blue
indicates a dry refrigerant.