Evaporator Removal; Evaporator Installation - Piper Dakota Maintenance Manual

EVAPORATOR

EVAPORATOR REMOVAL

The evaporator assembly consists of evaporator core, receiver-dehydrator, expansion valve, circulating fan,
pressure switch, housing, and associated plumbing. The housing is fabricated of thermoplastic. Condensed
moisture is dumped overboard through a hose clamped to a fitting on bottom of evaporator housing.
Evaporator assembly is located behind cabin rear panel. It is attached to the mounting panel with 12
screws and washers and a bracket securing back to mounting panel.
1. Remove air conditioning filter cover, filter, and rear access panels
Discharge system before disassembling any components for
service.
2. Uncouple liquid line from inlet side of receiver-dehydrator and suction line from evaporator core
outlet. (See Special Servicing Procedures.)
3. Disconnect related electrical wires.
4. Remove flexible air duct from housing outlet- Remove drain hose from housing.
5. Remove temperature probe from evaporator housing.
6. Remove screws attaching support bracket and evaporator housing to mounting panel- Remove
assembly through access hole in bulkhead.

EVAPORATOR INSTALLATION

l. Cement gasket in place on flanges of evaporator housing and attach large end of mounting gasket to
back of housing.
2. Install housing through access hole with air duct outlet on top. Mate mounting flanges to mating
surface of mounting panel and insert screws, do not tighten at this time.
3. Line up mounting bracket with mating holes in mounting panel, insert screws and tighten. Ti g h t e n
screws in flange. Be sure gasket is in place. Flange must have an air tight seal.
4. Couple suction and discharge lines to their respective fittings (apply Loctite refrigerant sealant to tube
flanges only).
5. Evacuate and charge system. (See Evacuating the System and Charging the System.)
6. Check for leaks (see Checking the System for Leaks). lf no leaks are detected, seal and install access
panel on evaporator housing.
7. Couple flexible air duct and drain tube.
8. Make and check electrical connections.
9. Check operation of blower and refrigerant systems.
Whenever it is necessary to remove rear cabin panel, replace ant
seal it in the original manner to prevent exhaust from entering
the cabin.
10. Install rear bulkhead panels, and seal.
11. Conduct a carbon monoxide test on ground and in flight with and without air conditioner operating,
CO may not exceed one part in 20,000.
PIPER AIRCRAFT
PA-28-236
MAINTENANCE MANUAL
—NOTE—
—WARNING—
1H2
21 - 57 - 00
Page - 21 - 36
Reissued: August 1, 1986