Service - Bryant 541A Installation, Start-Up And Service Instructions Manual

Fig. 12 — Cooling Cycle Charging Chart,
Fig. 13 — Cooling Cycle Charging Chart,
541A180
E. Oil Charge (Table 1)
Allow unit to run for about 20 minutes. Stop unit and check
compressor oil level. Add oil only if necessary to bring oil into
view in sight glass. Refer to Preliminary Oil Charge section
on page 12. Use only approved compressor oil.
F. Check Operation
Ensure operation of all safety controls. Replace all service
panels. Be sure that control panel cover is closed tightly.
IX. RESTART
Manual reset of the 24-v control circuit is necessary if unit
shutdown is caused by automatic reset devices (including IP
[internal compressor overcurrent protection], HPS [high-
pressure switch], and LCS [loss-of-charge switch]) or if
541A120
shutdown is caused by manual reset devices (including OPS
[oil pressure switch] and compressor circuit breaker protec-
tion). To restart the unit when IP, HPS, or LCS has tripped
(after device has reset automatically), open and then close the
thermostat contacts. Opening and then closing thermostat
contacts interrupts and restores 24-v power to the compres-
sor lockout (CLO), which resets the circuit.
It is necessary to manually reset the compressor circuit
breaker and OPS at the unit if either of these safeties should
shut down the unit.
IMPORTANT: If OPS trips, it must be reset first before mak-
ing and breaking the thermostat contacts to reset CLO. If
this procedure is not followed, the CLO cannot reset.
X. CAUSES OF COMPLETE UNIT SHUTDOWN:
• interruption of supplied power
• open compressor overtemperature protection (IP)
• compressor electrical overload protection (CB)
• open high-pressure or loss-of-charge safety switches
• open oil pressure switch
• open crankcase heater lockout (CLO2)
• open control circuit fuse (FU1 or FU2)
I. COMPRESSOR REMOVAL
See Table 1 for compressor information and Fig. 2 for compo-
nent location. Follow safety codes and wear safety glasses
and work gloves.
1. Shut off power to unit. Remove unit access panel
(front of unit).
2. Recover refrigerant from system using refrigerant
recovery methods described in Training booklet
GTAC II, Module 5, and in accordance with local and
national standards.
3. Disconnect compressor wiring at compressor termi-
nal box.
4. Remove bolts from suction and discharge service
valves.
5. Remove 2 bolts and 2 screws from compressor mount-
ing plate.
CAUTION: Excessive movement of copper lines at
com-pressor may cause higher levels of vibration when
unit is restored to service.
6. Remove crankcase heater from compressor base.
7. Remove compressor from unit.
8. Remove compressor holddown bolts and lift compres-
sor off mounting plate.
9. Clean system. Add new liquid line filter drier.
10. Install new compressor on compressor mounting
plate and position in unit. Connect suction and dis-
charge lines to compressor. Secure mounting plate
with compressor to unit. Ensure that compressor
holddown bolts are in place. Connect wiring. Install
crankcase heater
11. Evacuate and recharge unit.
12. Restore unit power.
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SERVICE