Bryant 575C, 575B Pre-Start-Up, Preliminary Checks, → Recommended Process for Checking for Leaks

PRE-START-UP

IMPORTANT: Before beginning Pre-Start-Up or Start-Up, review Start-Up Checklist at the back of this book. The checklist assures proper start-up of the system and provides a record of unit condition, application requirements, system information, and operation at initial start-up.

CAUTION: Do not attempt to start the heat pump system, even momentarily, until the following steps have been completed. Compressor damage may result.

I.PRELIMINARY CHECKS

1.Check all air handler and other equipment auxiliary components. Consult manufacturer’s instructions re- garding any other equipment attached to unit. If unit has field-installed accessories, be sure all are properly installed and correctly wired. If used, airflow switch must be properly installed. See Fig. 14 for typical field wiring.

2.As shipped, compressor is held down by 4 bolts. After unit is installed, loosen each bolt and locknut until flat washer or snubber can be moved with finger pres- sure. Be sure compressor floats freely on the mount- ing springs (541A units only). See Fig. 15A and 15B for compressor mounting.

3.Check tightness of all electrical connections.

4.Electrical power source must agree with nameplate rating.

5.Turn on crankcase heater for 24 hours before starting the unit to be sure all refrigerant is out of the oil. To energize crankcase heater, perform the following steps:

a.Set the space thermostat system switch to OFF, or adjust the temperature so there is no demand for cooling.

b.Close the field disconnect.

c.Leave the compressor circuit breaker off. The crankcase heater is now energized.

6.Leak test the field refrigerant piping, connections and joints, and indoor coil. To perform leak test, com- plete the following steps:

a.Pressurize refrigerant piping; do not exceed 150 psi.

b.Using soap bubbles and/or an electronic leak detector, test refrigerant piping, connections and joints, and the indoor coil. See Fig. 16.

c.Check for leaks.

Evacuate and dehydrate entire refrigerant system.

7.541A180 only — compressor oil level should be visible in sight glass. Adjust the oil level as required. No oil should be removed unless the crankcase heater has been energized for at least 24 hours. See Start-Up section, Preliminary Oil Charge.

NOTE: The 575B, 575C units do not have a compres- sor oil level sight glass. These units are factory charged with the required amount of oil. If required, use the following oil for replacement: For 575B units use Zerol 150, part number P903-2001. For 575C units use RCD, part number P903-0101.

8.Backseat (open) compressor suction and discharge valves. Now close valves one turn to allow refrigerant pressure to reach test gages.

SNUBBER WASHER

SELF-LOCKING

BOLT

NEOPRENE

SNUBBER

COMPRESSOR FOOT

Fig. 15A — Compressor Mounting — 575B072 and

575C090,120 Units

Fig. 15B — Compressor Mounting — 541A180 Units

	150 PSI MAX
	DRY
	NITROGEN
		LIQUID LINE	INDOOR
	SUCTION LINE	SOLENOID VALVE	COIL
OUTDOOR
UNIT	LIQUID LINE	TXV

SOAP

→Fig. 16 — Recommended Process for Checking for Leaks

II.PRELIMINARY CHARGE

CAUTION: The 575C090 and 575C120 units contain a 9 lb charge of refrigerant. Add remainder of preliminary charge and allow pressure to equalize before starting compressor. Failure to do so WILL cause the compressor to overheat in a few minutes, possibly causing permanent compressor damage. The amount of refrigerant added must be at least 80% of the operating charge listed in the Physical Data table (Table 1).

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