Carrier 38AH044-084 specifications Ð Install Accessories, Pre-Start-Up, System Check

Table 15 Ð Main Power Connection and Control Circuit Wiring

	MAIN POWER CONNECTION			CONTROL CIRCUIT
Electrical	Qty	Qty	Max Wire	Control Power	Safety Circuit
Characteristics	Terminal	Parallel	Size
				(V)	(V)
(V-Ph-Hz)	Blocks	Conductors*	(kcmil)
208/230-3-60	1	6	500	115²	24
460-3-60	1	3	500	115²	24
575-3-60
230-3-50	1	6	500	230	24
380-3-60	1	3	500	230	24
380/415-3-50
346-3-50	1	3	500	200	24

LEGEND

kcmil Ð Thousand Circular Mils

*Conductors are from the safety disconnect.

²Control power is accomplished with a step-down transformer where primary voltage is ®eld voltage.

Step 5 Ð Install Accessories

LOW-AMBIENT OPERATION

Units 38AH044-084, 124, and 134 Ð If operating tempera- tures below 55 F (13 C) are expected, Motormaster III fan motor control is recommended. Refer to separate installa- tion instructions for low-ambient operation guidelines.

Units 38AH094 and 104 Ð If operating temperatures below 45 F (7 C) are expected, Motormaster III fan motor control is recommended. Refer to separate installation instructions for low-ambient operation guidelines.

MISCELLANEOUS ACCESSORIES Ð For applications requiring special accessories, the following packages are available: condenser coil hail guard package, gage panel, unloader package, unloader conversion kits, sound reduc- tion package, condenser coil protective grilles, compressor security grilles, ModuPanel™ control, and thermostat trans- former relay package.

PRE-START-UP

IMPORTANT: Before beginning Pre-Start-Up or Start- Up, review Start-Up Checklist at the back of this pub- lication. The Checklist assures proper start-up of a unit and provides a record of unit condition, application re- quirements, system information, and operation at ini- tial start-up.

Do not attempt to start the air-conditioning system until following checks have been completed.

System Check

1.Check all system components, including the air- handling equipment. Consult manufacturer's instruc- tions. If the unit has ®eld-installed accessories, be sure all are properly installed and wired correctly. Refer to unit wiring diagrams.

2.Backseat (open) compressor suction and discharge shut- off valves. Close valves one turn to allow refrigerant pres- sure to reach the test gages.

3.Open liquid line service valves.

4.Check tightness of all electrical connections.

5.Oil should be visible in the compressor sight glasses. See Fig. 29. An acceptable oil level in the compressor is from 1¤8 to 1¤3 of sight glass. Adjust the oil level as required. No oil should be removed unless the crank- case heater has been energized for at least 24 hours. See Preliminary Oil Charge section on page 38, for Carrier- approved oils.

6.Electrical power source must agree with unit nameplate.

Crankcase heaters on all units are wired into the control circuit, so they are always operable as long as the main power supply disconnect is on (closed), even if any safety device is open. Compressor heat- ers must be on for 24 hours prior to the start-up of any compressor.

7.Crankcase heaters must be ®rmly locked into compres- sors, and must be on for 24 hours prior to start-up.

8.Fan motors are 3-phase. Check rotation of fans during ®rst start-up check. Fan rotation is clockwise as viewed from top of unit. If fan is not turning clockwise, reverse 2 of the power wires.

9.Check compressor suspension. On units 38AH044-084, 124, and 134, snubber washers (for noise suppression) can be moved with ®nger pressure. On units 38AH094 and 104, rails allow compressors to ¯oat freely on com- pressor rail springs.

10.On 38AH074,084 single-circuit units and Module 38AH134B, ensure that the packaging block located be- tween the oil equalization tube and the compressor cross- brace has been removed.

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