Carrier 38AKS013-024 specifications Location of Sight Glasses Filter Driers

INSTALL FILTER DRIER(S) AND MOISTURE INDICA- TOR(S) Ð Every unit should have a ®lter drier and liquid- moisture indicator (sight glass). In some applications, depending on space and convenience requirements, it may be desirable to install 2 ®lter driers and sight glasses. One ®lter drier and sight glass may be installed at A locations in Fig. 5. Or, 2 ®lter driers and sight glasses may be installed at B locations.

Select the ®lter drier for maximum unit capacity and mini- mum pressure drop. Complete the refrigerant piping from indoor unit to outdoor unit before opening the liquid and suc- tion lines at the outdoor unit.

TXV Ð Thermostatic Expansion Valve

Fig. 5 Ð Location of Sight Glass(es)

and Filter Drier(s)

INSTALL LIQUID LINE SOLENOID VALVE Ð SOLE- NOID DROP Ð It is recommended that a solenoid valve be placed in the main liquid line (see Fig. 5) between condens- ing unit (38AKS) and fan coil (40RM, 39 Series). (A liquid line solenoid valve is required when the liquid line length exceeds 100 ft [30.5 m] or when the condensing unit is con- nected to a chiller barrel in a built-up chiller system.) This valve prevents refrigerant migration (which causes oil dilu- tion) to the compressor during the off cycle at low outdoor ambient temperatures. The solenoid should be wired in par- allel with the compressor contactor coil. This means of elec- trical control is referred to as solenoid drop control.

INSTALL LIQUID LINE SOLENOID VALVE (Optional)

ÐCAPACITY CONTROL Ð If 2-step cooling is desired, place a solenoid valve in the location shown in Fig. 5.

MAKE PIPING CONNECTIONS Ð Do not remove run- around loop from suction and liquid line stubs in the com- pressor compartment until piping connections are ready to be made. Pass nitrogen or other inert gas through piping while brazing to prevent formation of copper oxide.

Recover holding charge prior to removal of runaround piping loop.

1.Open service valves:

a.Discharge service valve on compressor.

b.Suction service valve on compressor.

c.Liquid line valve.

2.Remove 1¤4-in. ¯are cap from liquid valve Schrader port.

3.Attach refrigerant recovery device and recover holding charge.

4.Remove runaround loop.

5.Install a ®eld-supplied liquid moisture indicator in the pip- ing immediately leaving outdoor unit.

6.If necessary, install ®eld-supplied thermostatic expan- sion valve(s) (TXVs) in air handler.

If 2 TXVs are installed and two-step cooling is desired, install ®eld-supplied liquid line solenoid valve ahead of the upper TXV (see Fig. 5).

PROVIDE SAFETY RELIEF Ð A fusible plug is located on the compressor crankcase or in the liquid line (Fig. 6). Do not cap this plug. If local code requires additional safety devices, install them as directed.

NOTE: 38AKS024 has a fusible plug in the liquid line.

Fig. 6 Ð Location of Fusible Plug (38AKS)

Step 4 Ð Install Accessories Ð Field install accessories such as winter start control or low-ambient con- trol before proceeding with wiring. Refer to the instructions shipped with the accessory.

Step 5 Ð Complete Electrical Connections

POWER WIRING Ð Unit is factory wired for voltage shown on nameplate. Provide adequate fused disconnect switch within sight from unit and readily accessible from unit, but out of the reach of children. Lock switch open (off) to prevent power from being turned on while unit is being serviced. Dis- connect switch, fuses, and ®eld wiring must comply with national and local code requirements. See Tables 6A and 6B.

Route power wires through opening in unit end panel to connection in unit control box as shown on unit label dia- gram and in Fig. 7. Unit must be grounded.

Affix crankcase heater warning sticker to unit disconnect switch.

CONTROL CIRCUIT WIRING Ð Control voltage is 24 v. See Fig. 8 and unit label diagram for ®eld-supplied wiring details. Route control wires through opening in unit end panel to connection in unit control box.

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