Carrier 38AU Install Filter Driers and Moisture Indicators, Refrigerant Specialties Part Numbers

CKT

2

CKT

1

CKT

2

CKT

1

Circuit 2

Connections

Circuit 1

Connections

C10355

Fig. 6 - 38AUD Service Valve Locations

Plan the Circuit 1 and Circuit 2 tubing segments carefully, mark each segment and check constantly as piping systems are assembled to avoid piping errors.

38AUD unit cannot be field-piped as a single-circuit/tandem system.

Connecting 40RU to 38AUD: The 40RU fan coil in sizes 16, 25 and 28 is a face-split coil design that also has its circuits designated as 1 and 2. See Fig. 7. Note that the lower coil segment changes as the arrangement of the 40RU changes. In a vertical arrangement, the 40RU’s lower coil segment is segment 2; this segment should be connected to the 38AUD’s Circuit 1. In a horizontal arrangement, the 40RU’s lower segment is now segment 1; this segment should be connected to the 38AUD’s Circuit 1.

Note that refrigerant suction piping should be insulated.

40RU	Cooling	40RU Coil	Connect to
Arrangement	Stage	Segment	38AUD
Vertical	Y1	2	Circuit 1
	Y2	1	Circuit 2
Horizontal	Y1	1	Circuit 1
	Y2	2	Circuit 2

Install Filter Drier(s) and Moisture Indicator(s) —

Every unit MUST have a filter drier in the liquid line. 38AUD models require two filter driers (one in each liquid line). Locate the filter drier(s) at the indoor unit, close to the evaporator coil’s thermal expansion valve (TXV) inlets.

38AU units include one (38AUZ) or two (38AUD) Puron-duty filter drier(s), shipped in cartons attached to the unit basepan. Remove the filter drier(s) and prepare to install in the liquid line(s) at the evaporator coil. Do not remove connection fitting plugs until ready to connect and braze the filter drier into the liquid line position.

1

2

FIRST ON/LAST OFF = 2

VERTICAL INSTALLATION

2

1

FIRST ON/LAST OFF = 1

HORIZONTAL INSTALLATION

C10071

Fig. 7 - Typical Evaporator Coil Connections (40RU)

Table 8 –		Puron-duty Filter Drier(s)
Model-Size	Qty	Liquid	Desiccant	Part
		Line OD	Volume	Number Ref
38AUZ*16	1	5/8-in	30 cu. in.	KH43LG087
38AUZ*25	1	5/8-in	30 cu. in.	KH43LG087
38AUD*16	2	1/2-in	16 cu. in.	KH43LG085
38AUD*25	2	1/2-in	16 cu. in.	KH43LG085

Installation of liquid line moisture indicating sightglass in each circuit is recommended. Locate the sightglass(es) between the outlet of the filter drier and the TXV inlet.

Refer to Table 9 for recommendations on refrigeration specialties.

38AU

Table 9 – Refrigerant Specialties Part Numbers.

LIQUID LINE		LIQUID LINE	LLSV	SIGHT	FILTER
SIZE (in.)		SOLENOID VALVE (LLSV)	COIL	GLASS	DRIER
1/	2	EF680035	EF680037	KM680004	provided with unit
5/8		EF680036	EF680037	KM680005	see Table 8

38AUD units require TWO sets of parts.

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