Fedders CH18ABD1 warranty Connect Refrigerant Piping, Precautions, 118, Liquid Line Sizes

CONNECT REFRIGERANT PIPING

The following should be followed when installing refrigerant piping. Comply with all local, state, and federal codes and/or regulations pertaining to this type of equipment and its installation.

1.Run the tubing by the most direct route and support every few feet. Do not run the lines underground unless they are in a chase. Leave enough material between structure and unit to absorb vibration.

2.Insulate the vapor line to prevent sweating and line loss. In underground chases, the vapor line should be insulated to provide vibration isolation between the vapor and liquid line. A minimum of 3/8” insulation is recommended in conditioned space and 1/2” to 3/4” in unconditioned space. Ensure that tubing insulation is pliable and completely surrounds vapor tube.

3.In general, the piping should be sloped toward the outdoor unit to prevent oil trapping. Where vertical risers occur, a suction line trap should be located at the base of the riser to assure proper oil return.

WARNING

REFRIGERANT LINE LENGTH MUST NOT EXCEED 75’ ON HORIZONTAL RUNS AND 40’ ON VERTICAL RISERS.

Precautions

Refer to the chart below for the minimum recommended tube outside diameter sizes on liquid and suction lines. Ensure that vapor and liquid tube diameters are appropriate for unit capacity. Run refrigerant tubes as directly as possible by avoiding unnecessary turns and bends.

•Undersized line sets will increase the refrigerant pressure drop between the indoor evaporator and outdoor unit, resulting in a decrease in system capacity. Oversizing the line sets may result in excessive refrigerant charge, thereby making the system more susceptible to liquid migration.

•When passing refrigerant tubes through the wall, seal opening with RTV or other pliable silicon based caulk

•Avoid direct tubing contact with water pipes, duct work, floor joists, wall studs, floors, and walls

•Do not suspend refrigerant tubing from joists and studs with a rigid wire or strap which comes in direct contact with tubing

•When necessary, use hanger straps which are 1 in. wide and conform to shape of tubing insulation

•Isolate hanger straps from insulation by using metal sleeves bent to conform to shape of insulation

•Condensing units are available with pre-charged, sweat-type copper connecting fittings

Units are factory charged for 15’ of line set tubing.

			•
118		OUTDOOR
			•
LIQUID		SECTION
LINE			•
	20’	Can only be
		20’ vertical
INDOOR		separation
COIL		without
		additional
SUCTION		accessories.
LINE
WARNING

IF THE INSTALLER IS MAKING UP HIS OWN LINE SETS, HE MUST MAKE SURE THE TUBING IS CLEAN OF ANY IMPURITIES OR MOISTURE. USE ONLY CLEAN AIR CONDITIONING AND REFRIGERATION GRADE SEAMLESS COPPER TUBING. PLUMBING GRADE COPPER IS INADEQUATE. TO ENSURE A CLEAN SYSTEM FREE OF ANY CONTAMINANTS, PURGING WITH DRY NITROGEN AND A DEEP VACUUM IS NECESSARY ON ALL SWEAT-TYPE MODELS AND ON THE UNCHARGED PORTIONS OF ALL MODELS NOT INCORPORATING PRECHARGED LINES. IT IS DESIRABLE TO PULL A VACUUM TO 1,000 MICRONS (29.96”

HG) TO ENSURE TROUBLE FREE OPERATION.

Adjust charge 0.66 oz per foot of variation from chart for 3/8” and 3/4” line set.

Adjust charge 0.67 oz per foot of variation from chart for 3/8" and 7/8" line set.

Adjust charge 0.72 oz per foot of variation from chart for 1/2" and 1 1/8" line set.

Liquid Line Sizes

HEAT PUMP		LINE SET LENGTH AND SIZE
MODEL	15 FT		25 FT	50 FT	75 FT
NUMBER
	LINE SET		LINE SET	LINE SET	LINE SET*
CH18ABD1	3/8”		3/8”	3/8”	3/8”
CH24ACD1	3/8”		3/8”	3/8”	3/8”
CH30ACD1	3/8”		3/8”	3/8”	3/8”
CH36ACD1	3/8”		3/8”	3/8”	3/8”
CH42ACD1	3/8”		3/8”	3/8”	3/8”
CH48ACD1	3/8”		3/8”	1/2”	1/2”

Suction Line Sizes

HEAT PUMP		LINE SET LENGTH AND SIZE
MODEL	15 FT		25 FT	50 FT	75 FT
NUMBER
	LINE SET		LINE SET	LINE SET	LINE SET*
CH18ABD1	3/4”		3/4”	3/4”	3/4”
CH24ACD1	3/4”		3/4”	3/4”	3/4”
CH30ACD1	7/8”		7/8”	7/8”	7/8”
CH36ACD1	7/8”		7/8”	7/8”	7/8”
CH42ACD1	7/8”		7/8”	7/8”	1 1/8”
CH48ACD1	7/8”		1 1/8”	1 1/8”	1 1/8”

* DO NOT EXCEED 75 FT MAXIMUM LINE SET LENGTH

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