Bryant 575A Iii. Complete Refrigerant Piping Connections, Ð Refrigerant Piping Sizes

Models: 575A

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III. COMPLETE REFRIGERANT PIPING CONNECTIONS

Suction connection is sweat with plastic cap; liquid connec- tion is sweat with plastic cap. Refer to Table 2 for the proper line sizes. Follow standard piping practices.

Table 2 Ð Refrigerant Piping Sizes

 

 

LINEAR LENGTH OF PIPING Ð ft

 

 

UNIT

0-25

 

25-50

50-75

75-100

 

 

 

Line Size (in. OD)

 

 

575A

 

 

 

 

 

 

L

S

L

 

S

L

S

L

S

090

1¤2

11¤8

5¤8

 

11¤8

5¤8

13¤8

3¤4

13¤8

 

 

 

LEGEND

 

 

 

 

L Ð Liquid Line

OD Ð Outside Diameter

S Ð Suction Line

NOTES:

1.Pipe sizes are based on a 2° F loss for liquid and suction lines.

2.Pipe sizes are based on the maximum linear length shown for each column, plus a 50% allowance for ®ttings.

3.Charge units with R-22 in accordance with unit installation instructions.

A. Size Refrigerant Lines

Consider length of piping required between 575A unit and 524A-H unit, amount of liquid lift, and compressor oil re- turn. See Table 3. Refer to 524A installation instructions for additional information.

Table 3 Ð Liquid Line Data

UNIT

MAX

 

 

ALLOWABLE

LIQUID LINE

575A

LIQUID LIFT (ft)

 

 

 

 

 

 

 

 

Max Allowable

Max Allowable

090

Heating

Cooling

Pressure Drop

Temp Loss

 

 

(psi)

(F)

 

 

 

 

75

65

7

2

LEGEND

db Ð Dry Bulb wb Ð Wet Bulb

NOTES:

1.The liquid lift in cooling mode is based on 80/67 F (db/wb ) entering indoor-air temperature and a 95 F outdoor-air temperature, with R-22 refrigerant, at an indoor air¯ow of 3000 cfm.

2.The liquid lift in heating mode is based on 70/60 F (db/wb) entering indoor-air temperature and a 47/43 F (db/wb) outdoor-air tempera- ture, with R-22 refrigerant, at an indoor air¯ow of 3000 cfm.

B. Filter Drier and Moisture Indicator

See Fig. 5. The ®lter drier is factory supplied and ®eld- installed in the liquid line. Moisture indicator is ®eld- supplied and should be installed just after liquid line shutoff valve. Do not use a receiver; there is none provided with unit and one should not be used.

NOTE: Unit is shipped with R-22 holding charge. System pres- sure must be relieved before removing caps. Recover refrig- erant prior to brazing.

Pass nitrogen or other inert gas through piping while braz- ing to prevent formation of copper oxide.

C. Liquid Line Solenoid Valve

A ®eld-supplied liquid line solenoid valve (LLSV) is recom- mended when piping system length exceeds 75 feet. The LLSV must be of the bi¯ow type, suited for use in heat pump systems.

NOTE: Part number EF23JS214 (Sporlan model CB14S2, 5¤8-in. ODF/7¤8-in. ODM) is recommended and is available from the Replacement Components Division. This solenoid re- quires ®eld-supplied Sporlan MKC-2 coils.

Wire the solenoid in parallel with the compressor contactor coil.

Install the LLSV near the outdoor unit. The ¯ow arrow must be pointed toward the outdoor unit.

D. Safety Relief

A fusible plug is located on top of the accumulator. See Fig. 6. Note that all safety relief components are factory installed. Do not cap fusible plug. If local code requires additional safety device(s), install as directed.

E.Suction Piping at Indoor Coil and TXV Sensing Bulb Location

Suction piping must be designed so that refrigerant is thor- oughly mixed after it leaves the indoor coil suction header. The thermostatic expansion valve (TXV) sensing bulb must also be correctly located. This ensures that the TXV sensing bulb receives reliable readings. Install the suction piping as follows:

1.Install a minimum of two 90-degree elbows upstream of the TXV bulb location.

2.Locate the TXV bulb on a vertical riser where possible. If a horizontal location is necessary, secure the bulb at approximately the 4 o'clock position or the 8 o'clock po- sition. See Fig. 7.

3.Make sure that the piping system has no inherent oil traps, and that the piping layout does not allow oil to migrate into an idle indoor coil.

4.Complete refrigerant piping from indoor coil to outdoor coil before opening liquid and suction lines at the 575A unit. See Tables 1 and 2 for piping selection data.

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Bryant 575A Iii. Complete Refrigerant Piping Connections, Ð Refrigerant Piping Sizes, A. Size Refrigerant Lines