Bryant 591B Required LIQUID-LINE Temperature F, Cooling only Procedure, Units with Indoor Pistons

TABLE 3—REQUIRED LIQUID-LINE TEMPERATURE (°F)

LIQUID			REQUIRED SUBCOOLING
PRESSURE AT			TEMPERATURE
SERVICE VALVE				(°F)
(PSIG)	8	10	12		14	16	18
189	58	56	54		52	50	48
195	60	58	56		54	52	50
202	62	60	58		56	54	52
208	64	62	60		58	56	54
215	66	64	62		60	58	56
222	68	66	64		62	60	58
229	70	68	66		64	62	60
236	72	70	68		66	64	62
243	74	72	70		68	66	64
251	76	74	72		70	68	66
259	78	76	74		72	70	68
266	80	78	76		74	72	70
274	82	80	78		76	74	72
283	84	82	80		78	76	74
291	86	84	82		80	78	76
299	88	86	84		82	80	78
308	90	88	86		84	82	80
317	92	90	88		86	84	82
326	94	92	90		88	86	84
335	96	94	92		90	88	86
345	98	96	94		92	90	88
354	100	98	96		94	92	90
364	102	100	98		96	94	92
374	104	102	100		98	96	94
384	106	104	102		100	98	96
395	108	106	104		102	100	98
406	110	108	106		104	102	100
416	112	110	108		106	104	102
427	114	112	110		108	106	104
439	116	114	112		110	108	106
450	118	116	114		112	110	108
462	120	118	116		114	112	110
474	122	120	118		116	114	112
486	124	122	120		118	116	114
499	126	124	122		120	118	116
511	128	126	124		122	120	118

EXAMPLE:

To calculate additional charge requried for a 25-ft line set:

25 ft - 15 ft = 10 ft X 0.6 oz/ft = 6 oz of additional charge.

B. COOLING ONLY PROCEDURE

UNITS WITH COOLING MODE PURON® TXV

Units installed with cooling mode TXV require charging by the subcooling method.

1.Operate unit a minimum of 10 minutes before checking charge.

2.Measure liquid service valve pressure by attaching an accurate gage to service port.

3.Measure liquid line temperature by attaching an accurate thermistor type or electronic thermometer to liquid line near outdoor coil.

4.Refer to unit rating plate for required subcooling tempera- ture.

5.Refer to Table 3. Find the point where required subcooling temperature intersects measured liquid service valve pres- sure.

—7—

6.To obtain required subcooling temperature at a specific liquid line pressure, add refrigerant if liquid line tempera- ture is higher than indicated or reclaim refrigerant if temperature is lower. Allow a tolerance of ± 3°F.

UNITS WITH INDOOR PISTONS

Units installed with indoor pistons require charging by the super- heat method.

The following procedure is valid when indoor airflow is within ± 21 percent of its rated CFM.

1.Operate unit a minimum of 10 minutes before checking charge.

2.Measure suction pressure by attaching an accurate gage to suction valve service port.

3.Measure suction temperature by attaching an accurate thermistor type or electronic thermometer to suction line at service valve.

4.Measure outdoor air dry-bulb temperature with thermom- eter.

5.Measure indoor air (entering indoor coil) wet-bulb tempera- ture with a sling psychrometer.