Bryant 538J-18-1 manual B. Subcooling Method Cooling, TXV, A - Superheat Charging Table - English

10.If air temperature entering outdoor coil or pressure at suction valve changes, charge to new suction line temperature indicated on chart.

NOTE: The above procedure is independent of indoor air quantity.

B. Subcooling Method (Cooling, TXV)

To check and adjust charge during cooling season, use Tables 6A and 6B and the following procedure:

1.Operate unit a minimum of 15 minutes before check- ing charge.

2.Measure liquid line temperature near liquid line ser- vice valve, and measure liquid pressure at liquid line service valve. Use a digital thermometer for all tem- perature measurements. DO NOT use mercury or dial-type thermometers.

3.Refer to Tables 6A and 6B. Find temperature point at which the required subcooling temperature intersects the measured liquid line pressure.

4.If the measured liquid line temperature does not agree with the required liquid line temperature, ADD refrigerant to lower the temperature, or REMOVE refrigerant to raise the temperature (allow a toler- ance of ± 3 F).

Table 4A — Superheat Charging Table — English

(Superheat Entering Suction Service Valve)

OUTDOOR			INDOOR COIL ENTERING AIR (F) WB
TEMP (F)	50	52	54	56	58	60	62	64	66	68	70	72	74	76
55	9	12	14	17	20	23	26	29	32	35	37	40	42	45
60	7	10	12	15	18	21	24	27	30	33	35	38	40	43
65	*	6	10	13	16	19	21	24	27	30	33	36	38	41
70	*	*	7	10	13	16	19	21	24	27	30	33	36	39
75	*	*	*	6	9	12	15	18	21	24	28	31	34	37
80	*	*	*	*	5	8	12	15	18	21	25	28	31	35
85	*	*	*	*	*	*	8	11	15	19	22	26	30	33
90	*	*	*	*	*	*	5	9	13	16	20	24	27	31
95	*	*	*	*	*	*	*	6	10	14	18	22	25	29
100	*	*	*	*	*	*	*	*	8	12	15	20	23	27
105	*	*	*	*	*	*	*	*	5	9	13	17	22	26
110	*	*	*	*	*	*	*	*	*	6	11	15	20	25
115	*	*	*	*	*	*	*	*	*	*	8	14	18	23

LEGEND

WB — Wet Bulb

*Do not attempt to charge system under these conditions or refrigerant slug- ging may occur.

Table 4B — Superheat Charging Table — SI (Superheat Entering Suction Service Valve)

OUTDOOR			INDOOR COIL ENTERING AIR (C) WB
TEMP (C)	10	11	12	13	14	16	17	18	19	20	21	22	23	24
13	5	7	8	9	11	13	14	16	18	19	21	22	23	25
16	4	6	7	8	10	12	13	15	17	18	19	21	22	24
18	*	3	6	7	9	11	12	13	15	17	18	20	21	23
21	*	*	4	6	7	9	11	12	13	15	17	18	20	22
24	*	*	*	3	5	7	8	10	12	13	16	17	19	21
27	*	*	*	*	3	4	7	8	10	12	14	16	17	19
29	*	*	*	*	*	*	4	6	8	11	12	14	17	18
32	*	*	*	*	*	*	3	5	7	9	11	13	15	17
35	*	*	*	*	*	*	*	3	6	8	10	12	14	16
38	*	*	*	*	*	*	*	*	4	7	8	11	13	15
41	*	*	*	*	*	*	*	*	3	5	7	9	12	14
43	*	*	*	*	*	*	*	*	*	3	6	8	11	14
46	*	*	*	*	*	*	*	*	*	*	4	8	10	13

LEGEND

WB — Wet Bulb

*Do not attempt to charge system under these conditions or refrigerant slug- ging may occur.

Table 5A — Required Suction-Tube Temperature (F)

— English (Entering Suction Service Valve)

SUPERHEAT	SUCTION PRESSURE AT SERVICE PORT (psig)
TEMP (F)	61.5	64.2	67.1	70.0	73.0	76.0	79.2	82.4	85.7
0	35	36	39	41	43	45	47	49	51
2	37	39	41	43	45	47	49	51	53
4	39	41	43	45	47	49	51	53	55
6	41	43	45	47	49	51	53	55	57
8	43	45	47	49	51	53	55	57	59
10	45	47	49	51	53	55	57	59	61
12	47	49	51	53	55	57	59	61	63
14	49	51	53	55	57	59	61	63	65
16	51	53	55	57	59	61	63	65	67
18	53	55	57	59	61	63	65	67	69
20	55	57	59	61	63	65	67	69	71
22	57	59	61	63	65	67	69	71	73
24	59	61	63	65	67	69	71	73	75
26	61	63	65	67	69	71	73	75	77
28	63	65	67	69	71	73	75	77	79
30	65	67	69	71	73	75	77	79	81
32	67	69	71	73	75	77	79	81	83
34	69	71	73	75	77	79	81	83	85
36	71	73	75	77	79	81	83	85	87
38	73	75	77	79	81	83	85	87	89
40	75	77	79	81	83	85	87	89	91

Table 5B — Required Suction-Tube Temperature (C)

— SI (Entering Suction Service Valve)

SUPERHEAT	SUCTION PRESSURE AT SERVICE PORT (kPa)
TEMP (C)	424	443	463	483	503	524	546	568	591
0	2	3	4	5	6	7	8	9	11
1	3	4	5	6	7	8	9	11	12
2	4	5	6	7	8	9	11	12	13
3	5	6	7	8	9	11	12	13	14
4	6	7	8	9	11	12	13	14	15
6	7	8	9	11	12	13	14	15	16
7	8	9	11	12	13	14	15	16	17
8	9	11	12	13	14	15	16	17	18
9	11	12	13	14	15	16	17	18	19
10	12	13	14	15	16	17	18	19	21
11	13	14	15	16	17	18	19	21	22
12	14	15	16	17	18	19	21	22	23
13	15	16	17	18	19	21	22	23	24
14	16	17	18	19	21	22	23	24	25
16	17	18	19	21	22	23	24	25	26
17	18	19	21	22	23	24	25	26	27
18	19	21	22	23	24	26	26	27	28
19	21	22	23	24	25	26	27	28	29
20	22	23	24	25	26	27	28	29	31
21	23	24	25	26	27	28	29	31	32
22	24	25	26	27	28	29	31	32	33

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