Trane 4TWB3 Subcooling Charging in Cooling Above 55F OD Ambient, 410A Refrigerant Charging Chart

Installer’s Guide

SUBCOOLING CHARGING IN COOLING ABOVE 55°F OD AMBIENT

The Trane company has always recommended installing Trane approved matched indoor and outdoor systems.

All Trane split systems are ARI rated with only TXV indoor systems.

The benefits of installing approved indoor and outdoor split systems are maximum efficiency, optimum performance and the best overall system reliability.

remove refrigerant to lower the pressure. Again, wait twenty (20) minutes for the system conditions to stabilize before adjusting charge again.

8.When system is correctly charged, you can refer to System Pressure Curves (in Service Facts) to verify typical performance.

The following charging methods are therefore prescribed for systems with indoor TXVs.

1.Subcooling (in the cooling mode) is the only recommended method of charging above 55°F ambient temperatures.

2.For best results - the indoor temperature should be kept between 70°F to 80°F. Add system heat if needed.

3.At start-up, or whenever charge is removed or added, the system must be operated for a minimum twenty (20) minutes to stabilize before accurate measurements can be made.

4.Measure Liquid Line Temperature and Refrigerant Pressure at service valves.

5.Determine total refrigerant line length, and height (lift) if indoor section is above the condenser.

6.Determine the Design Subcool Charging Temperature from the unit nameplate.

7.Locate this value in the appropriate column of the Subcooling Charging Table. Locate your liquid line temperature in the left column of the table, and the intersecting liquid line pressure under your nameplate subcool value column. Add refrigerant to raise the pressure to match the table, or

		R-410A REFRIGERANT CHARGING CHART
LIQUID				DESIGN SUBCOOLING (˚F)
TEMP		8	9		10	11		12	13	14
(˚F)			LIQUID GAGE PRESSURE (PSI)
55		179	182		185	188		191	195	198
60		195	198		201	204		208	211	215
65		211	215		218	222		225	229	232
70		229	232		236	240		243	247	251
75		247	251		255	259		263	267	271
80		267	271		275	279		283	287	291
85		287	291		296	300		304	309	313
90		309	313		318	322		327	331	336
95		331	336		341	346		351	355	360
100		355	360		365	370		376	381	386
105		381	386		391	396		402	407	413
110		407	413		418	424		429	435	441
115		435	441		446	452		458	464	470
120		464	470		476	482		488	495	501
125		495	501		507	514		520	527	533
	Refer to Service Facts or
Installer's Guide for charging method.
							From Dwg. D154557P01 Rev. 2

SUBCOOL CHARGING TABLE CORRECTIONS FOR LINE LENGTH AND RISE

REFRIGERANT LINE LIFT (FEET)

60

50

40

30

25	Add 10 psig to Subcool Charging Table Pressure
20

15Use Design Subcool Value from Table

10

0Subtract 10 psig from S.C. Table Pressure

10 20 25 30 40 60 80

TOTAL REFRIGERANT LINE LENGTH (FEET)

SUBCOOLING CHARGING BELOW 55°F OD AMBIENT – IN HEATING ONLY

1.The Subcool Charging Method in cooling is not recom- mended below 55°F outdoor ambient.

2.The only recommended method of charging at outdoor ambients below 55°F, is to weigh in the charge in the heating mode.

3.Use Nameplate charge plus standard charge adders for line length.

4.Check liquid line temperature and pressure (at the OD valves) to obtain a minimum of 10°F subcooling.

5.Add charge if a minimum of 10°F subcooling is not obtained with the nameplate charge plus line length correction.

6.It is important to return in the spring or summer to accurately charge the system in the cooling mode at outdoor ambients above 55°F.

6 18-BC61D1-1