HP A0554832 manual Refrigerant Charge Determination

Refrigerant Charge Determination. The approximate amount of refrigerant charge required by the system varies based on the total length of the refrigerant lines and the size of the chiller. Referring to Figure 5, determine the amount of charge based on the horsepower of the chiller and the amount of charge based on discharge and liquid line sizes and lengths. Add these three numbers together to find the final operating charge. The final operating charge must be verified by running the system and checking the liquid line sight glass.

Figure 5: Refrigerant Charge Determination

Chiller Condenser Charge Field Installed Piping Charge

Horsepower	Lbs. of
	R-22
5	5.9
7.5	6.1
10	10.8
15	12.6
20	21.2
25	24.2
30	40.2
35	41.2
40	50.2

Pipe O.D.	Discharge Line	Liquid Line
Inches	c R-22(Lbs.)	c R-22(Lbs.)
1/2”	-	7.2
5/8”	-	11.5
7/8”	1.6	24.0
1 1/8”	2.7	40.9
1 3/8”	4.0	62.2
1 5/8’	5.7	88.1
2 1/8”	10.0	153.0
2 5/8”	15.0	236.0

cBased on 100 feet of pipe, 100 ºF Liquid, 100 ºF Discharge

Oil Charge Determination. The remote air-cooled portable chillers are factory charged with the amount of oil required without field-installed piping. Additional oil required is dependent on the amount of additional refrigerant added.

Calculate the amount of additional oil required by using the following formula: Pints of oil (Sunisco 3GS) = lbs. of R-22 added for field installed piping / 100.

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