1.
After the system has been properly evacuated. Calculate the proper charge by
following the steps of the tables below.
Add the amount of refrigerant needed for the evaporator & condenser + the line-set
then multiply by .80.
Step 1: Select the model and refrigerant charge for evaporator and condenser.
Model
GUAX-022XX
GUAX-036XX
GUAX-045XX
GUAX-070XX
GUAX-091XX
GUAX-125XX
Step 2: Since the majority of refrigerant weight is in liquid form in the liquid line, refrigerant
in the hot gas line and suction line is ignored in the charging calculation.
Calculate the total of the liquid line run, then multiply the equivalent feet of line based on
line size by the correct multiplier to get the refrigerant weight needed for the Line-set.
Example: If the liquid line of an R-410A system is 150ft of 1-1/8" pipe, then multiply 150 *
0.38 = 57lbs
Step 3: Add refrigerant weights from step 1 and 2 together and multiply by .80 to get the
starting charge.
Example: model GUAX-125XX (37.5 + 57 lbs.) *.80 = 75.6 lbs.
2.
Next connect the refrigerant tank to the refrigerant manifold gauge set and make sure the
manifold gauge set is properly purged
3.
Then from a vacuum, slowly open the high side liquid line valve on the refrigerant manifold
gauge to feed liquid refrigerant through the high side.
4.
Add the amount of refrigerant weight per tables, slowly open the high side liquid line valve
on the refrigerant manifold gauge to feed liquid refrigerant through the high side.
Weight of Refrigerant in Evap + Condenser
1. Weight of Refrigerant in Liquid Line (lbs. /ft.)
Liquid Line OD (inches)
1/2"
5/8"
3/4"
7/8"
1-1/8"
Starting Charge (lbs.)
NA
NA
NA
25
32.5
37.5
Multiplier
.067
.107
.160
.223
.380
35
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