23
Branch Pipe Kit Calculation
Add .22 lbs per EACH liquid line branch pipe for additional charge calculation.
Table 4. Refrigerant Charge Adjustment
Liquid Line
Pipe Size
Additional Refrigerant Per Foot of
Pipe Length
1/4 in. 0.015 lb.
3/8 in. 0.040 lb.
1/2 in. 0.080 lb.
5/8 in. 0.120 lb.
3/4 in. 0.181 lb.
7/8 in. 0.255 lb.
Additional Refrigerant Charge
When refrigerant piping connections have been
completed, it will be necessary to adjust the system
refrigerant charge based on the diameter and length
of the liquid line pipe between the outdoor and indoor
unit(s).
Table 4 lists the refrigerant piping sizes along with
the refrigerant adjustment required per foot of liquid
line pipe.
This system is suitable for use with R-410A
refrigerant only.
1. Calculate the additional refrigerant charge using
the diameter and length of the liquid pipe (only)
using Table 4 below.
2. Calculate the additional refrigerant charge for
each liquid line branch pipe kit.
3. If the ratio of VMDB or V33B Indoor unit capacity
exceeds 80% of all indoor units, use Table 5 to
determine the additional refrigerant charge to
add.
4. Total all calculations.
5. Add the calculated additional refrigerant to the
system.
Liquid Line Length Calculation
Calculate additional refrigerant charge using the diameter and length of the liquid pipe.
Table 5. VMDB or V33B Indoor Unit Capacity Ratio over 80% of All Indoor Units
Additional Charge Amount
Outdoor Unit
Module
Pounds (lbs) of additional
refrigerant if ratio of VMDB
Indoor units exceeds 80% of all
indoor units.
Pounds (lbs) of additional
refrigerant if ratio of V33B
indoor units exceeds 80% of all
indoor units.
VPB036H4M-3P 0.88 1.76
VPB048H4M-3P 1.1 2.2
VPB060H4M-3P 1.1 2.2