Product data

REFRIGERANT CHARGING (Multi Split)
WARNING:
To prevent personal injury, wear safety glasses and gloves when handling refrigerant. Do not
overcharge system this can cause compressor flooding.
WARNING:
Service valves must be fully back seated to close service port. There is no Schrader valve at the
service port, and failure to backseat the valve could result in loss of system charge or personal injury.
NOTE:
Do not vent or depressurize unit refrigerant to atmosphere. Remove and recover refrigerant following
accepted practices.
The Multi Split units are factory charged with a full operating charge. Check the system for proper charge level
using the subcooling method. If a refrigerant system must be opened for major service work, first recover
refrigerant in system using accepted practices. Evacuate and dehydrate the system when ready to recharge; then
weigh in the proper refrigerant quantity as marked on the unit data plate for each circuit.
Subcooling Charging Method
1. Operate the unit a minimum of 15 minutes before checking the charge.
2. Measure discharge pressure by attaching an accurate gage to the discharge service port. DO NOT use the
external service valves for this pressure reading.
3. Measure the vapor supply line temperature by attaching an accurate thermistor type or electronic thermometer to
the vapor supply line near the outdoor coil. See Fig #14
4. Refer to Table #7 to find the required subcooling temperature for the unit. Find the point at which the required
subcooling temperature intersects the measured internal discharge service port pressure in Table #8.
5. To obtain the required subcooling temperature at a specific discharge pressure, add refrigerant if vapor supply
line temperature is higher than indicated, or remove refrigerant if temperature is lower than indicated. Allow a
tolerance of ± 3%.