Specifications

Installation and operation manual
32
RXYQQ8~20T7Y1B
VRV IV System Air Conditioner
4P345099-1 – 2013.04
14.4. Method for adding refrigerant
14.4.1. Flow chart
INFORMATION
If it is not possible to determine exact piping lengths of the existing field piping, it is difficult to calculate the additional refrigerant charge
exactly as explained above. In such a case, make an estimation based on the known lengths and diameters by using the formula as in
"14.3.1. How to calculate the additional refrigerant to be charged" on page 31 and add the additional refrigerant charge by using the
automatic refrigerant charge function (in cooling mode) ONLY. The unit will provide feedback as explained in this chapter, when the
required refrigerant charge is reached or not.
Make sure that the automatic refrigerant charge (in cooling mode) ambient temperature conditions are fulfilled. See also the information
table in "A. Adding refrigerant by using the automatic charging function" on page 35.
Step 1
• Calculate additional refrigerant
charge amount: R (kg) (see
"14.3. Calculating the
additional refrigerant charge"
on page 31)
Refrigerant overcharge happened
• Recover refrigerant to reach
R=Q
• Go to step 4a
Step 2+3
• Open valve C to field piping via
liquid stop valve
• Execute pre-charging amount:
Q (kg)
• Close valve C if no additional
refrigerant can be charged
Step 4a
• Close valve C
• Charging is finished
• Fill in the amount on the
additional refrigerant charge
label
• Go to test run (see "15.4. Test
operation" on page 43)
R<Q R=Q
R>Q
You want to execute automatic
refrigerant charge?
B A
Step 4b+5
Manual refrigerant charging
method (in cooling operation)
NO YES
Step 4b+5
Automatic refrigerant charging
method
Step 6B
Activate field setting [2-20]=1
Unit will start manual refrigerant
charging operation.
Step 6A
• Push 1x BS2: "888"
• Push BS2 for more than 5
seconds "t01" pressure
equalisation
Step 6B
• Open valve A
• Charge remaining amount of
refrigerant P (kg)
R=Q+P
Depending on ambient conditions,
the unit will decide to perform
autocharge operation in heating
or cooling mode.
Step 6B
• Close valve A
• Push BS3 to stop manual
charging
• Charging is finished
• Fill in the amount on the
additional refrigerant charge
label
• Go to test run (see "15.4. Test
operation" on page 43)
Continued on next page >> Continued on next page >>