5.9 Additional Refrigerant Charge
1. Charge additional refrigerant in the liquid state.
2. Be sure to use a scale to measure the filling amount when adding refrigerant. If you cannot charge all
refrigerant with the outdoor unit lying idle, charge it with the unit running in the test run mode. If operated for a
long time with insufficient refrigerant the compressor will be damaged. (In particular, when adding refrigerant
during operation, complete the job within 30 min.)
3. Fill this unit only with the standard amount of refrigerant (piping length 0 m fill quantity).
Determine the amount of refrigerant to be charged additionally using the following formula and put down the amount of refrigerant added on the refrigerant charge volume recording plate provided on the back of the side panel.
Additional charge amount
http://farm4.static.flickr.com/3285/...a5b47f_o_d.jpg
Calculation of amount of refrigerant to be charged in local piping
The amount refrigerant additionally charged in local piping depends on connection pipe size but not on indoor
unit type.
[Amount of refrigerant to be charged in the local piping = Actual length of liquid pipe × Amount of refrigerant
additionally charged per meter of liquid pipe]
[Example] Amount of refrigerant additionally charged = (R1 × 0.35) + (R2 × 0.25) + (R3 × 0.17)
+ (R4 × 0.11) + (R5 × 0.054) + (R6 × 0.022)
R1: Overall length (m) of φ 22.22 liquid pipe
R2: Overall length (m) of φ 19.05 liquid pipe
R3: Overall length (m) of φ 15.88 liquid pipe
R4: Overall length (m) of φ 12.7 liquid pipe
R5: Overall length (m) of φ 9.52 liquid pipe
R6: Overall length (m) of φ 6.35 liquid pipe
Pay attention to the following points in addition to the above for the R410A and compatible machines.
To prevent a different oil from entering, please assign dedicated tools, etc. to each refrigerant type. Under no
circumstances must a gauge manifold and a charge hose in particular be shared with other refrigerant types
(R22, R407C, etc.).
Do not use a charge cylinder under any circumstances. There is a danger that the composition of the
refrigerant will change when R410A is transferred to a cylindser.
When charging refrigerant, use liquid refrigrent from a cylinder. If refrigerant is charged in a gas form, the
composition may change considerably.
