Toshiba SHRM R410A Quick Reference page 7

Adding refrigerant
After finishing vacuuming, exchange the vacuum pump with a refrigerant canister and start additional charging of
refrigerant.
Calculation of additional refrigerant charge amount
Refrigerant charge amount at shipment from the factory does not include the refrigerant for pipes at the local site.
For refrigerant to be charged in pipes at the local site, calculate the amount and charge it additionally.
NOTE
If the additional refrigerant amount indicates minus as the result of calculation, use the air conditioner without
additional refrigerant.
After finishing vacuuming, exchange the vacuum pump with a refrigerant canister and start additional charging of
refrigerant.
Calculation of additional refrigerant charge amount
Additional refrigerant charge
(lbs)
amount
Table 1
Liquid pipe outer dia.
Additional refrigerant amount/1ft (lbs)
Table 2
Outdoor unit capacity type
072 type
096 type
120 type
144 type
168 type
192 type
216 type
240 type
Example:
(120 type)
L1 Ø1/2": 90ft
a1 Ø1/4": 30ft
a2 Ø1/4": 15ft
Additional charge amount (lbs) = { (Lx × 0.017 lbs/ft)+(Ly × 0.037 lbs/ft)+(Lz × 0.071 lbs/ft) } × 1.3+ 27.5 (lbs)
= { ((a2+d2) × 0.017 lbs)+((L3+a1+b1+c1+d1+b2+c2) × 0.037 lbs)+(L1+L2) × 0.071 lbs } × 1.3+27.5 (lbs)
= { (30 × 0.017 lbs)+(150 × 0.037 lbs)+(135 × 0.071 lbs) } × 1.3+27.5 (lbs)
= 47.84 lbs
Selection of installation place
• The cooling performance may decline considerably when total operating capacity of cooling indoor units is less
than 38 kBtu/h while ambient temperature is below 32°F (0°C).
Actual length of liquid
=
pipe
Ø1/4" Ø3/8"
0.017 0.037
Adjustment amount of refrigerant
(lbs)
5.5
20.9
27.5
5.5
23.1
30.8
34.1
37.4
L2
L1
a1
a2
L2 Ø1/2": 45ft
b1 Ø3/8": 30ft
b2 Ø3/8": 15ft
Lx : Actual total length of liquid pipe Ø1/4" (ft)
Ly : Actual total length of liquid pipe Ø3/8" (ft)
Lz : Actual total length of liquid pipe Ø1/2" (ft)
Additional refrigerant charge
×
amount per liquid pipe 1ft
[Table 3]
Ø1/2" Ø5/8" Ø3/4"
0.071 0.108 0.168
Combined outdoor units
072 type
096 type
120 type
072 type
096 type
096 type
120 type
120 type
d1
L3
b2 c1
b2 c2
L3 Ø3/8":30ft
c1 Ø1/4": 15ft
c2 Ø1/4": 15ft
Adjustment amount of
× +
1.3
refrigerant
[Table 4]
—
—
—
072 type
072 type
096 type
096 type
120 type
FS unit
d2
d1 Ø1/4": 15ft
d2 Ø1/4": 15ft
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