5.6 Refrigerant charge
After vacuuming and charging the condensing unit oil, charge the refrigerant as follows.
5.6.1 Confirmation of refrigerant bomb
• Bombs are designated by color depending on kinds of refrigerant. Bomb containing CO2 is painted in green.
• Kind of refrigerant is also stamped on the bomb according to the provision of container inspection.
• Use a refrigerant that satisfies the conditions “Purity > 99.95 (vol%), Moisture < 0.005 (vol%)”.
5.6.2 Weight check of refrigerant bomb
• Use a weight whenever the refrigerant is charged, and charge in the specified quantity as calculated with the following equation.
5.6.3 Calculation of refrigerant charge quantity
Calculate the charge quantity with the following equation.
Refrigerant charge quantity (kg) = Standard refrigerant quantity of condensing unit + Refrigerant quantity for show case or unit
Piping refrigerant quantity.
Regarding these refrigerant quantities, refer to 1, 2 and 3.
1. Standard refrigerant quantity of condensing unit
Standard refrigerant quantity of condensing unit (kg)
Evaporation temperature setting ≤ -5°C
Evaporation temperature setting > -5°C
10.2
12.2
2. Refrigerant quantity for connected show case or unit cooler
Refrigerant quantity for connected show case or unit cooler
Check the total capacity (ℓ) of show cases and unit coolers to be connected. Calculate the charge quantity by multiplying the refrigerant
charge rate.
Refrigerant of show cases or unit coolers to be connected = Total capacity of show cases or unit coolers to be connected (ℓ) x Refrigerant
charge rate
* Refrigerant charge rate of show cases or unit coolers: 0.2 (kg/ℓ)
3. Piping refrigerant quantity
Piping refrigerant charge quantity is calculated from the specifications of liquid pipe of connecting pipe (pipe size) and the length of
each pipe.
Piping refrigerant charge quantity (kg) = Additional charge quantity/m of Ø6.35 (kg/m)Ø x L1 + Additional charge quantity/m
of Ø9.52 (kg/m) x L2 + Additional charge quantity/m of Ø12.7 (kg/m) x L3 + Additional
charge quantity/m of Ø15.88 (kg/m) x L4 + Additional charge quantity/m of Ø19.05
(kg/m) x L5
L1: Total length of Ø6.35 (m), L2: Total length of Ø9.52 (m), L3: Total length of Ø12.7 (m), L4: Total length of Ø15.88 (m), L5: Total length of
Ø19.05 (m)
5. System design recommendations
39
AB408540130380en-000102
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