Calculation Of The Refrigerant Charge; Temperature Loss By Refrigerant Pipe Length - Panasonic PAW-VP1000LDHW Technical Manual

5.2

Calculation of the refrigerant charge

How to calculate refrigerant charge
Example 1:
PAW-VP1000LDHW and U-250PZH2E8
Tubing lengths L = 25 m
(7.5 m – 25 m = 17.5 m)
Find the liquid tube size and additional
charge from the tables below.
17.5 m × 80 g = 1400 g
1400 g – 1500 g = –100 g
Total amount to recover 100g
5.3

Temperature loss by refrigerant pipe length

If the discharge pipe is well insulated between
the heat pump and the tank, the heat loss is
approximately 0.2 ˚C per meter.
PAW-VP•LDHW - Technical Manual – 2019-11
Tubing Data and Refrigerant
Example 2:
PAW-VP750LDHW and U-250PZH2E8
Sample tubing lengths L = 10 m
(7.5 m – 10 m = 2.5 m)
Find the liquid tube size and additional
charge from the tables below.
2.5 m × 80 g = 200 g
200 g – 1500 g = 1300 g
Total amount to recover 1300 g
Outdoor unit
Tubing length (L)
DHW (Tank)
81
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