System Design; Piping - Mitsubishi Electric PUD-P-YMF-C Manual

8. System Design

8-1.Piping

Sample Unit Connection
Maximum Pipe Length (L)
Maximum Height
Difference Between
Indoor and outdoor units (H)
I Selecting Refrigerant Pipes
I Adding the Refrigerant
The outdoor unit is shipped with 8.5 kg of
refrigerant. It does not include enough
refrigerant for extra piping system.
Use additional refrigerant for each
refrigerant piping system (2 refrigerant
circuits).
Record the length of the pipe and the
amount of the added refrigerant on the
outdoor unit for services in the future.
I Calculating the amount of refrigerant to
be added
· The amount of refrigerant needed for
additional piping depends on the diameter
and the length of the added liquid pipes.
· Calculate the amount to be added as
shown on the right, and add the refrigerant
in that amount.
· Round up the figure under 0.1kg.
(e.g. 11.06kg would be 11.1kg).
Caution
Charge Liquid Refrigerant
Filling the equipment with gas refrigerant will result in a power loss due to transformation of refrigerant in the tank.
Outdoor Unit
A
A
L
L
Net length: under 120m, Total Length: under 150m
Under 50m
(Under 40m if the outdoor unit is installed below the indoor unit.
Under 15m if the outdoor temperature is under 10˚C.)
ø 28.58 ✕ 2
Gas pipe:
ø 12.7 ✕ 2
Liquid pipe:
<The amount of refrigerant to be added>
Size of the liquid pipe
Total length of the pipe with a diameter of ø 12.7 ✕ 0.12
(m) ✕ 0.12 (kg/m)
(i.e.) When using a 120m pipe with a diameter of ø 12.7
✕
120m 0.12kg/m + 2.0kg = 16.4 kg
17
Indoor
+ 2.0kg