PWFY-34
PWFY-P-NMU-E-BU/PWFY-P-NMU-E-AU (Sept. 2010)
PWF
Y-P-N
MU-E-BU
PWF
Y-P-N
MU-E-AU
11-3-3. Refrigerant and Drain Piping Specifications
11. SYSTEM DESIGN
To avoid condensation, install insulation and antisweating materials on the refrigerant and drain pipes.
When using commercially available refrigerant pipes, be sure to install commercially available insulating material (with a heat-
resistant temperature of more than 212°F (100°C) and thickness given below) onto both the liquid and gas pipes.
Be also sure to install commercially available insulating material (with a form polyethylene’s specific gravity of 0.03 and thickness
given below) onto all pipes that pass through rooms.
1) Select the thickness of insulating material by pipe size.
Model
PWFY-P36NMU-E-BU
PWFY-P36NMU-E-AU
PWFY-P72NMU-E-AU
Gas
ø15.88 (5/8)
ø15.88 (5/8)
ø19.05 (3/4)
Liquid
ø9.52 (3/8)
ø9.52 (3/8)
ø9.52 (3/8)
Drain
ø32 (1-1/4)
Thickness of Insulation Material
More than 10 mm (13/32 in.)
2) If the unit is used on the highest story of a building and under conditions of high temperature and humidity, it is necessary
to use pipe size and insulating material’s thickness more than those given in the table above.
3) Follow customer’s specifications, if applicable.
Refrigerant Piping, Drain Pipe, and Filling Port
(D)
(A)
(B)
(C)
(E)
480 (18-29/32)
100 (3-15/16)
(17-17/32) 191
(4-1/32) 102
114
(4-1/2)
134
(5-9/32)
184 (7-1/4)
206 (8-1/8)*1
(A) Refrigerant piping (gas)
(B) Refrigerant piping (liquid)
(C) Water inlet
(D) Water outlet
(E) Drain outlet
*1: PWFY-P36, 72NMU-E-AU