LG THERMA V Split - System 9 Design Application

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_ COMPREHENSIVE APPLICATION AND INSTALLATION MANUAL
LG Electronics
Installation check listConguration
System Design ApplicationsIntroduction
1.12 Design the pipe diameter
Items to check Is it proper to design the pipe diameter? Result
Purpose Check water velocity and pressure drop
Applicants Common
An easy method for selecting the piping diameter is as follows.
- Method by water Velocity (0.3 m/s ~ 3 m/s)
- Method by Pressure drop (40 kPa/m ~ 100 kPa/m)
1. Method by water Velocity (0.3 m/s ~ 3 m/s)
˟ Pipe dia
˞ Velocity
˝ Water flow
˝
Ex) 16 kW Therma V
① Rated water ow rate : 46 lpm
(Δ 5 °C)
② Velocity 1 ~ 1.5 m/s
Select the pipe in the ow velocity
range based on the y-axis ow
line
Result : 25 A or 32 A (Pipe spec)
Remark)
If select 32 A :
1) High material cost
2) Difcult to make layout
If select 20 A :
1) High Pressure drop by high
velocity
2) Noise
˟ Pipe dia
˞ Velocity
˝ Water flow
˝
2. Method by Pressure drop (40 kPa/m ~ 100 kPa/m)
˟ Pipe diameter
ˠ Water velocity
˞ Pressure drop
˝ Water flow rate
Ex) 16 kW Therma V
① Rated water ow rate : 46 lpm
(Δ 5 °C)
② Pressure drop range : 40~100
kPa/m
Select the pipe in the pressure
drop range based on the y-axis
ow line
Considering ow velocity, select
the pipe diameter
Result : 25 A or 32 A (Pipe spec)
Remark)
If select 32 A :
1) High material cost
2) Difcult to make layout
If select 25 A :
1) Higher pressure drop than 32 A
2) Cost-effective
˟ Pipe diameter
ˠ Water velocity
˞ Pressure drop
˝ Water flow rate