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COMPREHENSIVE APPLICATION AND INSTALLATION MANUAL
LG Electronics
Installation check list
Configuration
System Design
Applications
Introduction
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 flow rate : 46 lpm
(Δ 5 °C)
②
Velocity 1 ~ 1.5 m/s
Select the pipe in the flow velocity
range based on the y-axis flow
line
Result : 25 A or 32 A (Pipe spec)
Remark)
If select 32 A :
1) High material cost
2) Difficult 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 flow 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
flow line
Considering flow velocity, select
the pipe diameter
Result : 25 A or 32 A (Pipe spec)
Remark)
If select 32 A :
1) High material cost
2) Difficult 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
