Table of Contents
Advertisement
• Brazing Material —15 % silver only
• Digital Multimeter and Amp Clamp
PIPING LIMITATIONS
y Outdoor Unit Service Port Detail
For Systems Designed for Heat Recovery Configuration
Multi V Water 5 Piping and Service Ports
Following pages present Multi V Water V piping limitations and are for illustrative purposes only. Designers MUST use LATS when designing LG VRF
LG Multi V Water 5 systems can be configured to operate as either
systems.
a heat pump or a heat recovery system. The piping MUST be
Heat Recovery Outdoor Unit Service Port Diagram.
installed to the correct outdoor unit service ports according to
project specifications or the system will not operate properly. See
Heat Recovery Outdoor Unit Service Port Detail
below for the piping installation differences between heat pump and
heat recovery systems.
ng service port (back
Table 37: Heat Recovery Triple-Frame Connection Pipe Sizes.
e with right hand thread).
Heat Pump Outdoor Unit Service Port Detail
Heat Pump Outdoor Unit Service Port Diagram.
ure vapor piping service
1. Liquid piping service port (back
seated type with right
seated type with right hand thread).
d).
2. Service port NOT used for heat
pump systems. Keep closed and
capped.
g service port (back
3. Vapor piping service port (back
seated type with right hand thread).
e with right hand thread).
4. Stem head access with factory-
provided cap.
access with factory-
5. Schrader ports with factory-
provided cap.
ap.
6. Service port piping to connect to
field piping.
orts with factory-provided
Heat Recovery Outdoor Unit Service Port Detail
rt piping to connect to
Heat Recovery Outdoor Unit Service Port Diagram.
.
1. Liquid piping service port (back
Conditional Applications
seated type with right hand thread).
Conditional applications are computed in LATS. See below for an explanation of when pipes are upsized.
2. Low pressure vapor piping service
If the equivalent length between the first Y-branch to the farthest indoor unit is >131 feet (maximum 295 feet):
port (back seated type with right
• Pipe segment diameters between the first branch and the last branch must be sized up by one. This applies to both liquid and low / high
hand thread).
vapor pipes. If the next size up is not available, or if the pipe segment diameters are the same as main pipe (A) diameters, sizing up is not
3. Vapor piping service port (back
possible.
seated type with right hand thread).
• While calculating total refrigerant piping length, pipe (B) segment lengths between the first Y-branch and second Y-branch, and between the
4. Stem head access with factory-
second Y-branch and the heat recovery unit must be calculated by two.
provided cap.
• Length of pipe (C) from each indoor unit to the closest Y-branch, header, or heat recovery unit ≤131 feet.
5. Schrader ports with factory-provided
• [Length of pipe from water source unit to farthest indoor unit (A+B+C)] - [Length of pipe from water source unit to closest indoor unit
cap.
(A+B+C)] ≤131 feet.
6. Service port piping to connect to
field piping.
© LG Electronics Canada, Inc., North York, ON Canada. All rights reserved. "LG" is a registered trademark of LG Corp.
68 | LIMITS / PLACEMENT
• Refrigerant Recovery Unit and Tank
Piping
Piping Selection
ACR-rated, seamless phosphorous deoxidized copper (UNS
C12200 DHP class) is the only approved refrigerant pipe material
for LG Multi V products. Approved piping will be marked "R-410A
rated" along the length of the tube.
• Drawn temper (rigid) ACR copper tubing is available in sizes 3/8
through 2-1/8 inches (ASTM B 280, clean, dry and capped).
• Annealed temper (soft) ACR copper tubing is available in sizes
1/4 through 2-1/8 inches (ASTM B 280, clean, dry, and capped).
!
NOTE
• Wall thickness must meet local code requirements and be
1
approved for a maximum operating pressure of 551 psi.
• LG recommends soft copper use to be limited to 1/2 inches.
Use hard drawn for larger sizes to avoid sags and kinks that
1
lead to oil trapping.
6
5
6
5
Handling the Piping
2
To avoid operation failure, a VRF system CANNOT have
4
contaminants or moisture in the piping network. Piping must be
kept clean, dry, and air tight. Commercially available piping,
3
4
however, often contains dust and other materials. Clean it with a
dry inert gas, and keep it capped until ready for installation. While
installing, prevent dust, water, or other contaminants from entering
the piping. When cutting the piping, hold it so copper shavings do
not fall into it, and properly remove all burrs with a de-burring tool.
Ream all piping to its full inside diameter; correctly reamed piping
will provide an excellent surface for a tight seal.
When bending piping, try to keep the number of bends to a
minimum, and use the largest radius possible to reduce the
equivalent length of installed pipe. If an obstacle is in the path of
the planned refrigerant pipe run, it is preferable to route the pipe
over the obstacle, with the length of the horizontal section of pipe
above or below the obstacle be a minimum of three (3) times the
longest vertical rise (or fall) at either end of the segment.
Piping Expansion
1
Expansion and contraction must be allowed in the design to avoid
6
5
fitting and piping fatigue failures. A vapor line in a Multi V water
system can change from 50° to 170° when switching from cooling
2
to heating. This can cause up to 1-3/8 inches expansion /
contraction per 100 feet of pipe, or about 0.001 inch / °F per 10 feet
4
of pipe. When a segment of pipe is mounted between 2 fixed
3
points, provisions must be provided to allow pipe expansion to
naturally occur, generally by expansion Loops or U-bends.
Flaring the Piping
When flaring the piping, use a dedicated R-410A flaring tool; use
only synthetic oil between the nut and the flare (not inside the
piping) to achieve correct torque and prevent leaks. Flares must be
deeper to handle the higher pressures of R-410A.
When brazing the piping, always use 15%
silver braze and a nitrogen purge. Similar to
piping medical gas, flow the nitrogen
through the piping at 1 to 3 psig to prevent
oxidation.
Ream all piping to its full inside diameter; correctly reamed piping
will provide an excellent surface for a tight seal.
When bending piping, try to keep the number of bends to a
minimum, and use the largest radius possible to reduce the
equivalent length of installed pipe. If an obstacle is in the path of
the planned refrigerant pipe run, it is preferable to route the pipe
Dual-frame and triple-frame systems must be installed with all water source units located next to each other. In conditions where the
dual-frame or triple-frame water source units need to be separated, the following rules must be followed.
over the obstacle, with the length of the horizontal section of pipe
These rules do not apply to single-frame Water Source Units.
above or below the obstacle be a minimum of three (3) times the
Measurements
longest vertical rise (or fall) at either end of the segment.
1. All measurements must be made from the union center of the water source unit
Y-branch.
Piping Expansion
Expansion and contraction must be allowed in the design to avoid
Maximum pipe length
fitting and piping fatigue failures. A vapor line in a Multi V water
2. Maximum pipe length from first water source unit Y-branch to farthest water
source unit.
system can change from 50° to 170° when switching from cooling
• Total pipe length from the first outdoor unit Y-branch to the piping connection at
2
the farthest outdoor unit must not exceed thirty-three (33) feet.
to heating. This can cause up to 1-3/8 inches expansion /
Figure 31: Maximum Pipe Length from First WSU Y-branch to Farthest WSU.
contraction per 100 feet of pipe, or about 0.001 inch / °F per 10 fee
of pipe. When a segment of pipe is mounted between 2 fixed
To IDUs/
3
points, provisions must be provided to allow pipe expansion to
HRUs
naturally occur, generally by expansion Loops or U-bends.
33 Feet
(Max.)
Flaring the Piping
When flaring the piping, use a dedicated R-410A flaring tool; use
Trapping
only synthetic oil between the nut and the flare (not inside the
1. When required, all traps must be inverted type traps ≥8" in the vapor line(s).
piping) to achieve correct torque and prevent leaks. Flares must be
a. Heat pump water source units would be trapped in the
suction vapor line, and heat recovery water source units would be trapped in the high AND low pressure
deeper to handle the higher pressures of R-410A.
vapor lines.
b. Inverted traps are defined as any piping that is ≥8" in a vertical direction up the horizontal pipe it elevates from.
When brazing the piping, always use 15%
Figure 32: Traps for Multi V Water V Units
Heat Pump
silver braze and a nitrogen purge. Similar to
To
S uction
piping medical gas, flow the nitrogen
Indoor
Units
through the piping at 1 to 3 psig to prevent
L iq uid
oxidation.
Proper R-410A Flare.
.
REFRIGERANT PIPING FOR SEPARATED
Heat Recovery
To H eat Recov ery Units
H igh Pressure Vapor
L ow Pressure Vapor
Oil Traps
Oil Trap
Oil Trap
L iq uid
© LG Electronics Canada, Inc., North York, ON Canada. All rights reserved. "LG" is a registered trademark of LG Corp.
WATER SOURCE UNITS
Figure 30: Y-branch Measurement Location.
Elevation difference
3. Elevation difference between water source units.
• The elevation difference between the highest and
lowest elevation water source unit must not exceed
sixteen (16) feet.
Figure 34: Elevation Difference Between WSUs.
16 Feet
(Max)
To IDUs/
HRUs
Proper R-410A Flare.
Figure 33: Close Up of An Inverted Oil Trap.
Oil Trap
8 inches
LIMITS / PLACEMENT | 69
Advertisement
Table of Contents
