Nortek GFU18USV4DH Service manual

Nortek Global HVAC, LLC
Installation Instructions / Owner's Manual
Heat Pump
ƽPlease read this owner’s manual carefully before operation and retain it for future reference
ƽSpecifications & illustrations subject to change without notice or incurring obligations
ƽIf you have lost the owner’s manual, please visit www.NortekHVAC.com for electronic
version
Indoor Unit
Outdoor Unit
GFU18(5.3)USV4DH GXH18(5.3)USV4DH
GFU24(7.0)USV4DH
GFU30(8.8)USV4DH
GXH24(7.0)USV4DH
GXH30(8.8)USV4DH
GFU36(10.6)USV4DH GXH36(10.6)USV4DH
GFU42(12.3)USV4DH
GFU48(14.1)USV4DH
GXH42(12.3)USV4DH
GXH48(14.1)USV4DH
DC Inverter U-match Series
Floor Ceiling Type Unit
























Contents

1 Safety Precautions ····················································································· 1
2 Outline of the Unit and Main Parts ····························································· 1
3 Pre-Installation Check List ········································································· 2
3.1 Standard Accessory Parts············································································· 2
3.2 Installation Location Selection ······································································· 4
3.3 Pipe Connection Requirement······································································· 5
3.4 Electrical Requirement ·················································································· 6
4 Unit Installation ····················································································································7
4.1 Indoor Unit Installation ··············································································································7
4.2 Outdoor Unit Installation ······································································································· 11
4.3 Connection Pipe Installation ······························································································· 12
4.4 Vacuum and Gas Leakage Inspection ··········································································· 16
4.5 Drain Pipe Installation ············································································································ 18
4.6 Electrical Wiring ························································································································ 20
5 Installation of Controllers ·······························································································25
6 Testing ···································································································································25
6.1 Trial Operation and Testing ································································································· 25
6. 2 Working Temperature Range ···························································································· 27
7 Troubleshooting and Maintenance ············································································27
7.1 Troubleshooting ························································································································ 27
7.2 Routine Maintenance ············································································································· 29

DC Inverter U-match Series Floor Ceiling Type Unit
1
1 Safety Precautions
WARNING NOTICE: Failure to comply with warning notice could result in
property damage, serious personal injury or death.
CAUTION NOTICE: Failure to comply with caution notice could result in
property damage or personal injury.
NOTICE: Failure to comply with notice could result in property damage.
(1).
Instructions for installation and use of this product are provided by the manufacturer.
(2).
Installation must be performed by authorized personnel only.
(3).
Please follow installation instructions as outlined in this manual.
(4).
Connect the indoor unit and outdoor unit with the room air conditioner piping and cord
supplied.
This installation manual describes the correct connections using the supplied parts.
(5).
Installation work must be performed in accordance with national wiring standards by authorized
personnel only.
(6).
If refrigerant leak occurs during installation, ventilate the area immediately
. If the refrigerant
comes in contact with a flame, it produces toxic gas.
(7).
Do not connect power supply until all installation work is complete.
(8). During installation, make sure that the refrigerant pipe is securely attached before you run the
compressor.
zDo not operate the compressor with 2-way or 3-way valve open.
zThis may cause abnormal pressure in the refrigeration cycle that leads to
compressor
damage or personal injury.
(9).
During the pump-down operation, make sure that the compressor is
turned off before you
remove the refrigerant piping.
zDo not remove the connection pipe while the compressor is in operation.
zThis may cause abnormal pressure in the refrigerant cycle that leads
compressor damage
or personal injury.
(10).
When installing the air
conditioner do not mix gases other than the specified refrigerant
(R410A) to enter the refrigerant cycle.
z
If air or other gas enters the refrigerant cycle, the pressure inside the cycle will rise to an
abnormally high value and cause compressor damage or personal injury.
(11).
This appliance is not intended for use by persons (including children) with reduced physical,
sensory or mental capabilities, or lack of experience and knowledge.
(12).
Children should be supervised to ensure that they do not play with the appliance.
(13).
If the supply cord is damaged, it must be replaced with an appropriately sized cord.
2 Main Parts

DC Inverter U-match Series Floor Ceiling Type Unit
2
Fig. 2.1
Installer must properly connect refrigeration
pipe, drain pipe, power cord, and ductwork.
3 Pre-Installation Check List

DC Inverter U-match Series Floor Ceiling Type Unit
3
3.1 Standard Accessory Parts
The standard accessory parts listed below are furnished and should be used as
described.
Table 3.1
Indoor Unit Accessories
No.
Name Appearance
Q'ty
Usage
1
Nut with Washer
8
To
secure
the hook on the
cabinet of the unit
2
Wireless Con
troller +
Battery
1+2
To control the indoor unit
3
Insulation
1
To insulate the gas pipe
4
Insulation
1
To insulate the liquid pipe
5
Fastener
4
To fasten the sponge
6
Nut
1
To connect gas pipe
7
Nut
1
To connect liquid pipe
Table 3.2
Outdoor Unit Accessories
No.
Name Appearance
Q'ty
Usage
1
Drain Plug
1
or 3
To plug the unused drain
hole
2
Drainage Connecter
or
1
To connect with the hard
PVC drain pipe

DC Inverter U-match Series Floor Ceiling Type Unit
4
3.2 Installation Location Selection
ķ. Check the support structure to verify that it has sufficient load-
carrying capacity to support the
weight of the unit and it can be securely mounted.
ĸ. Do not install where there is a danger of combustible gas leakage.
Ĺ. Do not install the unit near heat source, steam, or flammable gas.
ĺ. Children must not operate the unit.
Decide the installation location with the customer as follows:
3.2.1 Indoor Unit
(1). Check the support structure to verify that it has sufficient load-carrying
capacity to support the weight of the unit.
(2). The air inlet and outlet of the unit should never be blocked so that the
airflow can reach every corner of the room.
(3). Leave service space around the unit as required in Fig. 3.1.
ƹFloor type
ƹCeiling type
Fig. 3.1
(4). Install the unit where the drain pipe can be easily installed.
(5). The more space that is open above the unit, the easier it will be to service.

DC Inverter U-match Series Floor Ceiling Type Unit
5
3.2.2 Outdoor Unit
ķ
. Install the unit where it will not be tilted by more than 5°.
ĸ
. The outdoor unit should be securely mounted to withstand high wind.
If possible, do not install the unit where it will be exposed to direct sunlight. (If
necessary, install a blind that does not interfere with the air flow.)
(1). Install the outdoor unit in a place where it will be free from dirt or rain as
much as possible.
(2). Install the outdoor unit where it is convenient to connect with the indoor
unit.
(3). Install the outdoor unit where the condensate water can be drained out
freely during heating operation.
(4). Do not place animals and plants in the path of the warm air.
(5). Select a location where sound and vibration will have little or no impact.
(6). Check the support structure to verify that it has sufficient load-carrying
capacity to support the weight of the unit. Mount the unit securely to reduce
vibration noise.
(7). Provide the space shown in Fig. 3.2, so that the air flow is not blocked. Also
for efficient operation, leave three of four directions of peripheral
constructions open.
Fig. 3.2
3.3 Pipe Connection Requirement
The maximum length of the connection pipe is listed in the Table below. Do not place
the units
where the distance exceeds the maximum length of the connection pipe.

DC Inverter U-match Series Floor Ceiling Type Unit
6
Table 3.3
Item
Model
Size of Fitting Pipe
mm (inch)
Max.
Pipe
Length
m (feet)
Max. Height
Difference
between Indoor
Unit and Outdoor
Unit
m (feet)
Drainage
pipe(Out
er
Diameter × wall
thickness)
mm (inch)
Liquid
Gas
GFU18(5.3)USV4DH
GXH18(5.3)USV4DH
6(1/4)
12.7(1/2)
50(164)
15(49) Φ17X1.75
(Φ5/8 X 1/16)
GFU24(7.0)USV4DH
GXH24(7.0)USV4DH
9.5(3/8)
16(5/8)
50(164)
15(49) Φ17X1.75
(Φ5/8 X 1/16)
GFU30(8.8)USV4DH
GXH30(8.8)USV4DH
9.5(3/8)
16(5/8)
50(164)
15(49) Φ17X1.75
(Φ5/8 X 1/16)
GFU36(10.6)USV4DH
GXH36(10.6)USV4DH
9.5(3/8)
16(5/8)
50(164)
15(49) Φ17X1.75
(Φ5/8 X 1/16)
GFU42(12.3)USV4DH
GXH42(12.3)USV4DH
9.5(3/8)
16(5/8)
50(164)
15(49) Φ17X1.75
(Φ5/8 X 1/16)
GFU48(14.1)USV4DH
GXH48(14.1)USV4DH
9.5(3/8)
16(5/8)
70(230)
15(49) Φ17X1.75
(Φ5/8 X 1/16)
Notes:
ķ.The connecting pipe should be thermally insulated.
ĸ.The pipe wall thickness shall be 0.5~1.0mm (0.02~0.04inch) and the pipe
wall shall be able to withstand the pressure of 6.0MPa (870psig). The
shorter the connecting pipe, the better the cooling and heating effect.
3.4 Electrical Requirement
Electric Wire Size and Fuse Capacity.
Table 3.4
Indoor Units
Power Supply
Fuse
Capacity
Minimum Circuit
Ampacity
Maximum
Over
current
Protection
V/Ph/Hz
A
A
A
GFU18(5.3)USV4DH
208/230V ~ 60Hz
5
1
15
GFU24(7.0)USV4DH
208/230V ~ 60Hz
5
1
15
GFU30(8.8)USV4DH
208/230V ~ 60Hz
5
2
15
GFU36(10.6)USV4DH
208/230V ~ 60Hz
5
2
15
GFU42(12.3)USV4DH
208/230V ~ 60Hz
5
2
15
GFU48(14.1)USV4DH
208/230V ~ 60Hz
5
3
15

DC Inverter U-match Series Floor Ceiling Type Unit
7
Table 3.5
Outdoor Units
Power Supply
Fuse
Capacity
Minimum Circuit
Ampacity
Maximum
Overcurrent
Protection
V/Ph/Hz
A
A
A
GXH18(5.3)USV4DH
208/230V ~ 60Hz
5
17
25
GXH24(7.0)USV4DH
208/230V ~ 60Hz
5
24
40
GXH30(8.8)USV4DH
208/230V ~ 60Hz
5
24
40
GXH36(10.6)USV4DH
208/230V ~ 60Hz
5
29
45
GXH42(12.3)USV4DH
208/230V ~ 60Hz
5
31
50
GXH48(14.1)USV4DH
208/230V ~ 60Hz
5
45
70
Notes:
ķ.The fuse is located on the main board.
ĸ.Install the disconnect device with a contact gap of at least 3mm (1/8inch) in
all poles nearby the units (Both indoor unit and outdoor unit).The appliance
must be positioned so that the plug is accessible.
Ĺ.Use 2 pieces of power cord of 0.75mm2(AWG18) as the communication
lines between indoor and outdoor unit, with their longest lengths of 50m
(164feet). Please select the appropriate line length per the actual
installation conditions. The communication lines can not be twisted together.
For the unit ( İ30k), it’s recommended to use 8m (26feet) long
communication line.
ĺ.Take 2 pieces of power cord of 0.75mm2(AWG18) as the communication
lines between the wired controller and the indoor unit, with their longest
lengths of 30m (98feet). Please select the appropriate line length per the
actual installation conditions. The communication lines can not be twisted
together. It’s recommended to use 8m (26feet) long communication line.
Ļ.The wire size of the communication line should be no less than 0.75mm2
(AWG18). It’s recommended to take 0.75mm2(AWG18) power cords as the
communication line.
4 Unit Installation
4.1 Indoor Unit Installation
4.1.1 Indoor unit dimension

DC Inverter U-match Series Floor Ceiling Type Unit
8
ķ. Verify that the installation location has sufficient load-
carrying capacity to support five (5) times
the weight of the indoor unit. Mount on surface that will not amplify sound or vibration.
ĸ. If the unit is not mounted secuely, the indoor unit may fall and cause injuries.
Ĺ. If the job is done with the panel frame only, there is a risk that the unit will come loose.
Fig. 4.1
Table 4.1 Unit: mm (inch)
Model
A
B
C
D
H
GFU18(5.3)USV4DH
GFU24(7.0)USV4DH
1220(48)
225(8
-
7/8)
1160(45
-
5/8)
280(11)
700(27
-
1/2)
GFU30(8.8)USV4DH
GFU36(10.6)USV4DH
GFU42(12.3)USV4DH
1420(55
-
7/8)
245(9
-
5/8)
1355(53
-
1/4)
280(11)
700(27
-
1/2)
GFU48(14.1)USV4DH
1700(66-7/8)
245(9-5/8)
1635(64-3/8)
280(11)
700(27-1/2)
4.1.2 Preparation for Installing the Indoor Unit
(1). Open the air inlet grille and the screw cover, and remove the screws.
(2). Release the claws in the 3 places indicated.
(3). Release the center hook and remove the front panel.
(4). Release the claws in the 2 or 3 places indicated and remove the electric
component cover.

DC Inverter U-match Series Floor Ceiling Type Unit
9
4.1.3 Indoor Unit Installation
(1). Determine the location of the hanger with the paper template, and then
remove the paper template.
Fig. 4.2
(2). Insert the anchor bolts into the drilled holes, and drive the pins completely
into the anchor bolts with a hammer.
(3). Remove the right and left side panels.
(4). Put the hanger bolt into the clasp of the indoor unit and tighten screws on
the hanger to prevent the indoor unit from moving.
(5). Reinstall and secure the right and left side panels.
ƹFloor type
Fig. 4.3

DC Inverter U-match Series Floor Ceiling Type Unit
10
ƹCeiling type
Fig. 4.4
(6). Adjust the height of the unit to make the drain pipe slant slightly downward
so that the drainage will become much smoother.
4.1.4 Leveling
The water level test must be done after installing the indoor unit to make sure
the unit is level, as shown below.
Fig. 4.5

DC Inverter U-match Series Floor Ceiling Type Unit
11
4.2 Outdoor Unit Installation
ķ
. Install the unit where it will not be tilted by more than 5°.
ĸ.
During installation, if the outdoor unit has to be exposed to strong wind, it must be securely
mounted.
4.2.1 Outdoor unit dimension

Fig. 4.6
Table 4.2 Unit: mm (inch)
Item
Model
A B C D E
GXH18(5.3)USV4DH
955(37-5/8)
395(15-1/2)
700(27-1/2)
560(22)
360(14-1/8)
GXH24(7.0)USV4DH
980(38
-
5/8)
425(16
-
3/4)
790(31
-
1/8)
610(24)
395(15
-
1/2)
GXH30(8.8)USV4DH
GXH36(10.6)USV4DH
1105(43-5/8)
440(17-3/8)
1100(43-1/4)
630(24-7/8)
400(15-3/4)
GXH42(12.3)USV4DH
960(37
-
3/4)
410(16
-
1/4)
1350(53
-
1/8)
570(22
-
1/2)
375(14
-
3/4)
GXH48(14.1)USV4DH
4.2.2 Outdoor Unit Condensate Drainage (Heat pump unit
only) (Fig. 4.7)
(1). It is required to install a drain pipe for the outdoor unit to drain condensate
water during heating operation (only for the heat pump unit).
(2). All holes, with the exception of the drain pipe hole, should be plugged so as
to avoid water leakage (for heat pump unit only).
(3). Installation Method: Insert the pipe joint into the Φ25mm (1inch) hole

DC Inverter U-match Series Floor Ceiling Type Unit
12
located at the base plate of the unit and then connect the drain pipe to the
pipe joint.
Fig. 4.7
4.3 Connection Pipe Installation
4.3.1 Flare Process
(1). Cut the connection pipe with pipe cutter and remove the burrs.
(2). Hold the pipe downward to prevent cuttings from entering the pipe.
(3). Remove the flare nut from the stop valve on the outdoor unit. Get another
flare nut from the accessory bag for the indoor unit. Insert pipe through flare
nuts. Flare the connection with a flaring tool.
(4). Check if the flare part is spread evenly and there are no cracks (see Fig.
4.8).
Fig. 4.8
4.3.2 Bending Pipes
(1). Extend the pipe by hand. Be careful not to crimp it.
pp
y
y
p
p
p
p
Fig. 4.9
(2). Do not bend the pipes in an angle more than 90°.

DC Inverter U-match Series Floor Ceiling Type Unit
13
(3).
When pipes are repeatedly bent or stretched, the material will
weaken
making it more likely to break
. Do not bend or stretch the pipes more than three
times.
(4).
For best results, cut insulatio
n before
bending, as shown in fig. 4.10
. Bend pipe as
needed and secure insulation with tape.
Fig. 4.10
ķ.
To prevent breaking of the pipe, avoid sharp bends. Bend the pipe with a radius of curvature of
150mm (6inch) or more.
ĸ. If the pipe is bent repeatedly at the same place, it will break.
4.3.3 Connecting the Pipe at the Indoor Unit Side
Detach the caps and plugs from the pipes.
ķ. Be sure to attach the pipe on the indoor unit correctly.
Center the flare nut on the fitting before
tightening. Do not f
orce the nut to turn or the threads will be damaged and the system will leak.
ĸ.
Do not remove the flare nut until the connection pipe is to be connected so as to prevent dust
and impurities from coming into the pipe system.
When connecting the pipe to the unit, use both a torque wrench and a standard
wrench or pliers (Fig. 4.11).
When connecting, smear both inside and outside of the flare nut with
refrigeration oil, tighten it by hand, and then tighten it with the wrench/pliers.
Refer to Table 4.3 to check if the wrench has been tightened properly (too tight
would mangle the nut and lead to leakage).
Examine the connection pipe to see if it leaks, then make heat insulation
treatment, as shown in the Fig. 4.12.
Use the medium-sized sponge to insulate the coupler of the gas pipe.

DC Inverter U-match Series Floor Ceiling Type Unit
14

Fig. 4.11
Fig. 4.12
Table 4.3 Flare nut tightening torque
Pipe Diameter
Tightening Torque
6mm (1/4inch)
15~30N·m (11~22ft.-1b.)
9.5mm (3/8inch)
35~40N·m (26~29ft.-1b.)
12.7mm (1/2inch)
45~50N·m (33~37ft.-1b.)
16mm (5/8inch)
60~65N·m (44~48ft.-1b.)
Be sure to connect the gas pipe after connecting the liquid pipe completely.
4.3.4 Connecting the Pipe to the Outdoor Unit
Tighten the flare nut of the connection pipe at
the outdoor unit valve connector. The tightening
method i
s the same as that as at the indoor
unit.
Fig. 4.13

DC Inverter U-match Series Floor Ceiling Type Unit
15
4.3.5 Checking the Pipe Connections for Gas Leaks
For both indoor and outdoor unit, be sure to check the joints for gas leaks with a
gas leakage detector.
4.3.6 Heat Insulation on the Pipe Joints (Indoor Unit Only)
Attach coupler heat insulation (large and small) to the pipe connections.
Fig. 4.14
4.3.7 Liquid Pipe and Drain Pipe
(1).
If the outdoor unit is installed lower than
the indoor unit (See Fig. 4.15)
1). A drain pipe should terminate
above
ground le
vel without being submersed
into water. All pipes must be
attached
to the wall with clamps/saddles.
2).
Wrap tape around pipe starting at the
bottom and working up.
3). All pipes must be
bound together by
tape and attached to wall
with
clapms/saddles.
Fig. 4.15

DC Inverter U-match Series Floor Ceiling Type Unit
16
(2).
If the outdoor unit is installed higher
than the indoor unit
1).
Wrap tape from the lower end working
up.
2). All pipes must be
bound and taped
together
. A trap must be installed to
prevent water from returning to the
room (See Fig. 4.16).
3). Attach all pipes to th
e wall with
clamps/saddles.
Fig. 4.16
4.4 Vacuum and Gas Leakage Inspection
Do not purge the air with refrigerants but use a vacuum pump to vacuum the installation! There
is no extra refrigerant in the outdoor unit for air purging!
4.4.1 Vacuum
(1). Remove the caps of the liquid valve, gas valve and also the service port.
(2). Connect the hose at the low pressure side of the manifold valve assembly
to the service port of the unit’s gas valve. The gas and liquid valves should
be kept closed in case of refrigerant leak.
(3). Connect the hose used for evacuation to the vacuum pump.
(4). Open the switch at the lower pressure side of the manifold valve assembly
and start the vacuum pump. The switch at the high pressure side of the
manifold valve assembly should be kept closed, otherwise evacuation
would fail.
(5). The evacuation duration depends on the unit’s capacity, generally, 20
minutes for the 18k units, 30 minutes for the 24k/30k/36k units, 45 minutes
for the 42k/48k units. Verify that the pressure gauge at the low pressure
side of the manifold valve assembly reads -1.0MPa (145psig). If it doesn’t, it
indicates there is leak somewhere. If that is the case, close the switch fully,
and stop the vacuum pump.
(6). Wait for some time to see if the system pressure can remain unchanged, 3
minutes for the 18k/24k units, 10 minutes for the 30k/36k/42k/48k units.

DC Inverter U-match Series Floor Ceiling Type Unit
17
During this time, the reading of the pressure gauge at the low pressure side
can not be larger than 0.005MPa (0.72psig).
(7). Slightly open the liquid valve and let some refrigerant into the connection
pipe to balance the pressure inside and outside of the connection pipe, so
that air will not come into the connection pipe when removing the hose.
Note that the gas and liquid valve can be opened fully only after the
manifold valve assembly is removed.
(8). Replace the caps of the liquid valve, gas valve and service port.
Fig. 4.17
Note: For the large-sized unit, it has the service port for both the gas valve and the
liquid valve. During evacuation, it is possible to connect two hoses of the manifold
valve assembly to two service ports to quicken the evacuating speed.
4.4.2 Additional Charge
Refrigerant suitable for a piping length of 7.6m (25feet) is charged in the outdoor
unit at the factory. When the piping is longer than 7.6m (25feet), additional charging
is necessary.
For the additional amount, see Table 4.4.
Table 4.4
Item
Model
Additional Refrigerant Amount for Extra Pipe
18k
45g per 1.5m (1.6 ounce per 5 feet )
24k~48k
90g per 1.5m (3.2 ounce per 5 feet )