LG WH20S F5 User manual

OWNER’S MANUAL
HEAT PUMP
WATER HEATER
Read this owner’s manual thoroughly before operating the
appliance and keep it handy for reference at all times.
www.lg.com
Copyright © 2023 LG Electronics Inc. All Rights Reserved.
LG Electronics Inc. Single Point of Contact (EU/UK) :
LG Electronics European Shared Service Center B.V.
Krijgsman 1, 1186 DM Amstelveen, The Netherlands
Original instruction
EN ENGLISH FR FRANÇAIS
IT ITALIANO PL POLSKI
ES ESPAÑOL DE DEUSTSCH
MFL71409209
Rev.00_090823

TABLE OF CONTENTS
SAFETY INSTRUCTIONS ................................................3
Safety Precaution.....................................................................................................4
INSTALLATION ..............................................................12
Parts and Functions ...............................................................................................12
Installation Tools.....................................................................................................13
Accessories............................................................................................................13
Installation Instructions...........................................................................................14
Select the best Location.........................................................................................15
Unpacking and Removing Shipping Bolts ..............................................................16
Thermal Expansion ................................................................................................16
Installing Drain Valve..............................................................................................16
Installing T&P Relief Valve .....................................................................................16
Installing Condensate Drain Lines .........................................................................18
Connecting the Water Supply.................................................................................19
Making Electrical Connections ...............................................................................20
Safety Controls.......................................................................................................21
Insulation Blanket Kits............................................................................................21
Installation Checklist ..............................................................................................22
OPERATION ...................................................................23
Using Basic Control................................................................................................23
SMART FUNCTIONS .....................................................25
LG ThinQ Application .............................................................................................25
MAINTENANCE .............................................................27
Draining and Flushing the Water Heater ................................................................27
T&P Relief Valve Maintenance...............................................................................28
Air Filter Maintenance ............................................................................................28
Condensate Drain Maintenance.............................................................................29
Shut-down for an Extended Period ........................................................................29
TROUBLESHOOTING ...................................................30
Before Calling for Service ......................................................................................30
Error Code..............................................................................................................32
Replacement Parts List ..........................................................................................33
Technical specification ...........................................................................................35
This manual may contain images or content
different from the model you purchased.
This manual is subject to revision by the
manufacturer.

EN
SAFETY INSTRUCTIONS
Your safety and the safety of others are very important.
We have provided many important safety messages in this manual
and on your appliance. Always read and follow all safety messages.
This is the safety alert symbol.
This symbol alerts you to potential hazards that can kill or
injure you and others. All safety messages will follow the
safety alert symbol and either the word DANGER,
WARNING or CAUTION. These words mean:
CAUTION
You may be slightly injured or cause damage to the product if
you do not follow instructions.
WARNING
You may be killed or seriously injured if you do not follow
instructions.
DANGER
This indicates that the failure to follow the instructions will cause
serious injury or death.
All safety messages will tell you what the potential hazard is, tell
you how to reduce the chance of injury, and tell you what may
happen if the instructions are not followed.
!
!
!
!
3

DANGER
Water temperature above 50 °C can cause severe burns
instantly or death from scalding. Be sure to read and follow
the warnings on the picture below.
!
DANGER
Water temperature over 50 °C can
cause instant severe burns or even
death from scalding.
Children, disabled and the elderly are at
highest risk of scalding.
See owner’s manual before setting
temperature at water heater.
Feel water before bathing or showering.
Temperature limiting valves are
available, see manual.
HOT
BURN
4
EN
Safety Precaution
Water Temperature Setting
WARNING
To reduce the risk of explosion, fire, death, electric shock,
injury or scalding to persons, instructions in this manual
must be followed.
Be sure to fully understand the user’s manual before you
install and operate this appliance. If you have any difficulty in
understanding or following the instructions in this manual, or
have any questions, contact an authorized service center or
the local electric utility.
!

5
EN
Temperature Time to Produce a Serious Burn
49 °C More than 5 minutes
52 °C 1 ½ to 2 minutes
54 °C About 30 seconds
57 °C About 10 seconds
60 °C Less than 5 seconds
63 °C Less than 3 seconds
65 °C About 1 ½ seconds
dnoces1tuobAC°86
For determining the proper water temperature for your home,
refer to the chart below.
NOTE
• To reduce point of use water temperature, Thermostatic
Mixing Valves are recommended. These valves automatically
mix hot and cold water in branch water lines. It is
recommended to useamixing valve.
DANGER
Households with the elderly, children, or people with
disabilities may requirea48 °C or lower thermostat setting to
prevent contact with “HOT” water.
!
DANGER
Higher water temperature increases the potential for Hot
Water SCALDS
Water temperature in the heater is regulated by the buttons on
display. The water temperature of this water heater is factory
set to 50 °C to comply with safety regulations. For information
about adjusting the water temperature, refer to the operation
section in this manual.
!

6
EN
Local Installation Regulations
IMPORTANT SAFETY INSTRUCTIONS
This appliance must be installed accordance with instructions
of this manual, national regulations, and any regulations
issued by local authorities and public health bodies.
WARNING
To reduce the risk of explosion, fire, death, electric shock,
scalding or injury to persons when using this product,
follow basic precautions, including the following:
!
Children in the Household:
This appliance is not intended for use by persons (including
children) with reduced physical, sensory or mental capabilities, or
lack of experience and knowledge, unless they have been given
supervision or instruction concerning use of the appliance by a
person responsible for their safety. Children should be
supervised to ensure that they do not play with the appliance.
Take care so that children may not step on the product.
Otherwise, children may be seriously injured due to falling down.
For use in Europe:
This appliance can be used by children aged from 8 years and
above and persons with reduced physical, sensory or mental
capabilities or lack of experience and knowledge if they have
been given supervision or instruction concerning use of the
appliance in a safe way and understand the hazards involved.
Children shall not play with the appliance. Cleaning and user
maintenance shall not be made by children without supervision.

7
EN
Installation
• To reduce the risk of severe injury or death, follow all
installation instructions.
• Be sure your appliance is properly installed in compliance with
local codes and the provided installation instructions.
• Do not replace any part of your water heater and use only
original accessories and spare part unless it is specifically
recommended in this manual.
• Do not turn on the electrical power to water heater unless the
tank is completely full of water.
• Never attempt to operate this appliance if it is damaged,
malfunctioning, partially disassembled, or has missing or
broken parts.
• When the product is soaked (flooded or submerged) in water,
contact an Authorized Service Center for repair before using it
again.
• Moving or installation of the appliance requires two or more
people.
• Turn off the power by opening the circuit breaker or removing
the fuses before installing.
• Even if the water heater thermostat is set to relatively low, hot
water has the potential for scalding. To reduce the risk of
scalding, thermostatic mixing valves are recommended.
• Keep packing materials out of the reach of children. Packaging
material can be dangerous for children. There is a risk of
suffocation.
• Destroy the carton, plastic bag, and other packing materials
after the appliance is unpacked. Children might use them for
play. Cartons covered with rugs, bedspreads, or plastic sheets
can become airtight chambers.
• Connect to a properly rated, protected, and sized power circuit
to avoid electrical overload.

8
EN
• Thisappliance must be positionednear to an electrical power
supply. Use a power supply of 1.5 mm2or more in the nominal
cross-sectional area
• Do not install the water heater on an unstable surface or in a
place where there is danger of it falling.
• For installation, always contact the dealer or an Authorized
Service Center. There is risk of fire, electric shock, explosion or
injury.
• Do not install the water heater in a place where flammable
liquids or gases such as gasoline, propane, paint thinner, etc.,
are stored.
• Always ground the product. There is risk of fire or electric shock
• Install the panel and the cover of the control box safety.
• Do not touch heat exchanger fins with your bare hands.
Otherwise, you may get a cut in your hands.
• Do not input air or gas into the system except with the specific
refrigerant.
• Do not turn on the circuit breaker or power when covers are
removed or opened.
• Make the connection securely so that screw in terminals may
not be loosed when pulling cable.
• There is a risk of fire and explosion. Insert gas (nitrogen) should
be used when you check plumbing leaks, cleaning or repairs of
pipes etc. If you are using combustible gases including oxygen,
product may have the risk of fires and explosions.
Operation
• Usethisapplianceonlyforitsintended purpose.
• If the water heaterhas been subjectedtofire, floodorphysical
damage, disconnect all power to water heaterimmediately, and
DO NOToperate itagain untilithas been inspected by a
qualifiedperson.

9
EN
• Do not turn on the water heater unless the tank is completely
full of water.
• Do not turn on the water heater if cold water supply shut-off
valve is closed.
• Feel water before bathing or showering.
• Even at 50 °C, hot water can scald.
• Do not block the inlet or outlet of air flow.
• Never touch, operate, or repair the water heater with wet
hands.
• Do not leave flammable substances such as gasoline, benzene,
or thinner near the water heater. (Do not install the unit in
potentially explosive atmospheres.)
• Cut off the power supply if there is any noise, smell, or smoke
coming from the water heater.
• Make sure that the power cable is neither dirty, loose, nor
broken.
• Do not place any objects on the power cable.
• Do not modify or extend the power cable. Scratches or peeling
insulation on the power cables may result in fire or electric
shock, and should be replaced.
• The supply cord cannot be replaced. If the cord is damaged the
appliance should be scrapped.
• Do not expose people, animals, or plants to the cold wind from
the water heater for extended periods of time.
• Take care to ensure that power cable could not be pulled out or
damaged during operation. There is risk of fire or electric shock.
• Do not touch refrigerant pipe, water pipe and any internal parts
while the unit is operating or immediately after operation. There
is risk of burns or frostbite, personal injury.
• Additional refrigerant injection is not possible.

10
EN
Maintenance
• If the supply cord is damaged, it must be replaced by the
manufacturer, its service agent or similarly qualified persons in
order to avoid a hazard.
• Disconnect this appliance from the power supply before
cleaning and attempting any user maintenance.
• Before draining water heater, turn off the power to product.
• Do not turn on the electrical power to the water heater unless
the tankis completely full of water.
Technical Safety
• Installation or repairs made by unauthorized persons can pose
hazards to you and others.
• The information contained in the manual is intended for use by
a qualified service technician who is familiar with the safety
procedures and equipped with the proper tools and test
instruments.
• Failure to read and follow all instructions in this manual can
result in equipment malfunction, property damage, personal
injury and/or death.
CAUTION
To reduce the risk of minor injury to persons, malfunction,
or damage to the product or property when using this
product, follow basic precautions, including the following:
!

11
EN
Installation
• Install the productonafirm andlevel floor.
• Donot install thewaterheater inaplacewhereleakage of the
tank or connections will result in damagetothearea adjacent to
itor tolowerfloors of thestructure. Wheresuch areas cannot
be avoided, it is recommendedthat a suitabledrain pan,
adequatelydrained, beinstalledunderthewaterheater.
• Install the product so that the noise or hot wind from the
appliance may not cause any damage to the neighbors.
Otherwise, it may cause dispute with the neighbors.
• Install the drain hose properly for the smooth drainage of water
condensation.
• Always inspect gas leakage after the installation and repair of
product. Otherwise, it may cause the failure of product.
• In order to avoid a hazard due to inadvertent resetting of the
thermal cut-out, this appliance must not be supplied through an
external switching device, such as a timer, or connected to a
circuit that is regularly switched on and off by the utility.
Operation
• Do not step on the product and do not put anything on it.
• Donot usethis appliance if anypart have been underwater.
Immediatelycontact an AuthorizedServiceCenter for replace
floodedwaterheater. Donot attempt torepairtheunit. It must
be replaced.
• Turnoff the power andwatersupplytowaterheateranddrain
waterheater if theappliance is tobeleft for an extended period
of time, such as during vacations.

Parts and Functions
12
EN
INSTALLATION
Top cover
Air intake vents
Junction box
Air filter
Front panel
Display decor / Control panel
ECO
Upper element cover
Front decor
Lower element cover
Heating element
Opening for drain valve
Water inlet
Opening for T&P relief valve
Water outlet
Condensate drain
Rear panel
Air outlet Vents
6
16
15
14
1211 13
7
3
2
5
17
18
9 10
8
11
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
4

EN
Accessories
Included Accessories:
Recommended Accessories:
Figure Name Figure Name
Screw driver Teflon tape
Spanner Level
Multi-meter
Installation Tools
Figure Name Figure Name
Drain valve T&P relief valve
Figure Name Figure Name
Drain pan Thermal
expansion tank
Pressure
reducing valve
Thermostatic
mixing valve
13
Dielectric Union

14
EN
Installation Instructions
Air filter
Display
Primary condensate
drain line (3/4” PVC)
Secondary condensate
drain line (1/2” PVC)
0.5 m Minimum clearance
for installation or service.
Ceiling
Flexible connection
recommended
Hot water outlet
* Thermal expansion
tank (if required)
Shut-off valve
Heat trap Min.
0.15 m
Flexible connection
recommended
Cold water inlet
Drain valve
Open drain
T&P relief valve
and discharge line
* In closed system, connect a thermal expansion tank to cold water supply line.
See “Thermal Expansion” Section (p.16).
* If copper piping is used, The dielectric unions(field supply) must be installed at the
water connections.

15
EN
NOTE
• Installation in a confinedspace without
proper ventilation will leadto higher power
consumption.
• Auxiliarydrain pan MUST be installedin
compliance with local codes.
Drain pan kits are available from the store
where the water heater purchased, or any
water heater distributor.
Drain pan shouldnot obstruct cold water inlet
or drain valve.
- Select space where has enough space for
periodicservicing. The air filter, covers, and
front panels can be removedto permit
inspection andservicing.
- Take the weight of the water heater into
account andselect a place where the floor is
strong enough to support the weight of full
water heater.
- The water heater andwater lines shouldbe
protectedfrom freezing andhigh corrosive
elements. Do not install water heater in
outdoor or unprotectedareas.
- Install the water heater close to the area of
the greatest heater water demandandthe
center of plumbing system. Long uninsulated
hot water lines can waste energy.
- Insufficient air exchange will result in
increasedenergyconsumption level.
- The installation site must be over 1 °C.
Minimum Clearances
Minimum room size:
20 m3
0.15 m
0.15 m 0.45 m
0.15 m 0.45 m
0.5 m
Select the best Location
NOTE
• For future service, a minimum 1 m clearance
between any object and the left, right and
back side is recommended.
Ensure the water heater is horizontal using a
spirit level.
Keep level parallel in installing the product.
Otherwise, it may cause vibration or water
leakage. It may cause injury or an accident.

16
EN
This will cause the relief valve to open during
each heating cycle. We recommend installing
an expansion tank to control thermal
expansion.
Connect the thermal expansion tank to the
cold water supply line (see Installation
Instructions).
For additional information, contact installing
contractor, plumbing inspector, or water
supplier.
NOTE
• Drain valve and T&P relief valve is included
in packing box of the water heater.
They must be installed in the opening
provided for this purpose.
Installing T&P Relief Valve
Use T&P relief valve included in packing.
Installing Drain Valve
Thermal Expansion
Determine if a check valve is present on the
inlet water line. Check with your local water
utility. A check valve located in cold water inlet
line will create a “closed water system”.
As water is heated, it creates an increase in
pressure within the water system because the
increased volume of water doesn’t have a
place to go.
Referred to as “thermal expansion”, the rapid
pressure increase can quickly reach the safety
setting of the relief valve.
Unpacking and Removing
Shipping Bolts
NOTE
• Accessories (drain valve and T&P relief
valve) are attached on pallet. Keep it for
installation.
Unpack all shipping materials from the water
heater for proper operation and inspect it for
shipping damage.
1Remove carton and shipping materials.
2Remove the screws from the shipping
brackets.
3Pull out the shipping brackets.
4Slightly tip the water heater and carefully
roll the water heater off the pallet.
ڸ
ڹ
Accessories 1Apply Teflon tape on the G end to prevent
leaking.
2Install the drain valve in the opening
marked “Drain Valve”.
1Apply Teflon tape on the G end to prevent
leaking.
2Install the T&P relief valve in the opening
marked T&P relief valve.

17
EN
Connecting T&P Relief Valve
Discharge Pipe
WARNING
The pressure rating of the relief valve
must not exceed 1 MPa, the maximum
working pressure of the water heater as
specified on the data plate.
!
WARNING
DO NOT connect any valve or other
restriction to the T&P plumbing. DO
NOT connect the T&P plumbing to the
condensate plumbing. It must be
directly piped to an adequate open
drain.
!
Install T&P Relief Valve discharge pipe
according to local codes and the following
instructions.
- The inside diameter of the discharge pipe
must be at least 3/4”.
- The discharge pipe must be approved for hot
water distribution and withstand 100 °C
without distortion.
- The end of the discharge pipe should not be
threaded or concealed and should be
protected from freezing.
- Do not insert or install any type of valve,
restriction, or reducer coupling in the
discharge pipe.
* The water may drip from the discharge pipe
of the pressure-relief device and that this
pipe must be left open to the atmosphere.
* The pressure-relief device is to be operated
regularly to remove lime deposits and to
verify that it is not blocked.
* A discharge pipe connected to the pressure-
relief device is to be installed in a
continuously downward direction and in a
frost-free environment.
2Attach the discharge pipe to outlet of the
T&P relief valve. The discharge pipe must
pitch downward from the valve to allow
complete drainage of both T&P relief valve
and discharge pipe.
3The end of the discharge pipe must be
piped to an adequate open drain.
1Apply Teflon tape on the G end to prevent
leaking.

18
EN
NOTE
• When making drain fitting connectionstothe
drain tubing, DO NOT overtighten.
Overtightening fittings could crack or
damage the condensatedrain pan.
• Condensatefrom this unit is not acidic.
The condensate drain lines and connections
to the drain piping must meet state and local
codes.
Do not reduce the drain line size to less than
the condensate connection size provided.
Ensure that the condensate drain lines
maintain a downward slope for proper
drainage.
The drain line should be insulated to prevent
condensation from forming on the outside of
the drain line.
If no floor drain is available or the drain is
above the level of the condensate line, then a
common condensate pump with a capacity no
less than 7.5 L per day must be installed.
Installing Condensate Drain
Lines
1Apply Teflon tape on the G end to prevent
leaking.
2Attach elbow with 3/4” slip &3/4”G to the
primary drain connection.
3Using an approved sealant, insert the PVC
pipe into the female end. Condensate
drain must be piped to an adequate drain.
4Using 1/2” PVC piping, an elbow with 1/2”
slip & 1/2” G, and an approved sealant,
attach the elbow to secondary drain
connection and insert the PVC pipe into
the female end.

19
EN
Connecting the Water Supply
NOTE
• DO NOT directly solder or braze to hot or cold
water connections. Ifsweat connections are
used, sweat tubingto adapter before installing
the adapter to the hot or cold water
connections on heater. Any heat applied to the
water supply fittings will permanently damage
the internal plastic liningin these ports.
* The maximum pressure in cold water supply
line is 0.8 MPa. If the supply water is greater
than 0.8 MPa, install a pressure reducing valve.
* Connect the water for filling or refilling the
heating system as specified by EN1717/ EN
61770 to avoid contamination of drinking
water by return flow.
Refer to “Installation Instructions” for
suggested typical installation.
To Fill the Water Heater
WARNING
Do not turn on the electrical power to
water heater unless the tank is
completely full of water. The water
heater warranty does not cover damage
or failure resulting from operation with
empty or partially empty tank.
!
For ease of disconnecting the water heater
for service or replacement, the installation
of unions is recommended on the water
connections.
1Check the type ofwater pipes in your
home. Use fittings adequate for the type of
pipe in your home.
2Apply Teflon tape on the Gend to prevent
leaking.
3Connect cold and hot water supply using
3/4” G.
4Install a shut-off valve in the cold water
line near the water heater.
5Install the insulation on the cold and hot
water pipes. Insulating hot water pipe can
increase energy efficiency.
1Make sure that the drain valve on water
heater is completely closed.
2Turn on the cold water supply
3Open each hot water faucet slowly and
allowthe water to run until it flows with a
full stream.
4Let the water run full stream for a few
minutes.
Maximum and minimum water
operating temperatures (°C) 35 / 62
Maximum and minimum water
operating pressure (MPa) - / 0.8
If cooper piping used, The water heater
should always be connected dielectric
connections (filed supply) to avoid corrosion
caused by electric currents common in
copper water pipes.

20
EN
CAUTION
In order to avoid a hazard due to inadvertent
resetting of the thermal cut-out, this
appliance must not be supplied through an
external switching device, such as a timer,
or connected to a circuit that is regularly
switched on and off by the utility.
!
Making Electrical
Connections
WARNING
Disconnect all power before working on
any electrical connections.
!
WARNING
The ground connection is mandatory.
!
WARNING
Never supply power to heating element
directly. Upper and lower heating
elements are installed on the
product.(230 V, 2 kW)
!
16 A30 mA
L1 L2
BR BL
NOTE
• All wiring must conform to European and
national standards, and must be protected by
a 30 mA RCD(Residual current device).
• Means for disconnection must be
incorporated in the fixed wiring in
accordance with the wiring rules.
The water heater must be permanently powered
by electricity to ensure correct operation of the
impressed current titanium anode (ICCP).
Do not turn on power until water heater is
completely filled.
The appliance can only be connected and
operated on a single-phase 230 V AC grid.
The electrical installation will include:
• The installation of a residual current device
(RCD) having a rated residual operating
current not exceeding 30 mA is advisable.
• The rating of the residual current device
(RCD) to be installed
The supply cord cannot be disconnected from
the product.
The supply cord cannot be replaced. If the
cord is damaged the appliance should be
scrapped.