Drazice OKCE 80 Specification sheet

OPERATING AND
INSTALLATION MANUAL
TANK-TYPE WATER HEATER FOR VERTICAL
MOUNTING
Electric water heaters
4 kW/400 V
OKCE 80 OKCE 200 OKHE 80
OKCE 100 OKHE 100
OKCE 125 OKHE 125
OKCE 160 OKHE 160
Družstevní závody Dražice-strojírna s.r.o.
(Works Cooperative - Dražice - Machine Plant, Ltd.)
Dražice 69, 294 71 Benátky nad Jizerou
tel.: +420 / 326 370 911
fax: +420 / 326 370 980
e-mail: expo[email protected]

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CONTENTS
1PRODUCT TECHNICAL SPECIFICATION....................................................................................................... 4
1.1 FUNCTION DESCRIPTION ................................................................................................................... 4
1.2 ADVICE FOR CUSTOMERS .................................................................................................................. 4
1.2.1HOT WATER CONSUMPTION..................................................................................................... 4
1.2.2 ENERGY SAVING......................................................................................................................... 4
1.2.3 EMERGENCY POWER CONSUMPTION ....................................................................................... 4
1.3 DESIGN AND GENERAL HEATER DIMENSIONS................................................................................... 6
2OPERATION AND FITTING INSTRUCTIONS.................................................................................................9
2.1 OPERATING CONDITIONS .................................................................................................................. 9
2.2 WALL MOUNTING.............................................................................................................................. 9
2.3 PLUMBING FIXTURE......................................................................................................................... 10
2.4 ELECTRICAL INSTALLATION.............................................................................................................. 12
2.4.1 GENERAL INFORMATION FOR ELECTRICAL INSTALLATION ..................................................... 12
2.5 OPERATING ACTIVITY ...................................................................................................................... 13
2.6 FIRST COMMISSIONING................................................................................................................... 13
2.7 PUTTING OUT OF SERVICE, DISCHARGE .......................................................................................... 14
2.8 INSPECTION, MAINTENANCE & CARE FOR THE APPLIANCE............................................................ 14
2.9 MOST FREQUENT FUNCTION FAILURES AND THEIR CAUSES .......................................................... 15
3OPERATION OF THERMOSTAT................................................................................................................. 16
3.1 SERVICING........................................................................................................................................ 16
3.1.1 TEMPERATURE SETTING .......................................................................................................... 17
4IMPORTANT NOTICES .............................................................................................................................. 18
4.1 INSTALLATION REGULATIONS.......................................................................................................... 18
4.2 TRANSPORT & STORAGE INSTRUCTIONS ........................................................................................ 18
4.3 DISPOSAL OF PACKAGING MATERIAL AND NON-FUNCTIONING PRODUCT.................................... 19
5PRODUCT ACCESSORIES .......................................................................................................................... 19

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CAREFULLY READ THIS MANUAL BEFORE INSTALLING THE WATER HEATER!
Dear Customer,
The Works Cooperative of Dražice - Machine Plant, Ltd., would like
to thank you for your decision to use a product of our brand.
With this guide, we will introduce you to the use, construction,
maintenance and other information on electrical water heaters.
The product is not intended to be controlled by
a) people (including children) with reduced physical, sensual or mental capacities, or
b) people with insufficient knowledge and experiences unless supervised by responsible person,
or unless properly instructed by such responsible person.
The manufacturer reserves the right for engineering modification of the product. The product is designed
for permanent contact with drinkable water.
It is recommended to use the product in indoor environment with air temperatures from +2°C to +45°C
and a relative humidity up to 80%.
Product’s reliability and safety is proven by tests implemented by the Engineering Test Institute in Brno.
Made in the Czech Republic.
Meaning of pictograms used in the Manual
Important information for heater users.
Abiding by the recommendations of the manufacturer serves to ensure trouble-free operation
and the long service life of the product.
Caution!
Important notice to be observed.

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1PRODUCT TECHNICAL SPECIFICATION
1.1 FUNCTION DESCRIPTION
Tank type water heater (the heater hereinafter) is designed for the accumulation heating of service water
by electric energy.Water is heated by an electric element in an enamelled thermally insulated tank
at the time defined by the power supplier. The element is at the time of heating controlled by a thermostat
the temperature of which can be adjusted continuously (within the range between 5 °C and 74 °C). Once
the selected temperature is reached, heating interrupts automatically. Water accumulated in the tank
is then used for consumption. The tank keeps constant pressure of water from the water main.
If the combination faucet hot water valve is opened, water from the water supply conduit pressed out
by cold water pressure flows out of the heater. Hot water flows out through the top part, and water flowing
in remains in the bottom part of the heater. Pressure principle allows hot water withdrawal at any place
from the heater.
1.2 ADVICE FOR CUSTOMERS
1.2.1 HOT WATER CONSUMPTION
Consumption of hot water in households depends on the number of people, amount of sanitary
equipment, length, diameter and insulation of piping in the flat, or on individual habits of users.
The cheapest option of water heating comes at the time when the electricity rate is reduced.
Find out in what time intervals your electricity supplier provides reduced tariff and, depending
on that information, select relevant volume and power input of the heater so that your hot
water consumption covered the needs of your household.
1.2.2 ENERGY SAVING
The heater is insulated with quality polyurethane Freon free foam. Set the temperature
of the heater's thermostat to that level only that you need to run your home. Thus you will
reduce electricity consumption, as well as the amount of lime sediments on the walls
of the receptacle and on the electric body.
1.2.3 EMERGENCY POWER CONSUMPTION
If no heated water is taken from the tank, a small amount of heat leaks. This loss is measured
for a period of 24 hours at the temperature of 65°C in the heater, and at 20°C in its ambient area.
The resulting value is expressed in units [kWh/24h] and indicates the amount of power needed
to maintain the set temperature.

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TYPE OKCE 80
OKHE 80
OKCE 100
OKHE 100
OKCE 125
OKHE 125
OKCE 160
OKHE 160
OKCE 200
VOLUME L 80 100 125 152 200
MAX OPERATING
OVERPRESSURE IN THE TANK MPa 0.6
ELECTRICAL CONNECTION V 3/N/PE ~ 400V/50Hz
RECOMMENDED BREAKER 3x10 A
INPUT W 4000
EL. PROTECTION IP 44
MAX OPERATING
TEMPERATURE OF HOT
WATER (HW)
°C 80
RECOMMENDED HOT WATER
(HW) TEMPERATURE °C 60
HEIGHT OF THE HEATER mm 757
740
902
885
1067
1050
1255
1235 1290
HEATER DIAMETER
(only OKCE) mm 524 524 524 524 584
THE HEATER DIMENSION
width x depth
(only OKHE)
mm 520x550
MAX WEIGHT OF THE HEATER
WITHOUT WATER kg 33/35 40/39 44/46 50/52 67
TIME OF EL. HEATING
FROM 10°C TO 60°C* hrs 1.21.51.82.22.9
LOAD PROFILE M M M L XL
ANNUAL CONSUMPTION
OF ELECTRIC ENERGY kWh 1342
1391
1362
1395
1409
1374
2622
2715
4403
MIXED WATER V40 L 138.7165.41 231.1242.83 331.26
Table 1

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1.3 DESIGN AND GENERAL HEATER DIMENSIONS
The heater tanks are made of a steel plate and tested by 1.5 MPa multiple of operation pressure value.
The inside of the receptacle is enamelled. A flange is welded onto the bottom of the tank with a flange lid
screwed to it. A sealing ring is inserted between the flange lid and the flange. Thermowells for placing
a heating element, thermostat sensors and safety fuses are located in the flange lid. An anode rod is mounted
onto the M8 nut. Electric wiring is placed underneath the plastic removable cover. Description of basic parts
of the heater - Figure 1. Heater dimensions - Figure 2and Table 2, Figure 3and Table 3.
Figure 1
1. Temperature indicator
2. Heating element well
3. Ceramic heating element 4000W
4. Service thermostat with external control
and safety pipe
5. Electric installation cover
6. Cold water supply pipe
7. Thermowell
8. Hot water withdrawal pipe
9. Mg anode
10. Enamelled steel receptacle
11. Polyurethane insulation
12. Heater shell

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OKCE 80, OKCE 100, OKCE 125, OKCE 160, OKCE 200
Figure 2
Table 2
OKCE 80 OKCE 100 OKCE 125 OKCE 160 OKCE 200
A 757 902 1067 1255 1290
B 562 562 562 562 600
C 14 14 14 14 14
D 524 524 524 524 584
E 605 725 760 1000 795
F 508 654 682 925 600
H 142 167 297 245 485
K 116 116 116 116 116
R 450 450 450 450 450
3/4" outer
Upper and lower Hinge 200L
4 anchoring screws
Dimensions 450mm and F
check before drilling
Upper hinge 50 - 160L
2 anchoring screws

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OKHE 80, OKHE 100, OKHE 125, OKHE 160
Figure 3
Table 3
OKHE 80 OKHE 100 OKHE 125 OKHE 160
A 740 885 1050 1235
B 550 550 550 550
C 19 19 19 19
D 520 520 520 520
E 582 727 757 1000
F 464 605 638 880
H 148 148 283 225
K 117 117 117 117
R 450 450 450 450
3/4" outer

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2OPERATION AND FITTING INSTRUCTIONS
2.1 OPERATING CONDITIONS
The tank shall only be used in accordance with the conditions specified on the power plate
and in instructions for electric wiring. Besides legally acknowledged national regulations
and standards, also conditions for connection defined in local electric and water works have
to be adhered to, as well as the installation and operation manual.
The temperature at the place of heater installation must be higher than +2°C; and the room
must not freeze. The appliance has to be mounted at a convenient place, it means
that the appliance must be easily available for potential necessary maintenance, repair
or replacement, as the case may be.
If water is strongly calcareous we recommend that any of the common decalcifying devices
was installed with the appliance, or that the thermostat was set to the minimum operating
temperature of 60oC (setting to position „ECO“ or „OPTIMUM“) - Figure 12, Figure 13. For proper
operation, drinkable water of adequate quality shall be used. To avoid potential sediments we
recommend that the device was installed together with a water filter.
2.2 WALL MOUNTING
Prior to the mounting check the bearing capacity of the wall and the material it is made
of, considering the weight of the heater filled with water. Depending on the wall material choose
adequate fixtures. Should you have any doubts regarding the wall bearing capacity, consult
the suspension with a building specialist. The minimum diameter of the bolts for suspending
the heater is 12 mm. When mounting the anchor bolts follow the guide provided by the anchor
bolts' manufacturer.
Mount the anchors by the dimensional drawing (Figure 2, Figure 3) in 450 mm spacing. The heater verticality
after the release of the connecting screws can be aligned by means of slight turning. Double check the torque
of the suspension bolts on the heater and suspend the heater. Using the detent support in the bottom part
of the heater make sure it runs in parallel with the wall at the heaters OKHE 80-160 l!
Figure 4

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Universal suspension
The use of the suspension even for the screw spacing during the replacement with a heater of another type.
The heater verticality after the release of the connecting screws can be aligned by means of slight turning.
Figure 5
If the hot water heater is mounted in a tight, small space, or in an intermediate ceiling, etc., you
have to make sure that the connecting side of the appliance (connections to water supply, area
for electric plugging) remained accessible and no heat accumulation occurs. Free space of up to
600 mm from the bottom edge of the heater has to be available under the heater.
When mounted directly under the ceiling, the distance from the ceiling has to be
50 mm at least.
If the water heater is mounted in enclosed areas, inter-ceilings, built-in structures and recesses,
ensure sufficient access to service fittings, electrical terminal boards, anodes and manholes.
Minimum spacing from manhole is 600 mm.
2.3 PLUMBING FIXTURE
The heater connects to water distribution tubes with G1/2“ thread in the bottom part of
the heater. Blue - cold water supply, red - hot water outlet. For potential disconnection of
the heater, the service water inlets and outlets must be provided with screw coupling Js 1/2“.
The safety valve is mounted on the cold water inlet identified with a blue ring.
The heater must be equipped with a membrane, spring-loaded safety valve. Safety valves with
fixed pressure settings from the manufacturer are used for the assembly. Each individually
lockable heater must be fitted with a cap on the cold water inlet, a test valve or a stopper
to check the operation of the check valve, with a check valve and a relief valve (Figure 6).
The safety valve with a check valve is supplied with the heater.

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It is necessary to check the safety valve each time before putting it into operation. It is checked
by manual moving of the membrane from the seat, turning the make-and-break device button
always in the direction of the arrow. After being turned, the button must click back into a notch.
Proper function of the make-and-break device results in water draining through the safety valve
outlet pipe. In common operation, such a check needs to be implemented at least once a month,
and after each heater shutdown for more than 5 days. Water may be dripping off the drain pipe
of the safety valve; the pipe must be open into the air, pointed down; environment
temperatures must not drop below zero.
Find necessary pressure values in the below. (Table 4)
Heaters must be provided with a discharge valve mounted on the cold service water inlet to the heater
for potential disassembly or repair. When assembling the security equipment, follow the standard.
Table 4
Figure 6
Figure 7
SAFETY VALVE
START-UP
PRESSURE
[MPa]
ALLOWABLE
OPERATING
OVERPRESSURE
OF WATER
HEATER [MPa]
MAXIMUM
PRESSURE IN
COLD WATER
PIPES [MPa]
0.6 0.6 up to 0.48
0.7 0.7 up to 0.56
11up to 0.8

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2.4 ELECTRICAL INSTALLATION
2.4.1 GENERAL INFORMATION FOR ELECTRICAL INSTALLATION
Perform the connection according to the scheme. Factory connection must not be changed! (Figure 9).
In the electric wiring casing remove the partition corresponding with the input wire diameter Ø8 or Ø10
(Figure 8). The degree of protection of electric parts of the heater is IP 44. Power input of electric element
is 4,000 W.
Figure 8
It is necessary to observe the below requirements during the electric wiring.
•The electric wiring scheme is attached to the water heater on the side of the electric
installation guard (Figure 9)
•Connection, repairs, and wiring inspections may only be implemented by a company
(person) authorised to such activity.
•Expert connection must be confirmed on the warranty certificate.
•Heater is connected to 3 PE-N ~400V/50 Hz power supply via a fixed movable wire.
The circuit must contain a breaker disconnecting all poles of the network, and a circuit
breaker (protector).
•Installations in bathrooms, laundry rooms, rest rooms and showers, must be in compliance
with standard.
•The degree of protection of electric parts of the heater is IP 44.
•Adhere to the protection against electric shock injury according to standard.
Figure 9
Ø10
Ø8
Ø8
Ø10

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2.5 OPERATING ACTIVITY
After the heater is connected to electric network, the heating element starts heating water. The element
is turned on and off by a thermostat. After reaching the temperature set, the thermostat switches off
the electric circuit and discontinues water heating. The control light signals if the element is in operation
(light is on) or if it is off (the light goes out). In case of longer operation without using the heated volume,
the thermostat has to be set to position 5°C to 8°C (set the “snowflake” symbol on the thermostat selector)
to avoid its freezing, or electricity supply to the heater has to be switched off.
2.6 FIRST COMMISSIONING
Before opening the power supply, the tank must be filled with water. The process of first heating
must be executed by licensed professional who has to check it. Both the hot water outlet pipe
and safety armature parts may be hot.
During the heating process the pressurised connection water that increases its volume due
to heating must drip off the safety valve. In non-pressurised connection water drips off
the overflow combination faucet. When heating is finished, the set temperature and the actual
temperature of consumed water should be roughly equal. After connecting the heater
to the water main and electrical power system, and after checking the safety valve (following
the instructions attached to the valve), the heater can be put into operation.
Before fist putting into service or after a longer shutdown the appliance has to be rinsed out
and flushed yet before heating is activated. Before heating starts, the tank must be completely
filled with water and the system properly flushed and vented. First heating of the tank has
to be watched.
Procedure of putting the heater into operation:
1. Check the water main and wiring. Check proper placement of operating and safety thermostat
sensors. The sensors must be inserted all the way in; first the operating and then the safety
thermostat.
2. Open the hot water valve on the combination faucet.
3. Open the cold water inlet valve to the heater.
4. As soon as the water starts running through the hot water valve, the heater is filled and the valve
can be closed.
5. In case of leakage (of flange lid), we recommend that the flange lid bolts are fastened.
6. Screw down the electric installation guard.
7. When hot service water is heated by electric energy, switch on the power supply.
8. When commencing operation, flush the heater until the cloudiness in the water is gone.
9. Make sure to fill in properly the warranty certificate.

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2.7 PUTTING OUT OF SERVICE, DISCHARGE
If the hot water heater is put out of service for a longer time, or if it is not going to be used
it has to be drained and disconnected from the electric supply network on all poles. The switch
for the supply lead or the fuse cut-outs have to be shut off.
At places with permanent risk of frost the hot water heater must be drained before the cold
season starts if the appliance remains out of service for several days and if the power supply
is disconnected.
Drainage of service water shall be performed after closing the shut-off valve in the cold water
supply piping (through the discharge valve for safety valve combination), and with simultaneous
opening of all hot water valves of connected fittings (water can be also drained through safety
valve; for that purpose, the safety valve is turned to the "Check" position). Hot water may
outflow during the drainage! If there is a risk of frost it has to be considered that not only
the water in the hot water heater and in the hot water piping may get frozen but also the water
in the entire cold water supply piping. It is therefore advisable to drain all fittings and piping that
carry water, up to the part where the house water meter is installed (connection of the house
to water main) which is not jeopardised by frost. When the tank is to be used again, it has to be
filled with water and one needs to make sure that the water flowing out at the hot water valves
did not contain any bubbles.
2.8 INSPECTION, MAINTENANCE & CARE FOR THE APPLIANCE
During the heating process the water that increases its volume during the heating must visibly
drip off the safety valve outlet (in non-pressurised connection this water drips off
the combination faucet valve). In full heating (about 74°C) the volumetric water gain is approx.
3.5 % of the tank capacity. The function of the safety valve has to be checked regularly.
If the safety valve control knob is lifted or turned to the “Control” position, the water must flow
out easily, without any obstacles, from the safety valve element to the outfall line. In common
operation, such a check needs to be implemented at least once a month, and after each heater
shutdown for more than 5 days.
Attention! In doing so, the cold water supply pipe and the connection fitting of the tank may get
heated! If the hot water heater does not work, or if hot water is not withdrawn, no water shall
drip off the safety valve. If water drips, then the water pressure in the supply piping is either too
high (if higher than 5.5 bars, a pressure control valve has to be fitted), or the safety valve
is defective. Please call a specialised plumber immediately!

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If water contains too many minerals, an expert has to come to remove the scale that forms inside
the tank, as well as free sediments. This has to be performed after one or two years of operation.
The cleaning is carried out through the hole in the flange - dismantle the flange lid and clean
the tank. A new sealing has to be used for re-fitting. Since the inside of the heater has special
enamel, which must not get in contact with the scale removing agent - do not work with a lime
pump. Remove the lime layer with a timber and suck it off, or wipe it off with a clout. After that,
the appliance must be rinsed thoroughly and the heating process is checked the same as during
the initial putting in operation. Do not use any abrasive cleaning agents (such as liquid sand,
chemicals - acid, alkaline) or dye thinners (such as cellulose thinner, trichlor, and the like)
to clean the outer shell of the heater. For cleaning use a wet clout and add a few drops of liquid
cleaning agent for household applications. Repeated heating causes lime scale settling
on the receptacle walls and mostly on the lid of the flange. Lime scale settling depends
on hardness of heated water, its temperature and on the volume of hot water used.
We recommend checking and cleaning the tank from scale and eventual replacement of the
anode rod after two years of operation. The anode life is theoretically calculated for two years
of operation; however, it changes with water hardness and chemical composition in the place
of use. Based on such an inspection, the next term of anode rod exchange may be determined.
If the anode is only blocked with sediments clean its surface and, if used up, mount a new one.
Have a company in charge of service affairs deal with the cleaning and exchanging of the anode.
When draining water from the heater, the combination faucet valve for hot water must be open,
preventing occurrence of under-pressure in the heater tank which would stop the water
from draining.
2.9 MOST FREQUENT FUNCTION FAILURES AND THEIR CAUSES
Table 5
FAILURE SYMPTOM INDICATOR SOLUTION
Water is cold •Light on
•The temperature set on the
thermostat is too low; heating
element failure
Water is cold •Light off
•No supply voltage!
•Thermostat failure
•Safety thermostat shut off
probably due to failed
operation thermostat
Water is not warm enough •Light on •Failure of one of the coils
in the element (3x 1350 W)
Temperature of water is
not corresponding with
the temperature set on
the control
•Defective thermostat
Water is constantly
dripping off the safety
valve
•Light off •high input pressure
•defective safety valve

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Do not attempt to repair the failure yourselves. Seek either expert or service help. It does not
take much for an expert to remove the defect. When making a repair appointment, report
the type and serial number you find on the performance plate of your water heater.
3OPERATION OF THERMOSTAT
3.1 SERVICING
Electrical installation cover for heaters OKCE 200
Figure 10
Electrical installation covers for heaters OKCE 80, OKCE 100, OKCE 125, OKCE 160
OKHE 80, OKHE 100, OKHE 125, OKHE 160
Figure 11
Tipping plastic guard
Electric circuit closing indicator lamp
Thermostat knob
Thermostat knob
Electric circuit closing indicator lamp

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Thermostat and no other part of the control panel is not a bearing part which can be used
for any handling with the heater.
3.1.1 TEMPERATURE SETTING
Water temperature is set by turning the thermostat knob. The desired symbol is adjusted against the fixed
point on the control panel (Figure 12, Figure 13).
Figure 12
Figure 13
Adjusting the thermostat knob to the left backstop does not mean permanent shutoff of
the heating element. When the heater is in use without blocking the daily rate, we do not
recommend the temperature to be set above 60°C. Select the "ECO" or "OPTIMUM" symbol
as the maximum.
Lower limit of temp. scope
(around 5°C)
Fixed point on the control
panel
"Anti-freezing" temperature
(about 8°C)
Upper temperature range
limit (about 74°C)
"Ideal" temperature
(about 60°C)
Fixed mark on the
control panel
Upper temperature range
limit (about 80°C)
"Ideal" temperature
(about 60°C)
Lower limit of temp. scope
(around 5°C)
"Anti-freezing" temperature
(about 8°C)

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4IMPORTANT NOTICES
4.1 INSTALLATION REGULATIONS
-Without a confirmation of performed electrical installation issued by an authorised company,
the warranty certificate shall be void.
-Check and exchange the Mg anode regularly.
-You have to apply for approval of a local power supplier to connect the heater.
-No stop valves can be put between the heater and the safety valve.
-If the overpressure in the water main exceeds 0.48 MPa, a pressure control valve must be mounted
before the safety valve.
-All hot water outputs must have a combination faucet.
-Before filling the heater with water for the first time, it is recommended to fasten the flange
connection nuts of the tank.
-It is not allowed to handle the thermostat, aside from temperature resetting with a control button.
-All electric installation handling, adjustment and replacement of the regulation elements shall only
be performed by an authorised service company.
-The thermal fuse must not be turned off! In case of thermostat defect, the thermal fuse interrupts
electric power input to the heating element if the water temperature in the heater exceeds 90 °C.
-If you don't use the heater (hot water tank) for longer than 24 hours, or if the facility with heater is
unattended, close the cold water inlet to the heater.
-The heater (hot water tank) shall be used exclusively in accordance with the conditions specified
on the performance plate and in the instructions for electric wiring.
-The recommended operating pressure in the hot water circuit is 0.4 MPa. At the hot water discharge
we recommend that a reverse flap and an expansion tank are installed (at least 4% of hot water
volume in the manifold) to eliminate reverse pressure shocks.
Both the electric and water installation must follow and meet the requirements
and regulations relevant in the country of use!
4.2 TRANSPORT & STORAGE INSTRUCTIONS
The device shall be transported and stored in dry place and protected from weather effects with temperature
range from -15 to +50°C. During loading and unloading the instructions stated on the packaging shall be
observed.

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4.3 DISPOSAL OF PACKAGING MATERIAL AND NON-FUNCTIONING
PRODUCT
A service fee for providing return and recovery of packaging material has been
paid for the packaging in which the product was delivered. The service fee was
paid pursuant to Act No 477/2001 Coll., as amended, at EKO-KOM a.s. The client
number of the company is F06020274. Take the water boiler packages to a waste
disposal place determined by the town. When the operation terminates,
disassemble and transport the discarded and unserviceable heater to a waste
recycling centre (collecting yard), or contact the manufacturer.
5PRODUCT ACCESSORIES
The product is supplied together with a safety valve and a thermometer. The above parts are packed
and placed in the packaging in the top part of the heater.
It is in your own interest to check the completeness of the accessories.
2-10-2018