Harvia K15G User manual

20032023 / Y05-0937 B
K10G, K12G, K15G
Instructions for Installation and Use of Electric Sauna Heater
EN
K10G, K12G, K15G

EN
Purpose of the electric heater:
The KG-heaters are designed for the heating of large
saunas to bathing temperature. It is forbidden to use
the heater for any other purposes.
• The guarantee period for heaters and control
equipment used in saunas by families is two (2)
years.
• The guarantee period for heaters and control
equipment used in saunas by building residents
is one (1) year.
• The guarantee period for heaters and control
equipment used in saunas by institutions is three
(3) months.
Please read the user’s instructions carefully before
using the heater.
NOTE!
These instructions for installation and use are intended
for the owner or the person in charge of the sauna,
as well as for the electrician in charge of the electrical
installation of the heater.
After completing the installation, the person in charge
of the installation should give these instructions to the
owner of the sauna or to the person in charge of its
operation.
Congratulations on your choice!
CONTENTS
1. INSTRUCTIONS FOR USE...........................................3
1.1. Piling of the Sauna Stones..................................3
1.2. Heating of the Sauna .........................................3
1.3. Control Unit of Heater........................................3
1.4. Throwing Water on Heated Stones ......................3
1.4.1. Sauna Water ...........................................4
1.4.2. Temperature and Humidity of the Sauna Room..4
1.5. Instructions for Bathing .....................................4
1.6. Warnings .........................................................4
1.6.1. Symbols descriptions.................................4
1.7. Troubleshooting ................................................4
2. THE SAUNA ROOM ...................................................5
2.1. Insulation and Wall Materials of
the Sauna Room ...............................................5
2.1.1. Blackening of the sauna walls.....................5
2.2. Sauna Room Floor .............................................5
2.3. Heater Output...................................................5
2.4. Ventilation of the Sauna Room............................5
2.5. Hygienic Conditions of the Sauna Room ...............6
3. INSTRUCTIONS FOR INSTALLATION ...........................6
3.1. Prior to Installation ............................................6
3.2. Fixing heater to Floor.........................................6
3.3. Safety Railing ...................................................6
3.4. Installation of Control Unit and Sensor .................6
3.5. Electrical Connections........................................6
3.6. Electric heater insulation resistance .....................7
4. SPARE PARTS ..........................................................8

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3
1.1. Piling of the Sauna Stones
The sauna stones for an electric heater should be
5–10 cm in diameter. The heater stones should be
solid blocks of stone specially intended for use in
the heater. Neither light, porous ceramic “stones“ of
the same size nor soft potstones should be used in
the heater, because they may cause the resistance
temperature to rise too high as a result of which the
resistance may be broken.
Stone dust should be washed off before piling the
stones. The stones should be piled into the stone
compartment over the grating, between the heating
elements (resistances) so that the stones support
each other. The weight of the stones should not lie
on the heating elements.
The stones should not be piled too tightly, so that
air can flow through the heater. See fig. 1. The
stones should be fitted loosely, and not wedged
between the heating elements. Very small stones
should not be put into the heater at all.
The stones should completely cover the heating
elements. However, they should not form a high pile
on the elements.
The stones disintegrate with use. Therefore, they
should be rearranged at least once a year or even
more often if the sauna is in frequent use. At the
same time, any pieces of stones should be removed
from the bottom of the heater, and disintegrated
stones should be replaced with new ones.
The guarantee does not cover any faults caused
by the use of stones not recommended by the plant.
Neither does the guarantee cover any faults caused
by disintegrated or too small stones blocking the
heater ventilation.
No such objects or devices should be placed inside
the heater stone space or near the heater that could
change the amount or direction of the air flowing
through the heater, thus causing the resistance
temperature to rise too high, which may set the
wall surfaces on fire!
1.2. Heating of the Sauna
Before you switch the heater on check always that
there aren’t any things over the heater or in the near
distance of the heater. See item 1.6. “Warnings”.
When the heater is switched on for the first
time, both the heater and the stones emit smell.
To remove the smell, the sauna room needs to be
efficiently ventilated.
The purpose of the heater is to raise the
temperature of the sauna room and the sauna stones
to the required bathing temperature. If the heater
output is suitable for the sauna room, it will take
about an hour for a properly insulated sauna to
reach that temperature. See item 2.1., ”Insulation
and wall materials of the Sauna Room”. A suitable
temperature for the sauna room is about + 65 °C
– +80 °C.
The sauna stones normally reach the required
bathing temperature at the same time as the sauna
room. If the heater capacity is too big, the air
in the sauna will heat very quickly, whereas the
temperature of the stones may remain insufficient;
consequently, the water thrown on the stones
will run through. On the other hand, if the heater
capacity is too low for the sauna room, the room will
heat slowly and, by throwing water on the stones,
the bather may try to raise the temperature of the
sauna. However, the water will only cool down the
stones quickly, and after a while the sauna will not
be warm enough and the heater will not be able to
provide enough heat.
In order to make bathing enjoyable, the heater
capacity should be carefully chosen to suit the size of
the sauna room. See item 2.3. ”Heater Output”.
1.3. Control Unit of Heater
The KG model heaters require a separate control unit
to operate the heater. The control unit should be
located outside the sauna room in a dry place, at an
altitude of approximately 170 cm. The temperature
sensor, by means of which the set temperature is
maintained in the sauna room, should be connected
to the control unit. The temperature sensor and the
overheating limiter are located in the sensor box
installed above the heater. The sensor box should
be installed in accordance with the installation
instructions of the control unit model in question.
The KG model heaters can be controlled with the
following control units:
• CX45J
See the instructions for use of the selected control
unit model.
1.4. Throwing Water on Heated Stones
The air in the sauna room becomes dry when
warmed up. Therefore, it is necessary to throw
water on the heated stones to reach a suitable level
of humidity in the sauna.
The humidity of the air in the sauna room is
controlled by the amount of water thrown on the
stones. A correct level of humidity makes the
bather’s skin sweat and makes breathing easy. By
throwing water on the stones with a small ladle, the
bather should feel the effect of air humidity on his
skin. Both too high a temperature and air humidity
will give an unpleasant feeling.
1. INSTRUCTIONS FOR USE
Figure 1. Piling of the sauna stones

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Staying in the hot sauna for long periods of time
makes the body temperature rise, which may be
dangerous.
The maximum volume of the ladle is 0.2 litres.
The amount of water thrown on the stones at a time
should not exceed 0.2 l, because if an excessive
amount of water is poured on the stones, only part
of it will evaporate and the rest may splash as boiling
hot water on the bathers.
Never throw water on the stones when there are
people near the heater, because hot steam may
burn their skin.
1.4.1. Sauna Water
The water to be thrown on the heated stones should
meet the requirements of clean household water.
The factors essentially affecting the quality of water
include the following:
• humuos content (colour, taste, precipitates);
recommended content less than 12 mg/l.
• iron content (colour, smell, taste, precipitates);
recommended content less than 0.2 mg/l.
• hardness – the most important substances are
manganese (Mn) and calcium (Ca);
• recommended content of manganese 0.05 mg/l,
calcium less than 100 mg/l.
Calcareous water leaves a white, sticky layer
on the stones and metal surfaces of the heater.
Calcification of the stones deteriorates the heating
properties.
Ferrous water leaves a rusty layer on the surface
of the heater and elements, and causes corrosion.
The use of humous, chlorinated water and
seawater is forbidden.
Only special perfumes designed for sauna water
may be used. Follow the instructions given on the
package.
1.4.2. Temperature and Humidity of the Sauna
Room
Both thermometers and hygrometers suitable
for use in a sauna are available. As the effect of
steam on people varies, it is impossible to give an
exact, universally applicable bathing temperature or
percentage of moisture. The bather’s own comfort
is the best guide.
The sauna room should be equipped with proper
ventilation to guarantee that the air is rich in oxygen
and easy to breathe. See item 2.4., ”Ventilation of
the Sauna Room”.
Bathing in a sauna is considered a refreshing
experience and good for the health. Bathing cleans
and warms your body, relaxes the muscles, soothes
and alleviates oppression. As a quiet place, the
sauna offers the opportunity to meditate.
1.5. Instructions for Bathing
• Begin by washing yourself; for example, by
taking a shower.
• Stay in the sauna for as long as you feel
comfortable.
• According to established sauna conventions,
you must not disturb other bathers by speaking
in a loud voice.
• Do not force other bathers from the sauna by
throwing excessive amounts of water on the
stones.
• Forget all your troubles and relax.
• Cool your skin down as necessary.
• If you are in good health, you can have a swim
if a swimming place or pool is available.
• Wash yourself properly after bathing. Have
a drink of fresh water or a soft drink to bring
your fluid balance back to normal.
• Rest for a while and let your pulse go back to
normal before dressing.
1.6. Warnings
• Sea air and a humid climate may corrode the
metal surfaces of the heater.
• Do not hang clothes to dry in the sauna, as this
may cause a risk of fire. Excessive moisture
content may also cause damage to the
electrical equipment.
• Keep away from the heater when it is hot. The
stones and outer surface of the heater may
burn your skin.
• Do not throw too much water on the stones.
The evaporating water is boiling hot.
• Do not let young, handicapped or ill people
bathe in the sauna on their own.
• Consult your doctor about any health-related
limitations to bathing.
• Parents should keep children away from the
hot heater.
• Consult your child welfare clinic about taking
little babies to the sauna.
- age?
- temperature of the sauna?
- time spent in the warm sauna?
• Be very careful when moving in the sauna, as
the platform and floors may be slippery.
• Never go to a hot sauna if you have taken
alcohol, strong medicines or narcotics.
1.6.1. Symbols descriptions
Read operators manual.
Do not cover.
1.7. Troubleshooting
If the heater does not heat, check the following
points:
• the current from the control centre to the
heater has been switched on
• the thermostat shows a higher figure than the
temperature of the sauna.
• the fuses to the heater are in good condition.

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2.1. Insulation and Wall Materials of the
Sauna Room
In an electrically heated sauna, all the massive wall
surfaces which store plenty of heat (such as bricks,
glass blocks, plaster etc.), must be sufficiently
insulated in order to keep the heater output at a
reasonably low level.
A wall and ceiling construction can be considered
to have efficient thermal insulation if:
• the thickness of carefully fitted insulating wool
inside the house is 100 mm (minimum 50 mm).
• the moisture protection consists of e.g.
aluminium paper with tightly taped edges. The
paper must be fitted so that the glossy side is
towards the inside of the sauna.
• there is a 10 mm vent gap between the
moisture protection and panel boards
(recommendation).
• the inside is covered by 12–16 mm thick
panelling.
• there is a vent gap of a few millimetres at the
top of the wall covering at the edge of the
ceiling panelling.
When aiming at a reasonable heater output, it may
be advisable to lower the ceiling of the sauna (normally
2100–2300 mm, minimum height 1900 mm). As a
result, the volume of the sauna is decreased, and a
smaller heater output may be sufficient. The ceiling
can be lowered so that the ceiling joists are fixed
at a suitable height. The spaces between the joists
are insulated (minimum insulation 100 mm) and
surfaced as described above.
Because heat goes upwards, a maximum distance
of 1100–1200 mm is recommended between the
bench and ceiling.
NOTE! Consult fire-extinguishing authorities to
find out which part of the fireproof wall may be
insulated.
NOTE! The protection of the walls or ceiling with
heat protection, such as mineral board fitted directly
on the wall or ceiling, may cause the temperature
of the wall and ceiling materials to rise dangerously
high.
2.1.1. Blackening of the sauna walls
Wooden material in a sauna, such as panels, blackens
with age. The blackening process is sped up by
sunlight and the heat from the heater. If the wall
surfaces have been processed with protective panel
agents, the blackening of the surface of the wall
above the heater can be seen quite quickly depending
on the protective agent used. The blackening is due
to the fact that the protective agents have less
resistance to heat than unprocessed wood do. This
has been proven in practical tests. The micronic
mineral aggregate that crumbles from the stones
on the stove may blacken the wall surface near the
heater.
When following the manufacturer’s approved
guidelines in the installation of the sauna heater,
the heater will not heat up enough to endanger the
flammable material in the sauna room. The maximum
temperature allowed in the wall and ceiling surfaces
of the sauna room is +140 degrees Celsius.
Sauna heaters equipped with CE signs meet all
of the regulations for sauna installations. Proper
authorities monitor that the regulations are being
followed.
2.2. Sauna Room Floor
Due to a large variation in temperature, the sauna
stones disintegrate in use.
Small pieces of stone are washed down on the
sauna room floor along with the water thrown
on the stones. Hot pieces of stone may damage
floor coverings installed underneath and near the
heater.
A light-coloured joint grout, used for a tiled floor,
may absorb impurities from the stones and water
(e.g. iron content).
To prevent aesthetic damage (due to the reasons
presented above) only dark joint grouts and floor
coverings made of rock materials should be used
underneat and near the heater.
2.3. Heater Output
When the walls and ceiling are covered with panels,
and the insulation behind the panels is sufficient
to prevent thermal flow into the wall materials,
the heater output is defined according to the cubic
volume of the sauna. See table 1.
If the sauna has visible uninsulated wall surfaces,
such as walls covered with brick, glass block, concrete
or tile, each square metre of said wall surface causes
the cubic volume of the sauna to increase by 1.2 m3.
The heater output is then selected according to the
values given in the table.
Because log walls are heated slowly, the cubic
volume of a log sauna should be multiplied by 1.5,
and the heater output should then be selected on
the basis of this information.
2.4. Ventilation of the Sauna Room
Sufficient ventilation is extremely important for the
sauna. The air in the sauna room should be changed
six times per hour. The air supply pipe should be
located at a minimum height of 500 mm above
the heater. The pipe diameter should be about 50–
100 mm.
The exhaust air of the sauna room should be taken
from as far from the heater as possible, but near the
floor level. The crosscut area of the exhaust air vent
should be twice that of the supply air pipe.
Exhaust air should be led directly into the air
chimney, or, by using an exhaust pipe starting near
the floor level, into a vent in the upper part of the
sauna. Exhaust air can also be led out through an
exhaust air vent in the washing room through a
100–150 mm opening under the sauna door.
For the above-mentioned system, mechanical ven-
tilation is necessary.
If the heater is mounted in a ready-made sauna,
the instructions of the sauna manufacturer should
2. THE SAUNA ROOM

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be followed when arranging ventilation.
The series of pictures shows examples of ventila-
tion systems for a sauna room. See fig. 2.
2.5. Hygienic Conditions of the Sauna Room
Good hygienic standards of the sauna room will
make bathing a pleasant experience.
The use of sauna seat towels is recommended to
prevent sweat from flowing onto the platforms. The
towels should be washed after each use. Separate
towels should be provided for guests.
Figure 2. Ventilation of the sauna room
1. Air supply vent placing area.
2. Exhaust air vent.
3. Possible drying valve, which is closed during heating and bathing.
The sauna can also be dried by leaving the door open after bathing.
4. If there is an exhaust vent in the washing room only, there should be a minimum
100 mm opening under the sauna room door. Mechanical ventilation is recommended.
Mechanical ventilation
2
44
2
1
1
min
500 mm
3 3
3.1. Prior to Installation
Prior to installing the heater, study the instructions
for installation, as well as checking the following
points:
• Is the output and type of the heater suitable for
the sauna room? The cubic volumes given in
table 1 should be followed.
• Is the supply voltage suitable for the heater?
• The location of the heater fulfils the minimum
requirements concerning safety distances given
in fig. 3 and table 1. It is absolutely necessary
to ensure that the installation is carried out
according to these values. Neglecting them can
cause a risk of fire.
• The heater should be installed so that the
warning texts on the cover of the junction box
can also be read without difficulty after the
installation.
• KG-heaters have not been approved to be
installed in a recess in the wall or floor.
3.2. Fixing heater to Floor
The heater is fixed to the floor at its two legs, at
the legs’ fixing points.
3. INSTRUCTIONS FOR INSTALLATION
Natural ventilation
Before fixing the heater, the minimum safety dis-
tances to inflammable materials should be taken into
consideration. See Table 1 and Figure 3.
3.3. Safety Railing
If a safety railing is built around the heater, the mini-
mum distances given in table 1 must be observed.
3.4. Installation of Control Unit and Sensor
Detailed instructions for the installation of both the
unit and the sensor are delivered with the control
unit.
3.5. Electrical Connections
The heater may only be connected to the electrical
network in accordance with the current regulations
by an authorised, professional electrician.
The heater is semi-stationarily connected to the
junction box on the sauna wall. The connection
cable must be of rubber cable type H07RN-F or its
equivalent.
It is advisable to vacuum or sweep the sauna room
floor regularly. In addition, the floor may be wiped
with a damp cloth.
The sauna room should be thoroughly washed at
least every six months. Brush the walls, platforms
and floor by using a scrubbing-brush and sauna
cleanser.
Wipe dust and dirt from the heater with a damp
cloth.

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Table 1. Installation details
Heater Output Saunaroom Min. distances Fuses [A]200 VAC
Cubic vol. Height A
min.
A
max.
B
min.
C
min.
D
min.
E
max. 3-Phase
kW
See item 2.3. See fig. 3.
min
m3
max
m3
min
mm mm mm mm mm mm mm
K10G 10,0 9 16 1900 70 170 50 70 1200 700 3x30
K12G 12,5 11 20 2100 100 200 50 100 1400 700 3x40
K15G 15,0 14 24 2100 100 200 50 100 1400 700 3x45
Model and
dimensions Width Depth Height Weight Stones max
K10G–K15G 505 mm 430 mm 700 mm 25 kg 60 kg
Figure 3. The heater’s safety distances. Note! If E is higher than E max, then B min. = C min.
NOTE! Due to thermal embrittlement, the use
of PVC-insulated wire as the connection cable of
the heater is forbidden. The junction box must be
splash-proof, and its maximum height from the floor
must not exceed 50 cm.
If the connection and installation cables are higher
than 100 cm from the floor in the sauna or inside
the sauna room walls, they must be able to endure
a minimum temperature of 170 °C when loaded
(for example, SSJ). Electrical equipment installed
higher than 100 cm from the sauna floor must be
approved for use in a temperature of 125 °C (mark-
ing T125).
The wiring diagrams are included in the control
unit’s installation instruction.
Further instructions concerning exceptional ins-
tallations can be obtained from local electrical au-
thorities.
3.6. Electric heater insulation resistance
When performing the final inspection of the electrical
installations, a “leakage” may be detected when
measuring the heater’s insulation resistance. The
reason for this is that the insulating material of the
heating resistors has absorbed moisture from the
air (storage/transport). After operating the heater
for a few times, the moisture will be removed from
the resistors.
Do not connect the power feed for the heater
through the RCD (residual current device)! Figure 4. The heater’s electrical connections

4. SPARE PARTS
HEATER HEATING ELEMENT OUTPUT PART NO.
K10G 1-6 1640W / 208V ZSS-120U
K12G 1-6 2050W / 208V ZSP-250I
K15G 1-6 3000W / 230V ZSP-255I
We recommend to use only the manufacturer’s spare parts.
21
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3
K10G, K12G, K15G
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T +43 (0) 7672/22 900-50 | F -80 | [e-mail] | www.sentiotec.com