Thermona THERM 90 KD.A Owner's manual

Manual for installation,
operation and maintenance
of boiler
Hanging gas condensing boiler
THERM 90 KD.A, 120 KD.A

THERM 90 KD.A, 120 KD.A
Manual for installation,
service and maintenance
of boiler

CONTENTS
1. General Information ..................................................................................4
1.1 Use ........................................................................................................4
1.2 Equipment Details .........................................................................................4
1.2.1 Equipment description..............................................................................4
1.2.2 Construction variants ...............................................................................4
1.2.3 General description .................................................................................5
1.2.4 Simplied hydraulic diagram and functional diagram (is not source material for assembly) ............6
1.3 Operational safety .........................................................................................6
1.4 Technical parameters ......................................................................................7
1.5 Set of boiler................................................................................................8
2. User manual ..........................................................................................9
2.1 Control and signalling......................................................................................9
2.1.1 Boiler control panel . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
2.1.2 LCD display ........................................................................................10
2.1.3 Information menu .................................................................................11
2.1.4 Error messages ....................................................................................12
2.2 Activation and deactivation of the boiler...................................................................12
2.2.1 Commissioning of the boiler .......................................................................12
2.2.2 Disconnection of the boiler from operation .........................................................13
2.3 Regulation................................................................................................13
2.3.1 Operation of the boiler without the room thermostat or regulator ...................................13
2.3.2 Operation of the boiler with spatial thermostat .....................................................13
2.3.3 Operation of the boiler using built-in equithermal regulation........................................14
2.3.4 Operation of the boiler using built-in equithermal regulation........................................16
2.3.5 Control of cascade boiler rooms ....................................................................16
2.3.6 Heating of utility water (DHW) .....................................................................16
2.4 Selected protective functions of the boiler .................................................................17
2.5 Maintenance and service..................................................................................18
2.5.1 Additionally lling the heating system..............................................................18
2.6 Warranty and warranty terms..............................................................................18
3. Installation Manual ..................................................................................19
3.1 Basic instructions for assembly of the boiler................................................................19
3.2 Complete character of the delivery ........................................................................19
3.3 Location of the boiler .....................................................................................20
3.4 Suspending the boiler.....................................................................................20
3.5 Connecting the boiler to the hot-water system.............................................................21
3.5.1 Dimensions and connection........................................................................21
3.5.2 Graphs of the connecting over-pressures of heating water (on the output for heating water) .........22
3.5.3 Expansion tank ....................................................................................22
3.5.4 Using anti-freeze mixtures .........................................................................23
3.5.5 Safety valve........................................................................................23
3.6 Connection of the boiler to the gas distribution ............................................................23
3.7 Filling and discharging of the heating system ..............................................................23
3.7.1 Procedure for lling the heating system: ............................................................23
3.7.2 Additional lling of water into the heating system ..................................................23
3.7.3 Discharging of water from the heating system ......................................................23
3.8 Condensate outlet ........................................................................................24
3.9 Design of gas exhaust.....................................................................................24
3.10 Connection of the boiler with the tank.....................................................................25
3.11 Connection of the boiler to electricity .....................................................................25
3.11.1 Connection of the room thermostat ................................................................25
3.11.2 Connection of aroom regulator with OpenTherm+ communication .................................26
3.12 Boiler installation options .................................................................................26
4. Additional information for service ....................................................................27
4.1 Gas tting EBM-PAPST GB 057 – setting ....................................................................27
4.2 Boiler combustion adjustment procedure..................................................................28
4.3 Electrical connection diagram .............................................................................29
5. Record of warranty and post-warranty repairs and annual controls......................................30
6. Production Information Sheet ........................................................................31
7. Certicate of Product Quality and Completeness .......................................................35
!
Graphic symbols
used in the text:
Notication of the producer directly related to the
operational safety of the consumer appliance
Information recommended
by the producer

4THERM 90 KD.A, 120 KD.A
1.1 Use
THERM 90 KD.A and120 KD.A hanging gas condensing boilers are modern gas appliances suitable for heating buildings with
aheat loss below 90 or 120 kW when used independently, or for larger buildings with ahigher heat loss when used in acascade.
The required boiler room output can be obtained by arranging boilers into acascade controlled by its own regulation,
including equithermal. This way, you can obtain aheat source with high eciency, smart operation and high reliability with
asimple installation. The boiler units are designed as appliances that use water steam condensation in the combustion process
and excel in high eciency with minimum emissions into the air. It means that their operation is economical and does not
strain the environment. The output of the boiler is continuously regulated within the scope of 27 – 100 % and it automatically
adjusts to the needs of the building. The installed top components by leading global producers guarantee ahigh technical
standard of the boiler.
!The minimum water pressure in the heating system must be maintained at 0.8 bar (measured in cold condition)
to ensure the proper function of the boiler. THERM 90 KD.A and 120 KD.A boilers are not equipped with an
expansion vessel with regard to their output and variability of use. If the boiler is connected to asystem with
an open expansion tank, it has to be installed at least 8 metres above the boiler.
1.2 Equipment Details
1.2.1 Equipment description
option to heat water – heating in indirect heating storage tank
natural gas operation
fully automated operation
low consumption of electricity
automatic uent output modulation
simple boiler control
high comfort level
built-in equithermal regulation
ability to control by the superior indoor thermostat or intelligent indoor control unit
high level of operational safety
security elements of the boiler prevent the boiler from overheating and gas escapes
built-in energy saving circulation pump
safety valve 4 bar
protective functions (anti-freeze protection, pump protection, etc.)
electric ignition (saving of fuel)
1.2.2 Construction variants
THERM 90 KD.A, 120 KD.A
closed combustion chamber
version designed only for heating (water can be heated in an external indirect heating reservoir)
air for combustion is sucked in from the open air
1. GENERAL INFORMATION

5
THERM 90 KD.A, 120 KD.A
1.2.3 General description
The THERM 90 KD.A and 120 KD.A gas boiler consists of asupport frame, on which all operating elements of the boiler
are attached. In the upper part of the boiler, the Sermeta compact stainless condensing body is installed; it combines the
combustion chamber with the burner and the stacked two-chamber stainless exchanger. The casing of the condensing body is
also stainless to guarantee ahigh thermal resistance and service life of the body. The heat transfer surfaces of the exchangers
consist of round tubes which must be protected from getting clogged by impurities from the heating system. Therefore, the
heating system must be tted with asuitable lter and sludge appliance at the input for the water returned into the boiler
(such as aSpiro valve). Temperature sensors are located on the input and output heating water collector on the body. The
removable front wall of the body is made of aluminium alloy and it is tted with two electrodes (ignition and ionizing), atube
burner and shaped piping for the supply of gas mixed with air.
The preparation of the gas and air mixture is provided by the compact set of premix fan, mixer and gas tting. The mixture
is made by the mixer in cooperation with aspecial gas tting. It consists of agas pressure regulator, two solenoid blocking
valves and ratio regulation of the output volume of gas with elements for mechanical setting. The parallel ratio regulation
can only be set by using special devices (combustion product analyser). The whole system operates so that the volume of
added gas is directly proportional to the volume of air through the mixer delivered with the ventilator. Therefore it can be
stated that the output on the boiler depends on the volume of the air ow for combustion.
As aresult, the revolutions of the ventilator are uently controlled within awide range which ensures the high output range
of the boiler. The air is supplied into the ventilator is through the shaped piping from the connection system.
The outow of condensate from the condensation body, exhaust piping for burnt gases and the supply of air are directed by
hoses into the odour closure (trap), from where the condensate ows outside the boiler.
The supply of combustion air, including the forced exhaust of burnt gases is, as arule, ensured by coaxial piping which runs
horizontally through the peripheral wall or vertically
through the roof construction into the open air. It is
necessary to install the piping to prevent (due to the
low temperatures of burnt gases) the possibility of
the freezing of the exhaust terminal. Vertical piping
must terminate at the roof chimney, horizontal with
aslight slope into the exhaust from the boiler.
The return water inlet is equipped with an energy-
ecient circulation Wilo pump ensuring water ow
through the boiler. The sucient ow and pressure of
heating water are monitored by aow and pressure
switch. The boiler is also tted with asafety valve
for over-pressure protection of the boiler. The boiler
may also be expanded with asuitable motorised
three-way valve to divide the functions of heating
hot water and the heating system.
The control panel is completely plastic. On the front
side, there are control elements. The HDIMS20-TH20
single panel automatics is built-in and it contains
electronic circuits for starting the burner and
microprocessor control of the boiler.

6THERM 90 KD.A, 120 KD.A
1.2.4 Simplied hydraulic diagram and functional diagram (is not source material for assembly)
THERM 90 KD.A, 120 KD.A
1 - Mixture preparation
2 - Safety valve
3 - Circulation pump
4 - Flow switch
5 - Condensing body
6 - Emergency thermostat
7 - Thermal probe
8 - Pressure switch
9 - De-aerating valve*
In the case of gas odour
close the gas valve under the boiler
ensure ventilation of the room (windows, door)
donot manipulate the electric switch
liquidate any naked ame
immediately call service (the boiler must not be used until after the service inspection)
In the case of an odour of combustion burnt gases
disconnect the boiler
ensure ventilation of the room (windows, door)
call service (the boiler must not be used until after the service inspection)
In the case of aconsumer appliance re
close the gas valve under the consumer appliance
disconnect the consumer appliance from the electricity network
liquidate the re with powder extinguishing equipment or afoam extinguisher
!THERM boilers are tted with all safety, emergency and protective elements to ensure completely safe boiler
operation. If irrespective of this, e.g. due to unprofessional intervention, irregular inspections and revisions of
the boiler, etc., there is anon-standard status then we recommend proceeding as follows:
1.3 Operational safety
1
2
3
4
5
6
7
8
7
9
HEATING WATER
OUTPUT
GAS
INPUT
HEATING WATER
INPUT
CONDENSATE
OUTPUT

7
THERM 90 KD.A, 120 KD.A
Technical description Unit THERM 90 KD.A THERM 120 KD.A
Fuel -natural gas natural gas
Construction - C13 , C33, C43, C53, C63, C83 B23 , C33, C43, C53, C63, C83
Consumer appliance category - I2H, I2E I2H, I2E
Annual energy consumption GJ 182 210
Nominal thermal input power kW 89.70 115.0 0
Minimum thermal input power kW 24.20 24.20
Nominal heat output at
Δt = 80/60 °C kW 88.70 111. 50
Δt = 50/30 °C kW 95.00 120.00
Minimal thermal output by Δt = 50/30 °C kW 25.60 25.70
Gas overpressure on the consumer appliance input mbar 20 20
Consumption of gas m3.h-1 2.57–9.52 2.45–12.03
Maximum overpressure of heating system bar 4.0 4.0
Minimum overpressure of heating system bar 0.8 0.8
Max. output temperature of heating water °C 80 80
Diameter of coaxial of exhaust for burnt gases mm 110/160 110/160
Average burnt gases temperature at rated output °C 75 80
Flue gas temperature in case of overheating °C 82 86
Lowest ue gas temperature at min. heating output °C 25 33
Weight ow of burnt gases g.s-1 11. 5 – 43 .0 10.7–54.1
Mass ow rate of burnt gases at minimum heating
output g.s-1 11. 5 10.7
Usable over-pressure of the ventilator Pa 195 195
Mass concentration of CO2%8.7–9.0 8.7–9.0
Acoustic performance level dB (A) 62 64
Boiler eciency %98–106 97–106
NOx class of boiler - 6 6
Type of electricity supply - ~ ~
Nominal supply voltage / frequency V/ Hz 230 / 50 230 / 50
Nominal current of the circuit breaker for consumer
appliance A 2 2
Auxiliary
electricity at
nominal heat input power W 288 355
partial loading W198 165
emergency status W 3 3
Level of coverage of electrical part - IP x1D IP x1D
Environment under CSN 332000-5-51 ed.3 - normal AA5 / AB5 normal AA5 / AB5
Dimensions of boiler: height / width / depth mm 970 / 530 / 425 970 / 530 / 500
Weight of boiler kg 68 85
1.4 Technical parameters

8THERM 90 KD.A, 120 KD.A
1.5 Set of boiler
THERM 90 KD.A, 120 KD.A
1 - Condensing chamber
2 - Ventilator
3 - Temperature sensor
of heating
4 - Mixer
5 - Emergency thermostat
6 - Circulation pump
7 - Gas valve
8 - Safety valve
9 - Control panel
10 - Pressure switch
2
5
8
3
6
9
1
4
7
10

9
THERM 90 KD.A, 120 KD.A
2.1 Control and signalling
2. USER MANUAL
The operating mode switch has the following positions
Switching o the boiler – the protective boiler functions remain active (when the boiler is connected to the mains and
the gas supply is open). If selecting this mode, the boiler display only indicates the pressure in the heating system, the
heating is disconnected, there is heating of DHW and, at the same time, the backlit display is OFF.
Summer regime (only heating of DHW is ON, the heating is OFF)
Winter regime (heating and heating of DHW is ON)
Unblocking the failure status of the boiler
Service mode (the function “sweeper“ – the output of the boiler can be uently regulated by the wheel – left position
= minimum output and temperature, right position = maximum output and temperature). This regime serves only for
service activity and measurement (emissions, temperatures of burnt gases, etc.)
Setting the heating temperature – rotary control knob for user setting of the output temperature of water in the
heating system within the range 30–80°C. In the case of selected equithermal regulation, the shift in the heating curve
is set by the control knob (within the range ± 15°C from the equithermal curve)
temperature of heating water (shift of equithermal curve)
manometer
displaySwitch for operating regimes multifunctional buttons
disconnection of water heating
!This appliance may be used by children at the age of 8 and above and by people with impaired physical, sensory
or mental abilities, or lack of experience and knowledge provided that they are supervised or that they have been
instructed on the safe use of the appliance, and that they understand the potential risks. Children must not play
with the appliance. Children must not perform cleaning and maintenance of the appliance without supervision.
2.1.1 Boiler control panel
The control elements of the boiler are under the front plastic cover. The cover is opened by lightly gripping the handle in the
upper part or by pressure on the lower part of the hole for the display.

10 THERM 90 KD.A, 120 KD.A
Multi-functional buttons – designated for the diagnostics and setting of he parameters of the boiler exclusively by
aservice technician or for switching o information data (see below)
Manometer – displays the measured water pressure in the heating system
Indication of set temperature
After turning the control knob for setting the temperature of the heating system or DHW (boilers with ow heating of DHW)
the respective symbol of the regime will start to ash along with the numeric display of the temperature on the LCD display.
In this case, the value of the last temperature set is indicated. After the termination of the setting, the indication of the set
temperature remains for about 5 seconds. The following permanent display of the numeric value and the symbol, the real
temperature of the respective regime is indicated again.
reset
2.1.2 LCD display
Setting the water temperature – not used, only active when using the machine to heat the solar accumulation reservoir.
The hot water temperature is set directly on the tank thermostat when the THERM 90 KD.A and 120 KD.A are connected
with astandard tank.
Disconnection of water heating – setting the rotary control knob for user setting of the output temperature of the
hot water to the left side position (less than 10° of the route); the heating of water can be in winter mode permanently
disconnected from operation.
option to disconnect the water heating
detail

11
THERM 90 KD.A, 120 KD.A
SYMBOL NAME MEANING
Display eld Display of temperatures, failure statuses and service values
Valve Permanent lighting – the boiler is in the water heating mode
Flashes – displays the hot water temperature or the requested water temperature
Radiator Permanent lighting – the boiler is in the heating mode
Flashing – shows heating temperature or required heating temperature
Flame Permanent light – the burner burns
Flashes – the burner burns during the service mode
Curve (“K“ factor) Permanent lighting – the equithermal heating regime is selected
Flashes – displays the “K“ factor, not usual with °C outside temperature
Frost ake The boiler is in "WINTER“ mode
Communication Permanent lighting – OpenTherm+ communication is active
Flashes – communication with the interface of the cascade is active
Description of symbols shown on the display
2.1.3 Information menu
Buttons and are used for entrance and bi-directional browsing in the information menu in the following
sequence order:
PARAMETER SHOWS ON THE DISPLAY
The required heating temperature
The temperature of heating
Requested temperature DHW (2)
Temperature DHW (2)
Outside temperature (1)
Equithermal curve (factor „K“)
Temperature of water returned
from the system
Ventilator speed four-digit value of revolutions per minute
Return to normal display
If button or is not pressed for 10 seconds, or if pressing buttons and at the same time, the information
menu is terminated.
(1) - an outdoor temperature display is only available in the case of the correction of the respective sensor and the selection
of equithermal regulation
(2) - when selecting heating of water in the external reservoir, display "- -" , (with additional heating of the solar accumulator,
the numeric value is displayed–see below)

12 THERM 90 KD.A, 120 KD.A
* The boiler is blocked. To reactivate the boiler, manually reset by switching the regime.
The error code is saved into the memory of the processor where it is also saved in the case of asupply failure. The service
technician can check the memory and ascertain the history of failure statuses.
ERROR CODE MEANING
E01 * Blocking of the activity when the burner is not ignited
E02 Insucient ow of heating value
E04 Defect in thermal heating probe (interruption of short-circuit)
E05 Defects in the water temperature probe (when connecting to the cascade, defect in system
temperature probe)
E06 * Blocking of the activity when the boiler is overheated (emergency thermostat, emergency
exchanger fuse)
E07 Defect to the outside temperature sensor
E08 Failure of ventilator (feedback signal for revolutions)
E09 Failure of ventilator (revolutions outside the regulation range)
E10 Failure of ventilator (rotate at STOP)
E12 Failure of insucient pressure of heating water after 4 pump cycles
E22 Low pressure of heating water
!
2.2 Activation and deactivation of the boiler
2.2.1 Commissioning of the boiler
The boiler must only be commissioned by aservice employee authorised by the producer! The list of service
technicians is attached to the product.
The procedure for the rst ignition of the boiler is as follows
set the rotary button of the input temperature of the heating water of the boiler to the maximum
insert the network supply into the socket and switch on the boiler with the switch for operating regimes
turn the operating mode switch into the right end position for ashort time to automatically ignite the boiler (provided
the gas supply is deaerated)
inspect the correct activity of all thermostats and control elements
inspect all functions of the boiler
adjust the burning of the machine or modify the setting according to demands of the area to be heated
train the user
Action to be taken before and during the activation of the boiler.
Before the rst activation of the boiler it is necessary to take the following measures
check that the heating system is lled with water and the boiler is correctly de-aerated
ensure that all valves under the boiler and in the heating system are open
open the gas valve and, using the gas escape detector or foam-making solution, test the tightness of the gas distribution
in the boiler
2.1.4 Error messages
Any error or other anomaly is indicated by ashing, abacklit LCD display, display of the error code and key symbol. On the
rst position of the display is symbol “E”; on the other positions is an error code with the meaning according to the table.
Error code displayed on LCD and the meaning:
!If the boiler exchange is not de-aerated, irreversible damage to the boiler may occur!

13
THERM 90 KD.A, 120 KD.A
2.2.2 Disconnection of the boiler from operation
It is possible to disconnect the boiler for ashorter period by the operating regime switch or by the switch on the room
thermostat.
For longer disconnection of the boiler outside the heating season (e.g. during summer and holidays) it is recommended
to close the gas valve. However, leave the boiler connected to the electricity network. Only in this case will the protective
functions of the boiler be active.
Any full disconnection of the boiler (closing of gas supply, disconnection from electricity network) must be done with respect
to the ambient temperature of the environment in the respective season! There is arisk of the heating system or DHW circuit
freezing due to damage to the boiler or other elements of the heating system.
2.3 Regulation
The boiler is tted with internal regulating elements at ahigh level for such basic equipment. The standard is integrated
equithermal regulation. The system can be heated in several dierent ways: regulation according to the room temperature
in the selected reference room, equithermal heating water regulation, combined regulation etc.
2.3.1 Operation of the boiler without the room thermostat or regulator
In this regime the boiler maintains the selected temperature of the heating water. The room thermostat or the regulator is
not connected; the terminals for connection must be mutually interconnected (set in production).
In this regime, set the temperature of the heating water directly on the control panel of the boiler with the middle button.
The operation of the independent boiler
(without selection of equithermal regu-
lation) is recommended to be controlled
using at least asimple room thermostat.
The room temperature is time stable
and keeps the boiler in the operating
regimes. It is recommended to use the
built-in equithermal regulation either
independently or completed by the
spatial regulation, as mentioned below.
The setting of output range of the boiler and other parameters must be in accordance with the technical data.
Any overloading and incorrect use of the boiler may cause the devaluation of its components Warranty does
not apply to such damaged components!
The boiler must not be operated with the emergency or ue thermostat or another safety component put out
of operation or replaced by other equipment than that stated by the producer! Otherwise, an accident or other
hazardous statuses may occur!
Aservice technician authorised by the producer must familiarize the user during activation with the operation of
the boiler, the individual parts, the safety elements and the manner of control, complete the Warranty Certicate
and give this user manual to the user.
The user is obliged to ensure of the correct use of the boiler in accordance with this manual which is aconditions
of acceptance of the warranty. In addition, it is strictly forbidden to intervene in any manner into the secured
parts in the boiler!
!
2.3.2 Operation of the boiler with spatial thermostat
In this manner of regulation, the boiler maintains the selected temperature of heating water. The room thermostat is
connected instead of the X9 terminal jumper in the boiler control automatics. The operation of the boiler is consequently
controlled according to the inside temperature in aroom where the room thermostat is located (the reference room). It is not
recommended to mount thermostatic valves on radiators in the reference room!
Thermona supplies and recommends aseries of room thermostats for boilers controlled by room temperature:
such as THERM Home S, THERM Home SR (wireless version), BT52 WiFi etc.

14 THERM 90 KD.A, 120 KD.A
!
The mentioned ad-in regulators are not (with the exception of special oers) included in the delivery of the boiler!
Description of the activity of the boiler in the mentioned regime:
The working phase of the boiler starts by switching on the room thermostat (the thermostat evaluated low temperature
compared with requested) at the moment when the regime control knob is in the winter regime position. The three-way
valve relay is disconnected (for boilers with water storage heating); the of circulating pump is activated, as well as the ignition
system and ventilator. Ignition of the boiler is for the adjusted starting output. It remains for 2 seconds after activation of the
boiler. The output is then decreased to the minimum with aslow linear start (about 50 s) to the modulation point stated by
service for setting the maximum heating output. The regulation of output of the boiler in this phase is by PID (proportional/
integral/derivative) with keeping the temperature set by the wheel on the control panel (within the range 30 – 80 °C). During
the whole time of heating, the regulation limit of the output temperature is checked. When heating the system with lower
input power than the minimum output of the machine, there is an increase of the output temperature of heating water by
3 °C above the adjusted temperature (for 30 seconds from ignition, this value is increased to 10 °C). In this stage, the boiler
interrupts burning while keeping the circulation pump running and starts atime limit for re-ignition (service setting from 0–10
minutes). In this manner the boiler becomes ahighly adaptable source of heat due to the high variability of the consequently
regulated heating sets (e.g. use of zone regulation, thermostatic valves, etc.).
After disconnection of the spatial thermostat or after switching the selection unit into the “WINTER“ mode, the burning of
the burners is stopped and the pump is ON for the set time (service setting within the range 0 – 10 min.). This function is
used for taking the heat from the condensing body and for improving the allocation of temperatures of bodies when using
thermostats with PI linkage with short working cycles.
In the case of the installation of the room thermostat eventually. and controller in the reference room, aminimum
of one radiator must be left without athermostat head. To increase thermal comfort, we recommend not to
mount thermostatic heads on radiators in the reference room at all.
2.3.3 Operation of the boiler using built-in equithermal regulation
This regime is accessible in the boiler in the standard variant but is not activated. The activation and the primary setting of
the regulation is performed at the request of the client by an authorized service technician.
During equithermal regulation the boiler changes the temperature of the heating water automatically according to the
changes in the outside temperature.
This manner of regulation can only be used with the connected outside temperature sensor. The outside sensor is located on
the coldest wall of the object (north or north-west) approximately 3 m above the ground. The sensor must not be inuenced
by any other thermal inuence such as open windows, sunlight, ventilation shafts, etc.
Description of the activity of the boiler in this regime:
The working phases of the boiler are identical with the previous regime with the dierence that the temperature for the
heating system is automatically set according to the outside temperature (ascertained by the sensor). The calculation of
the requested temperature of the heating system is the function of the ambient temperature and the function of the “K“
factor (declination of equithermal curve), which is set by the service technician with respect to the locality and nature of the
heating system. The user sets the required thermal comfort by the turning knob of the heating water temperature on the
control panel (correction of the equithermal curve shift within ± 15°C of heating water). The equithermal curve is modied
for standard heating systems with radiators.
In the case of failure of the ambient temperature sensor, this status is signalled by E07 failure and the boiler continues in
operation with the temperature of the heating system according to the setting in the previous regime (without equithermal
regulation).
Adjustment procedure:
When setting the equithermal regulation, it is necessary to distinguish the declination and the shift of the equithermal curve.
When setting the inclination of the equithermal curve, the following rule applies: change the curve inclination parameter
towards the higher values in case of bad thermal
insulation properties of the building (the curve
goes up); the parameter can be lowered when
good insulation is provided (the curve goes
down).
The declination of the curve is set by the
authorized technician in the service menu of
the automatic control system of the boiler!

15
THERM 90 KD.A, 120 KD.A
The calculated temperature of the heating water is
restricted to max. 80 °C. If the calculated temperature
varies within the range 20 ÷ 35 °C the requested
temperature is restricted to the minimum temperature
of the boiler, i.e. 30°C and the function of periodical
running of the boiler is activated within the xed interval
of 15 minutes and the variable time of running for 35 °C
according to the formula: Note:
Ton = interval of activation of the boiler
To = remaining interval for the disconnection
of the boiler into xed 15 minutes
Ton (min) = 15 – To ; which To (min)
= 35 – calculated equithermal temperature
If the calculated equithermal temperature is
≤ 20°C, the boiler remains o.
Example of the course of selected curves
during shift correction (middle turning knob)
It results from the mentioned facts that using the knob to set the temperature of the heating on the control panel, in this
regime, the requested temperature of the heating space is indirectly set. The default setting of the equithermal curve “K” =1.6.
The initial user setting of the rotary control knob is in the middle of the setting route (the indicator is up which corresponds to
the shift of the curve 0 °C). After inspection of the temperature of the heated space (after approximately 24 hours), it is possible
to perform additional setting according to all requirements for thermal comfort. Due to the inuence of the equithermal
regulation the change of ambient temperatures will be compensated and the level of temperature of the heated space will
be automatically kept at aconstant level.
Using this regime of regulation, afurther decrease of operating costs can be achieved while improving thermal comfort
(continuous heating of heating bodies). Finally,
this option can be appreciated as pre-regulation
of the primary heating circuit when using zone
regulation (by mixing valves), etc.
Graph of the course of equithermal
curves (zero shift)
!During the activated equithermal regulation the meaning of the function of the middle button on the control
panel of the boiler is changed. In this case, the mentioned knob is used to set the shift of the heating curve
(within the range ±15 °C from the equithermal curve set by the service technician).
K=0,5
K=1,0
K=1,5
K=2,0
K=3,0
K=4,0
K=6,0
20.00
30.00
40.00
50.00
60.00
70.00
80.00
-25-20-15-10-505101520
Outdoor temperature (°C)
Heating water temperature (°C)
K=1,0
K=3,0
+15°C
-15°C
+15°C
-15°C
20.00
30.00
40.00
50.00
60.00
70.00
80.00
-25-20-15-10-505101520
Outdoor temperature (°C)
Heating water temperature (°C)

16 THERM 90 KD.A, 120 KD.A
2.3.4 Operation of the boiler using built-in equithermal regulation
To provide ‘full’ equithermal regulation (including the settings of time programs etc.), we recommend using the intelligent
programmable regulator PT59X, PT59 or CR 04, which periodically communicates with the boiler automatic microprocessor.
There is the transfer of information not only about the required temperature of the heating system depending on the
spatial and outside temperature, but also the display of operating information about the boiler (work regime, performance,
temperatures, possible failures, etc.). This system is characterized by many adjustable and displayed parameters for optimal
control of the heating equipment with modulation of the boiler output.
The mentioned ad-in regulators are not (with the exception of short-term special oers) included in the delivery
of the boiler!
2.3.6 Heating of utility water (DHW)
As astandard, the THERM 90 KD.A and 120 KD.A boilers are modied for heating water in an external indirect heating tank.
Athree-way valve must be installed for this purpose.
Reservoir heating of water – DESCRIPTION OF ACTIVITY
If the thermostat of the hot water storage tank is ON, the working phase of heating of the storage tank starts. The three-way
valve relay is switched on and if the boiler was running in the phase for heating the heating system, the burner and pumps
are stopped.
The pump starts when the three-way valve is readjusted (according to the settings in the interval of 8 or 120 seconds). After
the sequence for the inspection of security elements, the ignition of the burner is enabled.
From detecting the presence of the ame, the starting output of the boiler is kept for 2 seconds and then there is the phase
of uent modulation of the output with PID regulation with the stated value of the temperature of heating of 80 °C. During
the whole time of heating, the limits of the regulation of the output temperature are checked. In the case of any increase
above 86 °C the burning is stopped and circulating pump remains active. The reignition is in the case of adecrease of the
temperature under 80 °C. The working phase of the water heating terminates with the disconnection of the thermostat of
the hot water storage tank.
This is followed by stopping the burning and then there is the additional cooling of the exchanger with the time function
for the running of the circulating pump (10 seconds). After termination and stopping of the pump, there is switching of the
three-way valve and resetting is activated. The three-way valve readjustment interval is set using the function for blocking
the boiler activity for 8 or 120 seconds. Only then, can the requested heating of the heating system be run.
In the case of parallel requests, the water heating regime takes priority over the heating of the heating system.
2.3.5 Control of cascade boiler rooms
The THERM 90 KD.A and 120 KD.A hanging boilers can be connected in acascade. It is already well known and time-tested
principle of boilers, both from the hydraulic and the control point of view. The boiler cascade can be conveniently controlled
by our regulation communication system that provides permanent communication between the individual boilers. For this
purpose, Thermona delivers cascade regulators, TKR or TKRC, which follow the earlier used interfaces of IU 05 andIU 04.10.
For more information about the principle, design, type of cascade boiler rooms control etc. are available, for
example on the website www.thermona.cz.

17
THERM 90 KD.A, 120 KD.A
2.4 Selected protective functions of the boiler
Anti-blocking functions
After 24 hours of inactivity, the pump runs for 30 seconds to prevent any blocking. After 24 hours of inactivity. the three-way
valve relay is activated for 10 seconds (if the boiler is tted with it) due to the same reason. In the case of arequest for heating
(heating or hot water) during the execution of this function, the anti-blocking function is automatically terminated and the
request runs. The anti-blocking function is also active when blocking the activity of the boiler in the position of the driver in
the mode “OFF“ (if the boiler is still connected to the electricity network).
Anti-freeze protection
The boiler is tted with an anti-freeze protection system which protects the boiler (not the heating system, storage tank and
hot water distribution lines) against freezing. Anti-freeze protection is activated in the case of adecrease of the temperature
in the boiler under 6 °C. The pump is activated, the boiler is ignited and heats the heating circuit with aminimum output
of 30 °C. The burning is stopped at this temperature and the pump continues running during the function for running the
pump. If the boiler is in the status for blocking burning (failure), only the pump is activated. The anti-freeze function is also
active with the selector in the position of the control knob in the position “OFF“ or in “SUMMER REGIME“.
!
!
Only an authorised service technician can change the anti-cycling time within the range from 0 to 10 minutes!
Run-out of the pump
The run out of the pump is set in production for 5 minutes. After the extinction of the burner caused by the disconnection of
the room thermostat, the pump continues to operate during the adjusted run out of the pump. In the case that in the winter
regime the boiler is operated without the room thermostat, the pump continues to be ON.
Only an authorised service technician can change the run out of the pump during operation with the room
thermostat within the range from 0 to 10 minutes.
Notication: All the above-mentioned security and registered functions are in activity only if the boiler is
connected to the electricity!
With respect to the request for increased checking of the microprocessor once every 24 hours of operation,
the forced reset of electronic system is performed with the consequent initialization (it is reected by short-
term interruption of the boiler and deactivation of data on the display similarly as during the activation of the
network inlet of the boiler into the socket).
Anti-cycling
The function that prevents the cycling of the boiler in the heating regime when in the case of operating disconnection of
the boiler, re-ignition of the boiler is not permitted before expiration of the adjusted, anti-cycling time (5 minutes are set in
the production). This function is mostly used in such heating systems where the maximum thermal loss of the stated object
corresponds to the lowest limit of the power range of the boiler.
Flow check (pump operation check)
Before each ignition of the boiler there is acheck of the ow switch, which evaluates the correct function of the boiler pump.
Rechecking the ow switch is activated if within 15 seconds of running the pump, the ow sensors is not activated. The
pump is stopped and after 15 seconds there is the next attempt to activate the boiler. This phenomenon is repeated 4x with
consequent signalling of the failure E12. It is necessary to de-block the failure by the regime switch. If the time of inactivity
of the pump before rerunning the boiler exceeds 30 minutes, the rst interval for running the pump is prolonged to 180
seconds. For restoration of the activity of the boiler it is necessary to disconnect and connect using the rotary control knob
for selection of regimes or by disconnecting and connecting the network supply.
!
Run-out of the ventilator
After termination of burning, the ventilator is in operation for 30 seconds while keeping the revolutions corresponding to the
starting output (taking the remaining of burnt gases from the combustion chamber).

18 THERM 90 KD.A, 120 KD.A
Procedure for additionally lling the heating system with water:
1. Disconnect the boiler from the mains.
2. Slowly open the valve for additional lling and monitor manometer on the control panel of the boiler.
3. Set the system pressure to the necessary value (according to the heating system, recommended 1.5 – 2.5 bar)
4. Close the valve for additional lling
5. Connect the boiler to the electricity network and connect the boiler again
!
2.5 Maintenance and service
Regular maintenance is very important for reliable operation, to achieve along service life, and ecient combustion. We
consistently recommend the user to contact aservice organisation in the place of residence and to ensure regular inspections
of the boiler after one year of operation (see chapter: Warranty and Warranty Terms). The service technician will for example,
inspect the control and security elements of the boiler, inspect the tightness of the gas and water distribution or the cleaning
of the burner and the exchanger of burnt dust particles, etc.
During additional lling it is necessary to take the following conditions into consideration:
2.6 Warranty and warranty terms
The producer is not liable for any mechanical damage to individual components by rough handling, for damage caused by
unprofessional intervention into the electronic system during the adjustment and connection of the add-in regulation, for
damages caused by the use of other parts and components than the original components used by the producer.
The warranty is also not applicable to defects caused by non compliance with the binding notications and terms stated in
individual parts of this manual.
The warranty is not applicable to non-standardized relations in distribution networks (variation of electrical voltage – in
particular voltage peaks, pressure and cleanliness of gas, etc.), defects to equipment outside the boiler that inuence activity,
improper collection of burnt gases, dirt in the combustion air, damage from outside inuences, mechanical damage, storage,
transport and defects originated by natural disasters.
In such cases the service organisation may require that the client pays for the repair.
THERMONA provides warranty under the terms and conditions stipulated in the letter of warranty delivered together with
the product.
Terms for application of the warranty:
1. Regular, 1x per year, inspection of the gas boiler. Inspections must only be performed by an authorized organisation,
i.e. contractual service. The list of service centres is attached to each boiler. The actual list of service centres is available
fromwww.thermona.cz
2. Documentation for all records of warranty repairs and annual inspections of boilers is in the appendix to this manual.
3. Submitting completed and conrmed warranty certicate and protocol on commissioning into the operation of THERM
products
a) the pressure of utility water supplied into the boiler must be higher than the water pressure in the heating
system (otherwise the heating water can ow back to the water mains!)
b) the additional lling of water is necessary to be done exclusively under acold status (the temperature of
the heating water in the boiler is amaximum of up to 35 °C)
!The regular inspection of the gas boiler includes apreventive replacement of the sensor detecting the presence
of the ame - ionizing or combined electrodes.
For error-free operation of the heating system, it is also necessary to regularly inspect the initial water pressure in acold
condition. In the case of adecrease of pressure below 0.8 bar, it is necessary to additionally ll the heating system.
The external casing of the boiler can be cleaned with adamp cloth and mild detergent. Donot use cleaning agents based
on sand and solvents that could damage the nish.
2.5.1 Additionally lling the heating system
Water is added to the heating system (system pressurization) through the supply valve which is apart of the heating system.
Water for lling must full certain parameters, see chapter 3.8.

19
THERM 90 KD.A, 120 KD.A
Before installing the boiler the assembly company is obliged to check:
the type of the boiler corresponds to the ordered boiler
the selection of the boiler is correct for the stated use (type of gas, heating system, collection of smoke, air suction)
the delivery is complete
3.2 Complete character of the delivery
THERM hanging boilers are delivered fully assembled. All parts of the boiler
are checked and set by the producer before assembly. Each boiler is tested
for leakage of the water circuit, leakage of the gas circuit and the regulating
and protection parts are set and tested.
3. INSTALLATION MANUAL
3.1 Basic instructions for assembly of the boiler
The THERM 90 KD.A and 120 KD.A hanging boilers are designed for operation in regular hot-water heating systems.
The standard delivery of the boiler includes:
1. Boiler
2. Manual for installation, service and maintenance of boiler
3. Service network (valid for CZE teritory)
4. Letter of warranty (3 copies)
5. Protocol on the commissioning of THERM products into operation
(valid for CZE teritory)
6. Conrmation of completing 1. and 2. service inspection (valid for CZE
teritory)
7. Hanging bar, including xation elements
!Assembly must only be performed by aqualied professional company and it is necessary to pay attention to
all advice and notications contained in this manual. Assembly must be in accordance with valid standards and
regulations – see ČSN EN 1775, ČSN 386462, ČSN 332000 – 7 – 701 ed.2, ČSN 061008, ČSN 734201, TPG 70401,
TPG 80002, TPG 90802, Regulation No. 48/1982 Coll.
Accessories:
Necessary accessories (collection of gases, regulation, outside sensor, etc.) can be ordered on request. Detailed information
can be found in the catalogue of products and accessories or at www.thermona.cz.
!To collect smoke in the „C“ variant, it is necessary to exclusively use equipment to collect gases delivered by
the producer of the boiler. Only by doing this will the boiler report the stated parameters for burning, output,
eciency, etc.
In the case of any doubt or inquiries, contact the producer or supplier before assembly.
1
7
2
34
5
6
Content of delivery

20 THERM 90 KD.A, 120 KD.A
3.3 Location of the boiler
The THERM condensing boilers can be installed in anormal environment rated
as AA5/AB5 according to CSN 332000-5-51 ed.3 (temperature range +5 to 40 °C,
humidity in relation to the temperature up to 85%, without harmful chemical
inuences). The combustion air must not contain halogen-hydrocarbons and
vapours from aggressive substances, and must not have high moisture and
dust levels.
The boilers from the THERM 90 KD.A, 120 KD.A series are usually installed in
non-residential spaces (boiler rooms). If the boiler is installed near the living
area, it is recommended to set alimit to the maximum boiler output (in terms
of the heating requirements of the object) at the lower limit of the loss output
range with regard to lower noise level of the boiler when running at lower
outputs.
The IP 41 (D) protection of electric parts meets the requirements of resistance
to vertically dripping water. The place of installation must be selected to
be able to have access in the case of operation and service inspection. The
recommended distances are stated in the following picture.
Attention:
According to CSN EN 303-1, boilers and ue pipes must be installed at least 100 mm away from ammable material. Flammable
items must not be located at lower distances. The wall on which the boiler will be suspended must be constructed from re-
proof material.
Before starting work that may cause achange of the environment in the area of the installed boiler (e.g. work with painting
substances, glues, etc.), it is necessary to disconnect the boiler using the regime switch (position with the pointer on “0“) and
to disconnect it from the electricity network (remove the network fork from the socket).
3.4 Suspending the boiler
The THERM 90 KD.A and 120 KD.A hanging condensing boilers are mounted on the wall using the hanging strips, delivered
together with the boiler, as shown in the pictures below.
Procedure for hanging the boiler:
1. Consistently measure the position of the suspension of the boiler (according to the diagram with the dimensions)
2. Position the suspension bar on the required place and using aspirit level, balance the bar
3. Mark with apencil the points where holes will be drilled
4. Remove the bar and using aØ10mm drill, drill the necessary holes
5. Insert dowels into the hole and consequently secure it using the attached bolts
6. Suspend the boiler on the bar
7. Install piping for the exhaustion of burnt gases and the air supply. Fill the space between the piping and the hole in the
wall with reproof material (remember to make sure it can be disassembled for smoke collection).
In the case of installation on awall with lower load-bearing capacity, it is recommended to consult the installation with
aservice technician. Around the boiler, due to service inspection or potential service intervention, leave amanipulation area
so to be able to easily work with your hands around the boiler using standard hand held tools.
min.
500 mm
min.
250 mm
min.
500 mm
min. 200 mm
min. 200 mm