Viadrus NAOS K4 User manual

NAOS K4
M
anual for boiler operation and installation
GB_2014_24

2
Table of Contents page
General Information
1. Produced Versions of the Boilers............................................................................................................ 4
2. Boiler Application and Benefits................................................................................................................ 4
3. Technical Data......................................................................................................................................... 5
4. Boiler Description .................................................................................................................................... 7
4.1 Boiler Design...................................................................................................................................... 7
4.2 Control Features................................................................................................................................. 7
4.3 Main Boiler Parts................................................................................................................................ 9
4.4 A diagram showing flue gas flow in the exchanger.......................................................................... 11
4.5 Delivery and Accessory.................................................................................................................... 12
4.5 Instructions before Putting into Operation........................................................................................ 12
User
5. Boiler Attendance by the User............................................................................................................... 13
5.1 Description of the control functions.................................................................................................. 13
5.1.1 Activation of the boiler................................................................................................................ 13
5.1.2 Values shown on the boiler screen............................................................................................ 14
5.2 INFO mod......................................................................................................................................... 15
5.3 Parameter setting............................................................................................................................. 16
5.3.1 Setting the hot water temperature ............................................................................................. 17
5.3.2 Setting the temperature of water to the heating system............................................................ 17
5.3.3 The SUMMER/WINTER switch (version K4G2S24XX and K4G3S24XX) ................................ 18
5.3.4 Temporary activation ................................................................................................................. 18
5.3.5 Setting the anti-cycling period (PR10) ....................................................................................... 19
5.3.6 Setting the pump rundown (PR11) ............................................................................................ 20
5.3.7 Setting the heating curve K-factor (PR15)................................................................................. 21
5.3.8 Shifting of the heating curve (Opentherm)................................................................................. 22
5.3.9 The „***“ (tri star) mode for hot water preheating....................................................................... 23
5.4 Failures ...................................................................................................................................... 24
5.4.1 Failures shown on the boiler screen.......................................................................................... 24
6. Maintenance.......................................................................................................................................... 25
7. IMPORTANT NOTICES ........................................................................................................................ 25
8. Instructions for Product Disposal After Its Service Life......................................................................... 26
9. Warranty and Liability for Defects ......................................................................................................... 26

General Information
3
Servicing
10. Placement and Installation .................................................................................................................... 27
10.1 Standards and regulations ............................................................................................................... 27
10.2 Possible Placement.......................................................................................................................... 28
10.3 Boiler Installation.............................................................................................................................. 29
10.4 Connecting to the Heating System and Water Filling ...................................................................... 31
10.5 Gas Connection................................................................................................................................ 31
10.6 Electric Power Supply Connection................................................................................................... 31
10.7 Condensate Discharge..................................................................................................................... 31
10.8 Flue Gas Ducting.............................................................................................................................. 31
10.9 Boiler Electrical Wiring ..................................................................................................................... 32
10.9.1 Main components of boiler electrical equipment........................................................................ 32
10.9.2 Connection of the higher-level regulation and external boiler sensors...................................... 32
10.9.3 Connecting terminal................................................................................................................... 33
10.9.4 Wiring of the sensors ................................................................................................................. 34
11. Flue Gas Ducting................................................................................................................................... 37
11.1 Flue gas ducting – examples of correct connection of flue duct and air supply............................... 39
11.2 Flue gas ducting – examples of incorrect connection of flue duct and air supply............................ 39
11.3 STARR D80 and FLEX 80 system connection ................................................................................ 39
11.3.1 STARR, 2 x D 80 mm flue ducting diagram............................................................................... 40
11.3.2 FLEX, 2 x D 80 mm flue ducting diagram.................................................................................. 41
11.4 LIK 60/100, 80/125 system connection............................................................................................ 42
11.4.1 Diagram for flue gas ducting of the LIK type, version 60/100 mm (max. length 5 m),
or 80/120.................................................................................................................................... 43
11.5 Pressure Losses of Chimney Flue Elements in Case of NAOS K4 Boiler Usage ........................... 44
12. Commissioning...................................................................................................................................... 45
12.1 Instructions before Putting into Operation........................................................................................ 46
12.2 Boiler Setting.................................................................................................................................... 47
12.3 Conversion to a different type of fuel ............................................................................................... 49
12.4 Boiler Electronics Setting ................................................................................................................. 50
13. Servicing Inspection of the Boiler.......................................................................................................... 52

General Information
4
Dear Customer
Thank you for your purchase of the NAOS K4 boiler and for your confidence in VIADRUS a.s.
To become familiar with a proper operation of your new product since the beginning, please read
carefully the presented user´s manual, especially Chapter No. 5 – Boiler Attendance by the user,
Chapter No. 6 – Maintenance, and Chapter No. 7 – IMPORTANT NOTICES. We ask you to follow the
information presented below and especially to perform the prescribed annual inspections to be
performed by an authorized specialized company, which guarantees a long-term boiler operation free
of failures to both your and our satisfaction.
1. Produced Versions of the Boilers
In your order specify the following:
Order specification code:
NAOS K4 X X X XX X X
Conversion of the NAOS K4 boiler from natural gas to propane and vice-versa can be performed by a
contracted service provider only.
Chimney flue made by ALMEVA has been certified for this boiler. If you use chimney flue made by a
different producer, it is necessary to use a system with identical parameters as for the certified type
of the chimney flue.
2. Boiler Application and Benefits
The NAOS K4 condensing boiler has been designed for combustion of low pressure natural gas.
The size of the condensing boiler is suitable for heating of family houses and recreational facilities as well as
for reconstruction of heat sources in individual apartment units. The condensation heat output is 5 – 24 kW.
The boiler body efficiency at the 50/30 °C temperature gradient varies in a range of 101 – 105 % depending
on the required output.
Boiler Benefits:
•Low gas consumption
•High combustion efficiency
•Smooth output modulation
•Easy attendance and maintenance
•The boiler enables connecting to a reservoir of hot service water heater and ensures its preferential
heating
•Reliability of the regulation and safety components
•Low weight
•Equithermal boiler regulation
Cover color:
W: white
R: red
S: silver
B: black
Output
:
24: 24 kW
Electrical
equipment :
S: SIT
Water heating:
1: without installed three-way
valve with a pump
2: three-way valve, pump, HSW
exchanger
3: with a three-way valve with a
pump
Exchanger:
G: stainless
Sermeta
Fuel:
Z: natural gas
P: propane

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5
3. Technical Data
Tab. No. 1 Sizes, operation temperature and electrical variables
K4G1S24ZX
K4G1S24PX
K4G2S24ZX
K4G2S24PX
K4G3S24ZX
K4G3S24PX
Fuel type [-] ZP Propane ZP Propane ZP Propane
Category of appliance [-] I
2H
I
2E
I
3P
I
2H
I
2E
I
3P
I
2H
I
2E
I
3P
Version C
13
,C
33
, C
43
, C
53,
C
83
Weight [kg] 26 27.5 26.5
Water volume [l] 2 3 2
Boiler dimensions – width [mm] 460
– depth [mm] 320
– height [mm] 720
Ø of combustion air connection [mm] 80
Ø flue gas socket [mm] 80, 60
Working water overpressure [bar] 3
Testing water overpressure [bar] 5
Pressure loss [-] See diagram 1
Maximum permitted working
temperature [°C] 85
Heating water setting range [°C] 25 - 85
Hot water setting range [°C] - 35 - 65 35 - 65
Connecting overpressure of fuel [mbar]
20 37 20 37 20 37
Noise level [dB] < 50
Boiler connection
- heating water output [Js] ¾“
- heating water input to the heater [Js] - ½“ ½“
- return heating water input [Js] ¾“
- return water input from the heater [Js] - ½“ ¾“
- condensate outlet [mm] Ø 25
- safety valve output [mm] Ø 21,2
- gas inlet [Js] 3/4“
Connecting voltage 1/N/PE 230VAC 50 Hz, TN-S
El. power input including pump [W] 110
El. covering IP 40
Tab. No. 2 Thermal – technical parameters
comparison conditions 15 °C and 101.325 kPa, dry gas
K4G1S24ZX
K4G1S24PX
K4G2S24ZX
K4G2S24PX
K4G3S24ZX
K4G3S24PX
Boiler output range [kW] 5 - 24
Nominal output 80/60 °C [kW] 22,2
Nominal output 50/30 °C [kW] P=24
Minimum output 50/30 °C [kW] P=5
Maximum nominal heat input [kW] Q=22.8
Minimum nominal heat input [kW] Q=4.6
HSW flow with ∆T 38 °C [l.min
-
1
] - 8,3 -
Boiler efficiency at the nominal output 80/60°C [%] Up to 98
Boiler efficiency at the nominal output 50/30°C [%] Up to 105
Volume flow rate of fuel [m
3
.h
-
1
] 0.5-2.4 0.2-0.9 0.5-2.4 0.2-0.9 0.5-2.4 0.2-0.9
Mass flow rate of flue gas [kg.h
-
1
] 8 - 45
Nox class [-] 5
Flue gas temperature (max.) [°C] 85

General Information
6
Diagram no. 1 A diagram of the boiler heating circuit hydraulic loss
If the central heating system is fitted by thermostatic valves, it is necessary in order that their correct function
was ensured and noisiness was restrained. For usual installations when the C.H. system is connected on the
boiler, it is necessary to keep the dynamic overpressure in the system at the value of
8 - 15 kPa (0.8 - 1.5 m column of H
2
O). For this purpose a pressure relief valve must be fitted (e.g. Heimeier
HYDROLUX DN 20) in the system. It will be set on the required value of the pressure. The pressure relief
valve is usually fitted next to the boiler.
If the heating system is in a large distance from the boiler, the pressure relief valve may be placed at the
place of the system branching with advantage. The pressure relief valve ensures also the required minimal
flow through in the boiler in a case of radiator valves closing.
Values of the maximal overpressure have been also stated in the graph. They are intended for the individual
adjustments of power output grades of the circulating pump that is available in the heating system. Minimal
flow through the boiler drum is 500 l / hour. From the graph, it follows that the required flow through won't be
reached by exceeding of the maximal dynamic overpressure.
Fig. no. 1 The main boiler dimensions
Volume Flow through of Heat Transfer Media, Water [litters per an hour]
Utilisable Overpressure for Heating System [kPa]

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4. Boiler Description
4.1 Boiler Design
The boiler elementary structure consists in a condensing exchanger made of stainless steel pipes. It is
checked for tightness by test overpressure 5 bar. The boiler is further equipped with a premix burner. The
combustion mixture is mixed in a mixer in the preset air-gas ratio within the entire output range. Air is
supplied to the mixer by a modulation fan.
The boiler is made in three versions:
NAOS K4G1S24XX version designed for heating only is equipped with a circulation pump
NAOS K4G2S24XX version with a circulation pump and flow type hot water (hereafter referred to as
“HSW”) heater
NAOS K4G3S24XX version with a circulation pump and a three-way valve ready to be used in
combination with a reservoir type hot water heater
The SIT automatics is an electronic control and ignition automatics designed for gas-fired central heating
boilers with a modulated fan and burner with preliminary mixing.
The combustion air inlet and the flue gas outlet may be implemented by several means as follows:
- to the chimney,
- through the wall,
- through the roof (either inclined or horizontal),
- to a joint shaft.
The boiler is an appliance in version C, i.e., a closed appliance with electronic ignition and flame ionization.
4.2 Control Features
1 electronic panel with the control panel
2 circulation pump output setting switch
3 valve for adding water to the heating system
Fig. no. 2 The NAOS K4 boiler control panel

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8
•Remove the bolts (1)
•Remove the binding strip (2)
•Pulling the cover side detach the Velcro strip (3) •Remove the front cover
Fig. no. 3 Removing the boiler front cover

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9
4.3 Main Boiler Parts
1 three-way valve (only for versions
K4G2S24XX and K4G3S24XX)
2 HSW temperature sensor (only for version
K4G2S24XX)
3 HSW exchanger (only for version
K4G2S24XX)
4 gas valve
5 siphon
6 safety valve
7 circulation pump
8 gas supply pipe
9 bleeder valve
10 boiler electronics
11 burner plate
12 heating water temperature sensor
13 mixer
14 safety thermostat
15 ignition electrode
16 ionization electrode
17 boiler frame
18 exchanger
19 fan
20 expansion tank
21 name plate
22 boiler front cover
23 pressure gauge
Fig. no. 4 The NAOS K4 boiler assembly (version shown - K4G2S24XX)

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10
1 condensing exchanger
2 input of return water to the exchanger
3 pump
4 input of return water to the pump
5 heating system (radiators)
6 output of hot water from the exchanger
7 input of hot water to the radiators
8 filling valve
Fig. no. 5 NAOS K4G1S24XX with only water heating for the system
(hydraulic diagram of the version and the sketch of the hydro-block)
1 condensing exchanger
2 input of return water to the exchanger
3 pump
4 input of return water to the pump
5 heating system (radiators)
6 output of hot water from the exchanger
7 input of hot water to the radiators
8 three-way valve
9 flow type water heater
10 input of water to the flow type water heater
11 output of water from the flow type water
heater
Fig. no. 6 NAOS K4G2S24XX with a flow type heater
(hydraulic diagram of the version and the sketch of the hydro-block)

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11
1 condensing exchanger
2 input of return water to the exchanger
3 pump
4 input of return water to the pump
5 heating system (radiators)
6 output of hot water from the exchanger
7 input of hot water to the radiators
8 three-way valve
9 filling valve
10 output of hot water from the heater
11 refilling of water to the system
12 reservoir type water heater
13 relief valve of the heater
14 input of water to the heater
Fig. no. 7 NAOS K4G3S24XX the boiler version
(hydraulic diagram of the version and the sketch of the hydro-block)
4.4 A diagram showing flue gas flow in the exchanger
Fig. no. 8 A diagram showing flue gas flow in the exchanger
first heat exchange
water output
50°C
water input
30°C
flue gas after
water
condensation
condensation partition
condensate outlet
water output
water input
condensate
gorące spaliny gazuhot flue gas
flue gas after the first heat exchange
flue gas after the second heat exchange
burner
40 °C

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12
4.5 Delivery and Accessory
The NAOS K4 boiler is delivered as assembled on a pallet, packed in a carton cover. Flue gas ducting is
delivered in accordance with the customer requirements based on the actual connection of air inlet and flue
gas outlet (see chapter 11).
Standard accessory for all boiler versions:
Mounting bracket 1 pcs
Dowel - 8 x 40 mm 5 pcs
Bolt - 5 x 40 5 pcs
Chimney opening reducer piece 1 pcs
External sensor PL10K 1 pcs
Blinding plug D80 1 pcs
Operation and installation manual, including the warranty certificate
A list of contracted servicing organizations
For version NAOS K4G3S24XX (hot water exchanger):
sensor QAZ 36.526/109 1 pcs
Recommended accessory for all boiler versions:
Room thermostat 1 pcs
ALMEVA flue gas ducting, Type: LIK, STAR or FLEX
Water filter
Opentherm (Honeywell CR 04)
The recommended accessory is not included in the boiler standard price.
4.5 Instructions before Putting into Operation
The boiler can only be commissioned by organizations that are authorized and trained for this
purpose by the manufacturer.
The installation shall comply with the regulations that are applicable for this equipment. The boiler shall be
compatible with the local connecting conditions (checking the parameters of the boiler with the information on
the name plate).
During the first start of operation of the boiler it is necessary to instruct the user in accordance with
this manual and to hand over this manual to the user.
Then it is necessary to perform:
- inspection revision before commissioning,
- inspection for any water leakages,
- inspection of instrumentation and safety controls.
Notice:
The ABS boiler cover is protected by a protection foil. This foil needs to be removed before commissioning of
the boiler or 1 month from unpacking the boiler from the packaging carton at the latest. Removing the foil
after this period may be more difficult.

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5. Boiler Attendance by the User
Description of the control panel
1
2
3
4
5
6
Parameters shown on the boiler screen. Basic summary:
Legend for description of the functions:
This symbol indicates the necessity of
restarting the boiler by the user by the
„RESET“ button
This symbol indicates the necessity of
a repair by a servicing organization
Graphic display of a flashing symbol
5.1 Description of the control functions
The symbols and values shown on the screen are described below. The basic information shown on the
screen is the heating circuit temperature – in case of hot water heating it is the temperature measured on the
hot water sensor.
Setting the required temperature of hot water and system water temperature is performed by using buttons
1 - 4 on the boiler control panel.
When the higher level regulation is used, this option is blocked on the boiler and temperatures can be set
using the room instrument only.
5.1.1 Activation of the boiler
The boiler is energized even after turning off and the electronics ensures anti-freezing protection and (if set)
also short operation of the circulation pump in regular intervals to prevent freezing.
1 + HSW temperature up
2 - HSW temperature down
3 + heating water temperature up
4 - heating water temperature down
5 Switch, switchover summer/winter,
RESET, confirmation of selection
1 flame indication
2 call the servicing engineer
3 boiler may be unlocked by
pressing the RESET button
(switch)
4 parameter setting
5 Hot Water mode
6 heating water mode

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Screen
Description
Stand-by mode
To turn on the boiler press down the main switch
button (5) and hold it for some time.
For switching the boiler to the summer mode see
chapter 5.3.3
To turn off the boiler press down the main switch
button (5) and hold it for some time (5 sec).
5.1.2 Values shown on the boiler screen
Screen
Description
Screen
Description
When controlled by the
thermostat, the thermostat
is open
Requirement for refilling of
water to the heating system.
The FL symbol is shown in
the 1s intervals.
Boiler in the summer
mode, the primary circuit
temperature is shown
Preheating of the hot water
circuit. Shown only when
this function is active.
Boiler in the winter mode,
the primary circuit
temperature is shown
HSW heating, current
HSW temperature is
shown
Accident protection active,
bP+temperature flashing
Heating water heating,
current temperature is
shown
Heating water temperature
setting (other symbols not
shown)
Ignition of the burner
Higher level regulation
connected
(4 s interval)
Burner in operation
HSW temperature setting,
(other symbols not shown)
Boiler is off, anti-freezing
function is active
Pump rundown
Ignition of the burner is
postponed due to the
system settings
“Chimney-sweeper” function
LP = output HSW MIN
hP = output MIN
cP = output MAX
dP = output HSW MAX
(setting parameters P09=01)
Indicator of the servicing
inspection requirement.

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15
5.2 INFO mod
Information messages shown on the screen that are used for checking the boiler parameters.
Screen
Multiplier,
units Description
For entering the Info Mode press down button 3 and 5
simultaneously and hold them down for 5 s
Scrolling in the Info Menu by the + and – buttons
d0
Not used
d1
°C Outside temperature (temperature measured by the
outside sensor B9 – if connected)
d2
x 0.1 K-factor
d3
x 0.1 Offset of the heating curve (K-factor) – (see diagram no.
3)
d4
°C Temperature computed on the basis of the outside
sensor
d5
°C Water output temperature
d6
°C Return water temperature
(not shown for the NAOS boiler in the SIT version)
d7
°C Actual temperature HW
d8
°C Flue gas temperature
d9
x 100, rpm Fan revolutions (Ex.: 44x100=4400)
dc
Software version: - burner control
dd
Software version: –the main board
de - c9
Not used
For exiting the Info Mode press down button 3 and 5 simultaneously.

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5.3 Parameter setting
The boiler control varies depending on connecting the boiler to the heating system
Boiler (terminal) wiring
diagram) Description Hot water Heating water
Setting the hot and
heating water
temperature
Boiler without
the room device
and without the
outside sensor.
Boiler control panel
Boiler without
the outside
sensor, room
thermostat
connected.
Boiler control panel
Boiler without
the outside
sensor,
OPENTHERM
room device
with
communication
connected.
Room device
Boiler without
the room
device, the
outside sensor
connected.
Water temperature to the
system is computed
based on the outside
temperature and setting
of the heating curve
K-factor. For changing the
values see chapter 5.3.7
and 5.3.8.
Boiler with the
outside sensor
and the room
thermostat
connected.
Water temperature to the
system is computed
based on the outside
temperature and setting
of the heating curve
K-factor. For changing the
values see chapter 5.3.7
and 5.3.8.
Boiler with the
outside sensor
and
OPENTHERM
room device
with
communication
Water temperature to the
system is computed
based on the outside
temperature and setting
of the heating curve
K-factor. For changing the
values see chapter 5.3.7
and 5.3.8. Changing the
hot water temperature by
the room device only.

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5.3.1 Setting the hot water temperature
When the OPENTHERM higher-level regulation is connected, the screen shows the current temperature.
Changing the hot water temperature setting is done by the room device.
Screen
Description
or Change the temperature setting when the boiler is turned on.
Set the desired temperature using button 3 or 4.
The temperature can be set with a range of 30 – 60 °C.
When you press button 3 or 4 for the first time the screen will show the
current temperature setting and the faucet symbol on the screen will be
flashing.
When the parameters are not changed within 5 s the current temperature
setting will be stored and the boiler will switch to the normal mode.
5.3.2 Setting the temperature of water to the heating system
When the OPENTHERM higher-level regulation is connected, the screen shows the current temperature.
Changing the hot water temperature setting is done by the room device.
When the outside sensor is connected, the temperature of water to the heating system is computed based
on the outside temperature.
Screen
Description
Change the temperature setting when the boiler is turned on.
Set the desired temperature using button 3 or 4.
The temperature can be set with a range of 25 – 85 °C.
When you press button 3 or 4 for the first time the screen will show the
current temperature setting and the radiator symbol on the screen will be
flashing.
When the parameters are not changed within 5 s the current temperature
setting will be stored and the boiler will switch to the normal mode

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5.3.3 The SUMMER/WINTER switch (version K4G2S24XX and K4G3S24XX)
Setting the boiler for summer and winter operation. When the boiler is switched to the summer mode the
requirement for heating of water to the system is ignored.
Screen
Description
Stand-by mode.
To activate the boiler by press down the main switch button (5)
and hold it for some time. The boiler will start operation in the
winter mode.
For switching to the summer mode press down the main switch
button (5) and hold it for 2 s.
Winter mode Summer mode
5.3.4 Temporary activation
Temporary activation of the boiler for heating of water to the heating system – only when the system
is equipped by the outside sensor.
This setting is used to force the boiler to heat water to the heating system. The boiler will be in operation for
a period not longer than 24 h or until switching back to the normal mode.
Screen
Description
or Change the mode setting when the boiler is turned on
Press down buttons 3 and 4 simultaneously
/
The mode is activated
/
The value of the output temperature to the heating system
To deactivate this mode press down buttons 3 and 4
simultaneously
/
The system is deactivated

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5.3.5 Setting the anti-cycling period (PR10)
This parameter is used to prevent frequent starting of the boiler to the heating system. This is the minimum
period of time for which the requirement for heating to the system will be ignored. The default setting is 3
min.
This value does not have any impact on executing the requirement for starting the boiler in case of a
requirement for heating of hot water.
The setting range is 0 – 600 s. The shown value needs to be multiplied by 6, i.e., 10 x 6 = 60 s
Screen
Button
pressing
time Description
or Switching to the servicing mode shall be done when the
boiler is turned on
10 s Switch the boiler to the parameter setting mode by simultaneous pressing of buttons 3, 4 and 5 for a period of
10 s
/
The screen will show PR / 01
Set the required parameter on the screen using button
3 or 4
/
Set the parameter PR / 10 on the screen using button 3 or 4
2s Switch the boiler to the value setting mode by simultaneous
pressing of buttons 3 and 5 for a period of approx. 2 s .
The default setting for anti-cycling period is 3 min.
The setting range is 0 – 600 s. The shown value needs to
be multiplied by 6, i.e., 10 x 6 = 60 s
For switching back without changing the parameters simultaneously press down buttons 4 and 5.
Press
shortly To confirm the set value press shortly button 5 on the main switch
10 s To exit the setting mode simultaneously press down buttons
3, 4 and 5 for 10 s

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5.3.6 Setting the pump rundown (PR11)
This parameter is used to set the pump rundown. The default setting for the rundown is 1 min.
The setting range is 0 – 600 s. The shown value needs to be multiplied by 6, i.e., 10 x 6 = 60 s.
Screen
Button
pressing
time Description
or Switching to the servicing mode shall be done when
the boiler is turned on
10 s Switch the boiler to the parameter setting mode by simultaneous pressing of buttons 3, 4 and 5 for a
period of 10 s
/
The screen will show PR / 01
Set the required parameter on the screen using button 3 or 4
/
Set the parameter PR / 11 using button 3 or 4
2s Switch the boiler to the value setting mode by simultaneous pressing of buttons 3 and 5 for a period
of approx. 2 s.
The default setting for rundown period is 1 min.
The setting range is 0 – 600 s. The shown value
needs to be multiplied by 6, i.e., 10 x 6 = 60 s
For switching back without changing the parameters simultaneously press down buttons 4 and 5.
Press
shortly To confirm the set value press shortly button 5 on the main switch
10 s To exit the setting mode simultaneously press down
buttons 3, 4 and 5 for 10 s