COSMOGAS Adveco MYDENS Series User manual

62403777 - R03 01-01-2019_UK - ADVECO
INSTALLATION, USE
AND MAINTENANCE
MANUAL
MYDENS
GAS WALL-MOUNTED
CONDENSING BOILER

3MYDENS
COSMOGAS
CONTENTS
1 - GENERAL SAFETY WARNINGS..................................................................................................................................................5
1.1 - National installation laws.......................................................................................................................................................5
2 - GENERAL INFORMATION ...........................................................................................................................................................6
2.1 - Presentation..........................................................................................................................................................................6
2.2 - Overview of models ..............................................................................................................................................................6
2.3 - Accessories included ............................................................................................................................................................7
2.4 - Manufacturer.........................................................................................................................................................................7
2.5 - Meaning of symbols used .....................................................................................................................................................7
2.6 - Maintenance .........................................................................................................................................................................7
2.7 - Disposal ................................................................................................................................................................................7
3 - MAIN COMPONENTS...................................................................................................................................................................8
4 - OPERATION ...............................................................................................................................................................................10
4.1 - Operation and intended use of the appliance .....................................................................................................................12
4.2 - Characteristic residual head curves at the central heating system.....................................................................................13
4.3 - Characteristic curve of the domestic hot water head losses...............................................................................................13
5 - INSTALLATION ...........................................................................................................................................................................14
5.1 - Opening the package..........................................................................................................................................................14
5.2 - Dimensions and minimum distances to be observed .........................................................................................................14
5.3 - Choosing where to install the appliance .............................................................................................................................14
5.4 - Delivery and return..............................................................................................................................................................14
5.5 - Low-temperature systems (or underoor heating)..............................................................................................................15
5.6 - Domestic hot and cold water...............................................................................................................................................15
5.7 - Gas .....................................................................................................................................................................................15
5.8 - Unit assembly .....................................................................................................................................................................16
5.9 - Condensate drain................................................................................................................................................................16
5.10 - Safety valve ......................................................................................................................................................................16
5.11 - Hydraulic and gas connections, and mounting of the lower cover....................................................................................17
5.12 - Hydraulic connections for model -- B boiler ......................................................................................................................18
5.13 - Polyphosphate softener (on request)................................................................................................................................18
5.14 - Electrical connections: details...........................................................................................................................................19
5.14.1 - Connecting the power supply cable ....................................................................................................................20
5.14.2 – Choosing the room thermostat/ chronothermostat.............................................................................................20
5.14.3 - Connecting the room thermostat/ chronothermostat...........................................................................................21
5.14.4 - CR04 remote time control (on request)...............................................................................................................21
5.14.5 - Installing the external temperature sensor (on request) .....................................................................................21
5.14.6 - 0-10 VDC type dialogue......................................................................................................................................21
5.14.7 - Alarm contact ......................................................................................................................................................21
5.15 - Connecting appliances in a cascade ................................................................................................................................22
5.16 - Connecting the boiler to indirect water heater with coil ....................................................................................................23
5.16.1 - Anti-legionella......................................................................................................................................................23
5.17 - Burned gas exhaust and combustion agent air intake pipe ..............................................................................................24
5.17.1 - Type of intake/exhaust B23 and B23P................................................................................................................25
5.17.2 - “Split 80/80PP” system (polypropylene) (type C43; C53; C83; C93) ..................................................................26
5.17.3 - “Split 80/80PP” system (type C43; C53; C83; C93): accessories available........................................................27
5.17.4 - “Split 80/80PP” system (type C43; C53; C83; C93): installation examples ........................................................28
5.17.5 - “60/100PP vertical coaxial” system (polypropylene) (type C13; C33).................................................................29
5.17.6 - “60/100PP horizontal coaxial” system (polypropylene) (type C13; C33) ............................................................30
5.17.7 - “60/100PP coaxial” system: accessories available .............................................................................................31
5.17.8 - “60/100PP coaxial” system: installation examples..............................................................................................32
5.17.9 - “80PP single” system (polypropylene) (type B23 or B23P).................................................................................33
5.17.10 - “80PP single” system: accessories available....................................................................................................34
5.18 - Installing and uninstalling the MYDENS external cover kit (on request)...........................................................................34
6 - START-UP...................................................................................................................................................................................37
6.1 - Start-up ...............................................................................................................................................................................37
6.1.1 - Instructions to the user..........................................................................................................................................37
6.1.2 - Filling the condensate drain siphon ......................................................................................................................37
6.1.3 - Filling the central heating system..........................................................................................................................37
6.2 - General recommendations regarding the gas supply .........................................................................................................38
6.3 - Type of gas for which the appliance is set. .........................................................................................................................38
6.4 - Conversion of the appliance from one type of gas to another ............................................................................................39
6.5 - Ignition ................................................................................................................................................................................41
6.6 - Controlling the supply gas pressure and any adjustments .................................................................................................41
6.7 - Controlling the level of CO2 and any adjustments..............................................................................................................42
6.8 - Adjusting the power in central heating mode (Range Rated) .............................................................................................44
6.9 - Adjusting the domestic hot water ow rate .........................................................................................................................44
7 - USE.............................................................................................................................................................................................45
7.1 - Checking the cock opening.................................................................................................................................................45
7.2 - Checking the central heating system pressure...................................................................................................................45

4
MYDENS COSMOGAS
CONTENTS
7.3 - Generali information............................................................................................................................................................46
7.4 - Ignition procedure ...............................................................................................................................................................46
7.5 - Summer operating mode ....................................................................................................................................................46
7.6 - Winter operating mode........................................................................................................................................................46
7.7 - Adjusting the instantaneous domestic hot water.................................................................................................................47
7.8 - Central heating....................................................................................................................................................................47
7.9 - Thermostatic adjustment.....................................................................................................................................................48
7.10 - Climatic adjustment...........................................................................................................................................................48
7.10.1 - Climatic adjustment: which systems? .................................................................................................................48
7.10.2 - Climatic adjustment: precautions during adjustment ..........................................................................................48
7.10.3 - Climatic adjustment: setting the parameters.......................................................................................................48
7.10.4 - Climatic adjustment: adaptation to different climatic areas.................................................................................49
7.10.5 - Climatic adjustment: switching the central heating service on and off................................................................49
7.10.6 - Climatic adjustment with room compensation.....................................................................................................49
7.11 - Timers for the various functions ........................................................................................................................................51
7.12 - Pump and diverter valve anti-block function .....................................................................................................................51
7.13 - Anti-freeze protection ........................................................................................................................................................51
7.14 - Automatic system lling (on request) ................................................................................................................................51
7.15 - “User prole” .....................................................................................................................................................................52
7.16 - “Installer prole” ................................................................................................................................................................54
7.16.1 - Parameters for cascade systems........................................................................................................................58
7.17 - Diagnostics .......................................................................................................................................................................59
7.17.1 - Diagnostics: locks “Loc” ......................................................................................................................................59
7.17.2 - Diagnostics: errors “Err”......................................................................................................................................62
7.17.3 - Diagnostics: alarms “AttE” ..................................................................................................................................65
8 - MAINTENANCE ..........................................................................................................................................................................66
8.1 - General recommendations..................................................................................................................................................66
8.2 - Maintenance protocol..........................................................................................................................................................67
8.2.1 - Checking the system water pressure and any leaks.............................................................................................67
8.2.2 - Checking the gas pressure and any leaks ............................................................................................................67
8.2.3 - Checking the condition of the safety valve............................................................................................................67
8.2.4 - Checking the condition of the safety and control devices .....................................................................................68
8.2.5 - Checking the condition of the electrical system ....................................................................................................68
8.2.6 - Checking the operation of the main switch ...........................................................................................................68
8.2.7 - Checking the correspondence of the adjusted temperatures in the heating and domestic hot water systems ....68
8.2.8 - Checking if the device is triggered in case of gas failure ......................................................................................68
8.2.9 - Checking the condition of the air intake and ue exhaust ducts ...........................................................................68
8.2.10 - Checking the ignition and detection electrodes .................................................................................................68
8.2.11 - Checking the condition of the air vent valves......................................................................................................68
8.3 - Removing the casing and accessing the internal components...........................................................................................69
8.4 - Dismantling the burner fan assembly..................................................................................................................................70
8.5 - Cleaning the burner and the primary heat exchanger (fumes side)....................................................................................70
8.6 - Correctly positioning the ignition and detection electrodes ................................................................................................71
8.7 - Dismantling the ignition and detection electrodes .............................................................................................................71
8.8 - Dismantling and replacing the gas valve ............................................................................................................................72
8.9 - Checking the expansion tank..............................................................................................................................................73
8.10 - Cleaning the condensate conveyor siphon.......................................................................................................................74
8.11 - Removing the air vent valve..............................................................................................................................................75
8.12 - Replacing the pump motor................................................................................................................................................75
8.13 - Removing the central heating circuit pressure sensor......................................................................................................75
8.14 - Removing the diverter valve servomotor ..........................................................................................................................76
8.15 - Removing the diverter valve .............................................................................................................................................76
8.16 - Removing the ow meter ..................................................................................................................................................76
8.17 - Removing the safety valve................................................................................................................................................77
8.18 - Secondary heat exchanger for the production of DHW ....................................................................................................77
8.19 - Emptying the appliance on the central heating side .........................................................................................................78
8.20 - Emptying the appliance on the domestic hot water side...................................................................................................78
8.21 - Minimum and maximum power ........................................................................................................................................78
8.22 - Checking the ionisation current ........................................................................................................................................79
8.23 - Checking combustion efciency........................................................................................................................................79
8.24 - Water temperature measurement sensors .......................................................................................................................79
8.25 - External temperature sensor.............................................................................................................................................79
8.26 - Wiring diagram..................................................................................................................................................................80
9 - TECHNICAL DATA ......................................................................................................................................................................82
10 - COMMAND MENU DIAGRAM..................................................................................................................................................84
11 - EU DECLARATION OF CONFORMITY ....................................................................................................................................85
12 - ErP PRODUCT SHEET.............................................................................................................................................................86

5MYDENS
COSMOGAS
If you smell gas
1. - Close the gas cock.
2. - Ventilate the room.
3. - Do not switch on any electric device, telephone included.
4. - From another room, call a professionally qualied technician
immediately or the gas supply company. Call the Fire Service
if the former are not available.
If you can smell combustion products
1. - Switch the appliance off.
2. - Ventilate the room.
3. - Call a professionally qualied technician.
Explosive or highly ammable products
Do not store or use explosive or highly ammable materials
such as paper, solvents, paints, etc. in the room where the
appliance is installed.
Installation, modications
The gas appliance must be installed, calibrated or modied
by professionally qualied staff, in compliance with national
and local regulations, as well as the instructions in this
manual.
Incorrect installation or poor maintenance can cause
damage or injury to persons, animals or objects, for which
the manufacturer cannot be deemed liable.
The appliance exhaust must be connected to a burned
gas evacuation pipe. Failure to comply with this regulation
leads to serious risks for the safety of persons and animals.
A domestic hot water temperature level exceeding 51°C
can cause permanent damage or injury to persons, animals
and objects. In particular, protect children, the elderly and
people with disabilities against any possible risks of scalds,
by inserting devices that limit the usage temperature of the
DHW to users.
The parts conducting the fumes must not be modied.
Do not obstruct the ends of the intake/exhaust pipes.
Do not leave parts of the packaging and any replaced parts
within the reach of children.
Seal the adjustment devices after every calibration.
In agreement with the provisions for use, the user must
keep the installation in good working order and guarantee
reliable and safe operation of the appliance.
The user must have maintenance performed on the
appliance by a professionally qualified technician in
compliance with national and local regulations and this
manual.
We would also highlight the convenience of an annual
scheduled maintenance contract with a professionally
qualied technician.
Before performing any cleaning or maintenance operations,
disconnect the appliance from the mains power supply and/
or use the cut-off devices.
After having performed any cleaning or maintenance
operations, make sure that all internal parts of the appliance
are dry before re-connecting the electric power supply.
This appliance is not intended for use by persons (including
children) with reduced physical, sensory and mental
capabilities or a lack of experience or knowledge, unless
they are supervised or have been instructed on use of the
appliance by a person responsible for their safety.
This manual is an integral and essential part of the
product and must be kept carefully by the user for future
consultation. If the appliance needs to be transferred or if
you should move and leave the unit to another user, always
ensure that this manual remains with the new user and/or
installer.
Any optionals or kits added later must be original Cosmogas
products.
This appliance must be intended only for the use for which
it has been expressly declared: central heating water for
closed circuits intended for central heating of rooms for
civil and domestic use, production of domestic hot water
for civil use.
Any contractual and non-contractual liability on the part
of the manufacturer is excluded for damage caused by
installation errors or usage errors and, in all cases, following
a failure to comply with the instructions given by the
manufacturer or with applicable national and/or local laws.
For safety reasons and to safeguard the environment, the
packaging components must be disposed of in the relevant
separate waste collection centres.
In case of breakdown
In the event of a fault and/or poor operation of the appliance,
disconnect it and do not attempt to carry out any repairs.
Contact a professionally qualified technician only. If
components need to be replaced, these must be original spare
parts. Failure to comply with the above may jeopardise the
safety of the appliance.
Professionally qualied technicians.
A ‘professionally qualied technician’ means a person with
specic technical skill in the sector of central heating system
components and the production of domestic hot water for
sanitary and civil uses, electric installations, and systems for
the use of combustible gas. Such people must have the skills
envisaged by the law.
Technical drawings
All the drawings shown in this manual relating to electrical,
hydraulic or gas installation systems must be understood to be
purely illustrative. All the safety devices, auxiliary devices and
the diameters of the electrical, hydraulic and gas pipes must
always be checked by a professionally qualied technician,
to make sure they satisfy the applicable laws and regulations.
1.1 - National installation laws
Respect the national regulations, provisions, directives and
laws in force.
- Ministerial Decree n°37 dated 22/01/2008 (former Law n°46
dated 05/03/90)
- Law n° 10 dated 09/01/91
- Presidential Decree n° 412 dated 26/08/93
- Presidential Decree n° 551 dated 21/12/99
- Legislative Decree n° 192 dated 19/08/05
- Legislative Decree n° 311 dated 29/12/06
- UNI 7129-1 standard
- UNI 7129-2 standard
- UNI 7129-3 standard
- UNI 7129-4 standard
- UNI 7129-5 standard
- UNI 7131 standard
- IEC 64-8 standard
1 - GENERAL SAFETY WARNINGS

6
MYDENS COSMOGAS
2.1 - Presentation
Congratulations! You have purchased one of the best products on the market.
Each individual part is proudly designed, manufactured, tested and assembled within the COSMOGAS
facilities, thus guaranteeing the best quality control.
2.2 - Overview of models
MYDENS XXY
“P” = Boiler for the instantaneous production of DHW and central heating;
“B” = Boiler set up for coupling to an indirect water heater with coil;
“C” = Central heating only boiler;
15 = Boiler with maximum heat input of 14 kW
24 = Boiler with maximum heat input of 25 kW
34 = Boiler with maximum heat input of 32 kW
Gas condensing boiler tted with a full premix burner.
2 - GENERAL INFORMATION

7MYDENS
COSMOGAS
2.4 - Manufacturer
COSMOGAS srl
Via L. da Vinci 16
47014 - Meldola (FC) Italy
Tel. [phone]
Fax. [phone]
www.cosmogas.com
[email protected]
2.5 - Meaning of symbols used
WARNING!
Electric shock hazard Failure to comply with these warnings
may jeopardise the working order of the appliance or cause
serious damage or injury to persons, animals or objects.
Generic hazard
Failure to comply with these warnings may jeopardise the
working order of the appliance or cause serious damage or
injury to persons, animals or objects.
Important indication symbol
2.6 - Maintenance
A regular annual maintenance check on the appliance is
advised for the following reasons:
- to maintain high efciency and manage the central heating
system economically (with low fuel consumption);
- to achieve a high level of operating safety;
- to maintain the level of environmental compatibility of the
combustion high;
To do this, please see the table in section 8.2.
Offer your customer a scheduled maintenance contract.
2.7 - Disposal
The crossed wheelie bin symbol means that the product
must not be thrown away in the ordinary rubbish bin (i.e. in
with “mixed urban rubbish”); it must be dealt with separately,
in order to undergo suitable operations for it to be reused or
treated, so that any substances that are dangerous for the
environment can be removed and disposed of safely. This
will enable all the raw materials to be recycled. The user is
responsible for getting rid of the boiler at the end of its life,
delivering it to a recycling centre run by the local authority or
city hygiene companies, or, when he/she buys a new boiler,
giving the product that has been replaced to the dealer, who is
obliged to take it under the terms of EU Directive 2012/19/EU.
For further information regarding correct decommissioning
of these units, users can contact the public service in charge
or retailers.
2 - GENERAL INFORMATION
2.3 - Accessories included
The boiler is supplied with the following accessories:
Quantity No. Description Code Figure
n° 1 LOWER COVER 61405266
n° 1 GAS CONVERSION KIT
For 15 and 24 models 62630310
For 34 models 62630311
n° 1 INDIRECT WATER HEATER SENSOR Only for “B” (factory assembled) and “C”
models 62110071
n° 1 PREINSTALLATION TEMPLATE 61804018
n° 1 CONNECTIONS KIT
(including appliance wall support KIT)
For all 15 and 24 “C”, “B” and “P” models 62629825
For all 34 “C”, “B” and “P” models 62629826
n° 1 CONNECTIONS KIT Only for “B” models 62629816

8
MYDENS COSMOGAS
1 - Command and control board
2 - Electric connections board
3 - ----------
4 - Lower cover
5 - Secondary heat exchanger for domestic hot water
6 - Central heating water pressure sensor
7 - Safety valve
8 - Fan
9 - Air/gas manifold
10 - ----------
11 - ----------
12 - Detection electrode
13 - Expansion tank
14 - Support attachments
15 - ----------
16 - Air intake and burned gas exhaust ttings
17 - Combustion analysis points
18 - Fumes temperature sensor (Par. 1006) and ue gas
temperature fuse
19 - Spark generator
20 - Ignition cables
21 - ----------
22 - Air inlet manifold
23 - Back ue preventer valve
24 - Gas valve
25 - Circulation pump
26 - ----------
27 - Front casing
28 - Domestic hot water ow meter
29 - Domestic hot water ow meter sensor (Par.1062)
30 - Display
31 - Control panel
32 - ----------
54 - Primary heat exchanger fuse
3 - MAIN COMPONENTS
Figure 3-1 – Boiler internal components
14
28
29
14
54
5
25
24
20
22
4
8
2
16 18
7
23
19
6
12
17
9
13
1
3130
27
020002.01.002

9MYDENS
COSMOGAS
33 - Front casing couplings
34 - Titanium-plated steel primary heat exchanger
35 - Double supply temperature sensor (Par. 1001 and
1005)
36 - Return temperature sensor (Par. 1007)
37 - Hydraulic supply unit
38 - By-pass pipe
39 - Central heating circuit drain cock
40 - Central heating circuit drain cock
41 - Domestic hot water temperature sensor (Par. 1002)
42 - System ll cock
43 - Condensate collection tank
44 - Safety valve drain pipe
45 - Return hydraulic unit
46 - Air vent valve
47 - 3-way diverter valve
48 - Air vent valve drain pipe
49 - Condensate drain siphon
50 - Air/gas mixing unit
51 - Burner
52 - Drain pipe for any water coming from the combustion
agent air pipe
53 - Ignition electrodes
54 = Primary heat exchanger fuse (not present)
3 - MAIN COMPONENTS
Figure 3-2 – Boiler internal components
53
36
51
34
39
33
38 40 41
37
35
49
52
44
50
47
48
43
46
45
42
020002.01.003

10
MYDENS COSMOGAS
4 - OPERATION
Figure 4-1 – Hydraulic layout
MYDENS 24P
MYDENS 34P
Figure 4-2 – Hydraulic layout
MYDENS 15B
MYDENS 24B
MYDENS 34B

11 MYDENS
COSMOGAS
Key for gures 4-1, 4-2, 4-3:
1 = Boiler
2 = Combustion agent air inlet
3 = Fumes outlet
4 = Fumes temperature sensor (Par. 1006) and ue gas
temperature fuse
5 = Sealed chamber
6 = ----------
7 = Water collection pipe coming from the combustion agent
inlet pipe
8 = Expansion tank
9 = Supply temperature sensor (Par. 1001)
10 = Supply temperature safety sensor (Par. 1005)
11 = Burner
12 = Titanium-plated stainless steel VRC type heat exchanger
13 = Fan
14 = Return temperature sensor (Par. 1007)
15 = Condensate collection siphon with sediment decanter
16 = Air/gas mixer
17 = Pneumatic gas valve
18 = Safety valve
19 = Central heating water pressure sensor (Par. 1033)
20 = Circulation pump
21 = Air vent valve
22 = Diverter valve
23 = Plate heat exchanger for domestic hot water
24 = Domestic hot water temperature sensor (Par. 1002)
25 = Central heating by-pass valve
26 = Domestic hot water ow meter (Par. 1062)
27 = Domestic hot water lter
28 = Supply circuit drain cock
29 = Return circuit drain cock
30 = Central heating system ll cock
31 = Central heating circuit supply
32 = Domestic hot water outlet
33 = Gas inlet
34 = Domestic cold water inlet
35 = Central heating circuit return
36 = Collector for condensate drain and safety valve
37 = Central heating system
38 = Domestic hot water system
39 = Water supply attachment for lling the system
40 = Supply to indirect water heater
41 = Return from indirect water heater
42 = Expansion tank for indirect water heater
43 = Hydraulic safety unit
44 = Cold water supply
45 = Safety valve
46 = Cold water
47 = Domestic hot water
48 = Indirect water heater
49 = Indirect water heater temperature sensor (Par. 1002)
50 = Primary heat exchanger fuse (not present)
Figure 4-3 – Hydraulic layout
MYDENS 15C
MYDENS 24C
MYDENS 34C
4 - OPERATION

12
MYDENS COSMOGAS
4.1 - Operation and intended
use of the appliance
This product is a condensing, gas appliance, intended
for the generation of central heating and production of
domestic hot water for civil use.
Make the adaptation between the boiler and the system,
selecting the characteristic residual head curve in gure 4-5
deemed most suitable from those available.
The maximum useful output power is always guaranteed for
the production of domestic hot water, as the central heating
service switches off at every request for domestic hot water.
The temperature of the domestic hot water is adjusted
following the procedure in section 7.7.
The following types of systems can be set up depending on
the model:
A) - MYDENS -- “P”. With this boiler it is possible to create
a system to produce instantaneous domestic hot water
and a central heating system with the heating elements
operating at a temperature between 30°C and 80°C. An
example of this type of set-up is given in g. 4-1.
B) - MYDENS -- “B”. With this boiler it is possible to create
a system to produce domestic hot water via a coil-type
storage indirect water heater and a central heating system
with the heating elements operating at a temperature
between 30°C and 80°C. An example of this type of set-up
is given in g. 4-2.
C) - MYDENS -- “C”. With this boiler it is possible to create
a system for central heating only with the heating elements
operating at a temperature between 30°C and 80°C. An
example of this type of set-up is given in g. 4-3.
This model can be connected to a coil-type indirect water
heater also after installation, lled via a diverter valve or a
pump outside the boiler.
In all of the boiler versions previously described, connecting
the domestic hot water service is not essential; if the boiler
is used for central heating only, just connect the cold water
pipe to ll the central heating system and close the DHW
outlet tting.
All boiler versions previously described, can be connected
to a room thermostat for adjustment of the central heating.
To perfect the quality of the heating service, an external
temperature sensor can be connected (climatic adjustment)
to automatically adjust the supply temperature depending
on the external temperature. In this case, the room
thermostat can compensate for the room temperature via
an ON /OFF or two-step command.
For further information regarding climatic adjustment, refer
to section 7.10.
This appliance must be connected to a central heating
system and to a domestic hot water distribution network,
compatible with the features, performance and power of
the appliance itself.
Before installing the appliance, the central heating
system and the domestic hot water system must be
washed thoroughly in order to remove any residues or
impurities, which could compromise the working order of
the boiler.
This boiler is not designed to be installed in the open air;
it must not be exposed to temperatures below 0.5°C and
above 50°C. Choose a place sheltered from weathering
and frost. If the appliance is equipped with a special
external cover kit (see section 5.18) it can be installed
outside, in a place partially protected from rain, snow and
hail, such as a balcony or porch (see gure 4-4).
Check gure 5-1 concerning the minimum safety
distances for installation and future maintenance.
4 - OPERATION
Figure 4-4 – Example of a partially protected place
Figure 4-4 key – Distances “A” and “B” must
be assessed during installation so that rain
does not reach the appliance directly.

13 MYDENS
COSMOGAS
0
50
100
150
200
250
300
350
400
450
500
550
600
650
0 100 200 300 400 500 600 700 800 900 1000 1100 1200 1300
X
RIC27-2013
H (mbar)
Q (l/h)
4.2 - Characteristic residual head
curves at the central heating system
The residual head at the appliance connections is given as
a graph in gure 4-5.
The modulation range (particularly “x”) can be checked
using the graph in gure 4-5.
4 - OPERATION
Figure 4-5 – Residual head
Figure 4-6 – Domestic hot water losses curve
0
0,5
1
1,5
2
2,5
3
0 3,3 6,6 10 13,3 16,6
RIC17 - 2012
Head losses (bar)
Water ow rate (l/min)
4.3 - Characteristic curve of the
domestic hot water head losses
Each boiler exerts resistance to the passage of domestic
hot water (see the ow rate/pressure graph in gure 4-6).
The installer or project technician must take this into
consideration in order to guarantee the correct domestic hot
water ow rate to the utility.

14
MYDENS COSMOGAS
5.1 - Opening the package
Take the product out of the cardboard box and remove any
protective lm.
5.2 - Dimensions and minimum
distances to be observed
For both installation and maintenance, it is necessary to leave
free spaces around the boiler, as shown in gure 5-1.
5.3 - Choosing where to
install the appliance
WARNING! The appliance must be installed
exclusively on a solid, vertical wall, which can bear the
weight.
The appliance must be installed inside your home, or
otherwise protected from atmospheric agents such as rain,
wind, sun, and especially freezing.
Choose the room and suitable position for installation,
taking into account the following factors:
- connection of the fumes exhaust/air intake pipes;
- connection of the gas supply pipe;
- connection to the water supply;
- connection to the central heating system;
- connection to the domestic hot water system;
- electric connection;
- connection to the drain for the condensate produced by
the boiler;
- electric connection of the room thermostat (where
applicable);
- connection to safety valve outlet;
- connection to the external temperature sensor (where
applicable);
This appliance must be installed in a place where
water leakages from the appliance itself, from the joints
between the pipes or from any drainage from the safety
valve, cannot cause damage to materials or items below
it.
5.4 - Delivery and return
WARNING! This boiler has a safety valve
calibrated at 3 bar. Therefore, it must not be installed
with a water head over 30 m.
WARNING! COSMOGAS is not liable for any
damage caused by incorrect use of additives in the
central heating system.
WARNING! The system after the appliance must
be made with materials that resist temperatures up to
95°C and pressure of 3 bar. Otherwise (e.g. with plastic
piping), the system must be tted with the relevant
protection and safety devices.
Before connecting the central heating pipes, wash the
system thoroughly to eliminate any waste (hemp, radiators
casting sand, etc.), which could damage the appliance. This
must also be performed if the appliance is replaced.
Figure 5-2 shows the positioning of the supply and return
ttings.
1 - Central heating supply
3/4" in the 15 and 24 models
1" in the 34 model
2 - 1/2" DHW output (“P” models only)
2 - 3/4" indirect water heater supply (“B” models only)
2 - (not in “C” models)
3 - 3/4" indirect water heater return (“B” models only)
4 - 3/4" gas inlet
5 - 1/2" cold water inlet
6 - Central heating return
3/4" in the 15 and 24 models
1" in the 34 model
7 - Fumes exhaust
8 - Support attachments
9 - Ø20 condensate drain
5 - INSTALLATION
Figure 5-1 – Minimum safety distances
Figure 5-2 – Boiler dimensions and attachments
centre-to-centre distances

15 MYDENS
COSMOGAS
5 - INSTALLATION
Install a metal mesh lter on the return pipe in order to
stop any system residues before they return to the boiler.
Do not use the appliance to introduce any type of
additive into the system.
A continuous intake of water into the central heating
circuit increases the content of oxygen and limescale,
with a risk of corrosion inside the heat exchanger body.
This reduces the boiler’s lifespan. Any leaks from the
central heating circuit must be repaired to prevent the
problem.
5.5 - Low-temperature systems
(or underoor heating)
WARNING! The system after the appliance must
be made with materials that resist temperatures up to
95°C and pressure of 3 bar. Otherwise (e.g. with plastic
piping), the system must be tted with the relevant
protection and safety devices.
WARNING! When installing the boiler in a
low-temperature system, set parameters 2024 and
2111 to 45°C and parameters 2023 and 2110 to
20°C (see section 7.16).
With this setting, the boiler will adjust the supply to a
temperature between 20°C and 45°C. No adjustment from
the command panel (also via climatic adjustment) can
supply water at a temperature over 45°C.
WARNING! If the boiler is installed in an
underoor system made with plastic piping, all of the
necessary precautions must be taken against corrosion
due to oxygen in the water:
make sure that the system is made with plastic pipes
with oxygen permeability not exceeding 0.1 g/m3 at
40°C. Should the pipe not meet these characteristics, the
radiant panel circuit must be isolated from the boiler, via
a plate heat exchanger suitable for resisting the corrosion
generated by the oxygen dissolved in the water.
5.6 - Domestic hot and cold water
WARNING! If water hardness exceeds 25°F, we
recommend installing a polyphosphate softener (see
section 5.13).
WARNING! Install a lter with mesh no wider
than 0.5 mm² in the domestic cold water inlet.
WARNING! The domestic hot water circuit must
be made with materials resistant to temperatures of
at least 95°C and a pressure of 10 bar. Otherwise (e.g.
with plastic piping), the system must be tted with the
relevant protection and safety devices.
WARNING! If the appliance is connected to a
domestic hot water recirculation circuit, install a safety
valve and an expansion tank of a suitable size for
managing the natural increase in the volume of water
during heating.
In gure 5-2, you can verify the position of the domestic hot
and cold water ttings.
Insert a closing cock before the cold water inlet, useful for
maintenance work.
Connecting the domestic hot water service is not essential;
if the boiler is used for central heating only, connect the cold
water pipe to ll the central heating system and close the
DHW outlet.
5.7 - Gas
WARNING! Do not power the appliance with
gases other than those specied.
WARNING! Check that the gas and supply
pressure are those for which the boiler has been
adjusted.
Two situations are possible:
A - the gas and supply pressure correspond to the
adjustment of the boiler. In this case, it can be
connected;
B - the gas and supply pressure do not correspond to the
adjustment of the boiler. In this case, the boiler must
be converted to the type of gas and supply pressure
corresponding to those of the supply available.
The boiler is supplied with the special gas conversion kit.
Before installation, clean the inside of the gas supply
pipe thoroughly;
Install a shut-off cock on the gas supply pipe;
To prevent damage to the appliance gas control unit, run
a leak test at a pressure not exceeding 50 mbar;
If the gas system must be inspected at pressures over
50 mbar, turn the cock positioned immediately before the
boiler, to isolate it from the system.
Use gure 5-2 to check the position of the appliance gas
tting. The cross-sections of the pipes in the gas supply
system must always guarantee a gas supply that is
sufcient to cover the maximum requested.

16
MYDENS COSMOGAS
Figure 5-3 – Support plugs
5 - INSTALLATION
5.8 - Unit assembly
Refer to gure 5-3:
1.- put the paper template, provided with the appliance,
against the wall;
2.- check that the template is square;
3.- mark the holes for the plugs and hydraulic ttings on the
wall;
4.- remove the paper template;
5.- make the holes “A” and insert the wall plugs “B”;
6.- make the boiler hydraulic and gas connections;
7.- hang the boiler on the plugs “C”;
8.- make the hydraulic connections.
5.9 - Condensate drain
There is a siphon inside the boiler for the evacuation of
condensate (see gure 3-2, detail “49”) and to prevent
combustion products from escaping. The end of the siphon
is pipe “F” in gure 5-4. This end must be conveyed into
another, anti-odour siphon (gure 5-6, detail “G”) to prevent
bad odours returning to the environment (the anti-odour
siphon “G” is supplied on request).
In particular, the condensate drain system must:
be for rooms used for residential purposes and for
ofces with more than 10 users; it can be connected
to the domestic waste disposal plant by means
of appropriate siphon with disjunction, capable of
preventing the pressurisation of the system (the siphon
is inside the boiler) and the return of bad odours from
the sewers (detail “G” in gure 5-6). If the room used for
ofce purposes has fewer than 10 users, before up the
domestic waste drain, install a condensate neutraliser
(see section 9 for the acidity value of the condensate and
the quantities).
be performed with a pipe with an internal diameter equal
to or greater than 13 mm;
be installed in such a way as to prevent the liquid
from freezing; therefore pay attention to any external
sections. It is prohibited to drain into gutters or rainwater
drainpipes;
slope continuously towards the drain point; avoid high
points, which could pressurise the pipe;
5.10 - Safety valve
The appliance is protected against overpressures by a
safety valve calibrated to 3 bar (see gure 3-1 detail “7”).
The safety valve drain must be conveyed to pipe “F” in
gure 5-4, which must be then taken to the anti-odour
siphon (detail “G”, gure 5-6). This drain with a siphon is
used to prevent overpressures if the valve is opened, and it
allows the user to check intervention.
The anti-odour siphon “G” in gure 5-6 is provided on
request.
WARNING! If the safety valve is not connected
to the drain, whenever the valve intervenes, it could
cause damage to persons, animals or objects.
Figure 5-4 – Condensate drain pipe
F
020002.01.017

17 MYDENS
COSMOGAS
Figure 5-5 – Water and gas connections
5 - INSTALLATION
EBA F
G
C DH
020002.01.004
Figure 5-6 – Siphon funnel (on request)
F
G
020002.01.028
min10 mm
max 30 mm
5.11 - Hydraulic and gas connections,
and mounting of the lower cover
The boiler is provided with the ttings illustrated in gure
5-5 as standard, where:
A = central heating supply
Ø 18 in the 15 and 24 models
Ø 22 in the 34 model
B = domestic hot water Ø 14 (absent in the “B” and ”C” models)
C = 3/4" gas inlet cock (EN 331 type-approved)
D = 1/2" domestic cold water inlet cock
E = gas Ø 18
F = domestic cold water Ø 14
G = central heating return
Ø 18 in the 15 and 24 models
Ø 22 in the 34 model
Once the hydraulic and gas connections have been made,
proceed with assembly of the lower cover “H” as indicated
in gure 5-5.
Connections of pipes “A” and “G” on model 34 are 1” size,
however, at option of the installer the “A” adaptor can be
removed, changing the connection for 3/4”.
Couplings and raccords “A”, “B”, “C”, “D”, “E”, “F”, “G”, in
some models could be not supplied by factory.

18
MYDENS COSMOGAS
5.12 - Hydraulic connections
for model -- B boiler
The “B” version of the boiler must be connected to coil-type
indirect water heater for the production of domestic hot
water (see also section 5.16).
To do this, ttings have been set-up for connection to the
indirect water heater. Prepare as follows (refer to gure
5-7):
1.- t the reducer “A”;
2.- t the ducts “B” and “C”;
Make sure that every coupling has its own gasket.
Couplings and raccords “A”, “B” and “C” in some models
could be not supplied by factory.
A = reducer tting
B = supply to indirect water heater coil
C = return from indirect water heater coil
Figure 5-7 – Hydraulic connections for boiler with
indirect water heater with coil
5.13 - Polyphosphate
softener (on request)
If the boiler is installed in a geographical area where domestic
hot water has hardness exceeding 25°F (250 mg/l), a
polyphosphate softener must be installed on the cold water
supply (see gure 5-8, detail “B”), in order to safeguard the
appliance against limescale deposits.
Proceed as follows for installation (refer to gure 5-8):
1.- Connect the softener “B” to the cock “A”;
2.- Mount the cock “A” on the boiler tting;
3.- Proceed with the installation of the cold water inlet pipe
on the tting behind the softener “B”;
4.- Before retting the lower cover, trim the entire part
between walls “C” and “D”, from the outer edge to the
central slot (only in the rear part), to allow the softener
“B” to be housed.
Figure 5-8 – Polyphosphate softener
(on request)
A
B
C
020002.01.007
B
A
C
B
A
D
020002.01.008
5 - INSTALLATION

19 MYDENS
COSMOGAS
5.14 - Electrical connections: details
WARNING! The appliance is only electrically
safe when it has been correctly connected to an
efcient earth circuit, performed as provided for by the
current safety regulations.
This fundamental safety requirement must be met. If in
doubt, request a thorough check of the electrical system by
a professionally qualied technician.
Have a professionally qualied technician check that
the electrical system is suitable for the electric power
required by the appliance, as indicated on the plate.
The use of adapters, multiplugs, extension leads, etc. is
not permitted.
The appliance must be connected to the mains electricity
using a three-polar electric cable, with double isolation,
a minimum section of 1.5 mm² and resistance to a
minimum temperature of 70°C.
For connection to mains electricity, a bipolar switch must
be installed near the appliance with a contact opening
distance of at least 3 mm, as envisioned by the current
sector regulations.
Respect the polarity between the neutral and phase
wires when connecting the appliance.
Make sure that the water system and heating pipes
are not used as earth points for the electrical system
or telephone lines. This piping is not suitable for this
purpose; serious corrosion damage would occur in a very
short time to the appliance, piping and radiators.
WARNING! The boiler is not protected against
the effects caused by lightening.
5 - INSTALLATION
Figure 5-9 – Electrical connections
Figure 5-9 key
A = Control panel box;
B = Electrical connections board cover;
C = Connections cover closing aps;
D = Electrical connections board
Electrical contacts key
AL Slave = Slave appliance BUS;
CH = Cascade probe;
AD = Master appliance BUS;
TA = Room thermostat/ chronothermostat/ CR04 remote time
control/ Cosmobit
0-10 = 0-10 VDC communication;
SE = External sensor (where present);
SB = Indirect water heater sensor (where present);
MF = Alarm output/ Automatic ll;
EP = External pump (where present);
DNC = External diverter valve (where present) (D = Domestic
hot water line; N = Neutral; C = Heating line)
L1 = Boiler power supply line
N = Boiler power supply neutral
EARTH SYMBOL = Earth contacts
020002.01.010
62408190
AL
Slave CH
21 20 19 18 17 16 15 14 13 12 11 10 9 8 6 5 4 3 2 17
AD TA SE0-10 SB MF EP D N C
L1 N
C
D
CB
C
A
020025.01.009

20
MYDENS COSMOGAS
Figure 5-10 – Correct positioning of the room
thermostat/ chronothermostat
5.14.1 - Connecting the power supply
cable
Proceed as follows to connect the power supply cable (refer
to gure 5-9):
1.- Use a triple-pole dual-insulation cable, with a minimum
cross-section of 1.5 mm2;
2.- Remove the casing from the appliance, following the
relevant instructions in section 8.3;
3.- Rotate panel “A” towards the front of the boiler;
4.- Use the aps “C” and open the lid “B” as indicated by
the arrow;
5.- Lay the power supply cable through the fairlead near the
contacts “L1”, “N” and the earth symbol;
6.- Strip the cable, making sure that the earth wire (yellow/
green) is kept 20 mm longer than the other two;
7.- Connect the yellow/green cable to the earth terminal
(see symbol);
8.- Connect the brown cable (Phase) to terminal L1;
9.- Connect the blue cable (Neutral) to terminal N.
5.14.2 – Choosing the room thermostat/
chronothermostat
The boiler is set up to operate with any room thermostat
or chronothermostat which has the contact to which the
cables from the boiler can be connected, with the following
features:
- open/closed (ON/OFF);
- potential-free (not powered);
- closing, when there is a request for heat;
- 24VAC, 1A.
5 - INSTALLATION
1.0 1.5 2 3 4 5 6 7 8 9 10
OFF ON
Figure 5-11 – Operating rules for 0-10 VDC analogue input
Maximum
supply
temperature
(Par. 2111)
Minimum
supply
temperature
(Par. 2110)
ON/OFF
hysteresis