Embassy ONEX User manual

Installation and maintenance
instructions for gas-fired condensing
hot water boilers models:
ONEXONEX
ONEXONEX
ONEX
(Book No. 62403466, Ed. Sep. 2008)
INSTALLER, THESE INSTRUCTIONS TO BE AFFIXED ADJACENT TO THE BOILER.
ASME
certified
62403466 R04 14/11/2008

2
SAFETY INSTRUCTIONS
- Do not store or use gasoline or other
flammable vapors and liquids in the
vicinity of this or any other appliance.
- WHAT TO DO IF YOU SMELL GAS
• Do not try to light any appliance.
• Do not touch any electrical switch; do
not use any phone in your building.
• Immediately call your gas supplier from
a neighbor’s phone. Follow the gas
supplier’s instructions.
• If you cannot reach your gas supplier,
call the fire department.
- Installation and service must be
performed by a qualified installer, service
agency or the gas supplier.
- Ne pas entreposer ni utiliser d’essence ou
ni d’autres vapeurs ou liquides
inflammables à proximité de cette appareil
ou de tout autre appareil.
- QUE FAIRE SI VOUS SENTEZ UNE
ODEUR DE GAZ:
• Ne pas tenter d’allumer l’appareil.
• Ne touchez à aucun interrupteur, ne
pas vous servir des téléphones se
trouvant dans le bâtiment
• Appelez immédiatement votre
fournisseur de gas de puis un voisin.
Suivez les instructions du fournisseur.
• Si vous ne pouvez rejoindre le
fournisseur, appelez le service des
incendies
- L’installation et l’entretien doivent être
assurés par un installateur ou un service
d’entretien qualifié ou par le fournisseur
de gaz.
WARNING: If the information in these
instructions is not followed exactly, a fire
or explosion may result causing property
damage, personal injury or death.
AVERTISSMENT: Assurez vous de bien
suivre les instructions données dans
cette notice pour réduire au minimum le
risque d’incendie ou d’explosion ou pour
éviter tout dommage matériel, toute
blessure ou la mort

3
SAFETY INSTRUCTIONS

4
In the event of a breakdown and/or malfunction of
the boiler, turn off the unit and do not make any
attempt to repair it. The boiler must be serviced
exclusively by a qualified technician using original spare
parts. Failure to comply with this requirement may
compromise the safety of the unit and void its warranty.
Use the service switch to disconnect the boiler
from the electrical circuit before carrying out any
service or maintenance operations.
Electrical
CAUTION: Label all wires prior to disconnection when
servicing controls. Wiring errors can cause improper and
dangerous operation. Verify proper operation after
servicing.
ATTENTION: Au moment de l’entretien des
commandes, étiquetez tous les fils avant de les
débrancher. Des erreurs de câblage peuvent entraîner
un fonctionnement inadéquat et dangereux. S’assurer
que l’appareil fonctionne adéquatement une fois
l’entretirn terminé.
Correct Use:
This boiler must only be used for the purpose for which
it has been expressly designed: heating of water for
closed circuit systems for central heating and the
production of domestic hot water.
Should overheating occur or the gas supply fail
to shut off, do not turn off or disconnect the electrical
supply to the pump. Instead, shut off the gas supply at
a location external to the appliance.
En cas de surchauffe ou si l’alimentation de gaz
ne peut être coupée, ne pas couper ni débranch
l’alimentation électrique de la ponpe. Fermer plutôt le
robinet d’admission de gaz à l’extérieur de l’appareil
Do not use this appliance if any part has been
under water. Immediately call a qualified service
technician to inspect the appliance and to replace any
part of the control system and any gas control, which
has been under water.
N’utilisez pas cet appareil s’il a été plongé dans
l’eau, même partiellement. Faites inspecter l’appareil
par un tecnicien qualifié et remplacez toute partie du
système de contrôle et toute commande qui ont été
plongés dans l’eau.
Do not obstruct the air intake or vent pipe
terminals. Failure to take proper precautions can result
in excessive levels of carbon monoxide which can cause
severe personal injury or death!
Any optional extras or kit fitted subsequently
must be original Cosmogas spares.
SAFETY INSTRUCTIONS
WARNING!!! These instructions must be read prior
to installation. If the information in these
instructions is not followed exactly, a fire or
explosion may result, causing property damage,
personal injury, or death.
Liability
The manufacturer declines all liability, contractual or
otherwise, for damages resulting from the incorrect
installation of this boiler. This includes the failure to
comply with the instructions provided by the
manufacturer or from a failure to comply with the
applicable local and national regulations in force.
The manufacturer declines all liability, contractual or
otherwise, for any damage to people, animals or
property caused by the incorrect use of this boiler or
inadequate or incorrect service or maintenance.
Hazards and Your Safety - Hot Water Can Scald!
Water temperature over 125°F(52°C) can cause severe
burns instantly, or death from scalds. Children, the
disabled, and the elderly are at highest risk of being
scalded; see instruction manual before setting
temperature at boiler! Feel water before bathing or
showering.
If there is a smell of combustion products, turn the
unit off, air out the room and call a licensed authorized
technician. Failure to take proper precautions can
result in excessive levels of carbon monoxide which
can cause severe personal injury or death!
Qualified Technicians:
Qualified technicians are individuals with specific,
technical training in space heating systems, domestic
hot water systems, fuel gas systems and electrical
systems. These individuals must have the legally
required qualifications.
Installation and Alterations:
Licensed, authorized personnel must carry out the
installation and calibration of the boiler. Never modify the
boiler or its flue gas carrying components in any way.
This boiler must be properly vented. Failure to follow
these instructions could result in personal injury or
death!
For safety and environmental reasons, the packing
materials must be properly disposed of. Any replaced
part or packaging should never be left within the reach of
children. Failure to follow these instructions could result
in severe personal injury
Maintenance:
at least once a year the user must call in a licensed
authorized technician for routine maintenance.

5
TABLE OF CONTENTS
SAFETY INSTRUCTIONS ........................................................................................................................................................................ 2
TABLE OF CONTENTS ........................................................................................................................................................................... 5
1 - INSTALLATION - CODE REQUIREMENTS ......................................................................................................................................... 7
1.1 - National installation legislation ............................................................................................................................................... 7
2 - GENERAL INFORMATION .................................................................................................................................................................. 8
2.1 - Introduction .............................................................................................................................................................................. 8
2.2 - Manufacturer ............................................................................................................................................................................ 8
2.3 - Key to symbols used ............................................................................................................................................................... 8
2.4 - Description of models ............................................................................................................................................................. 8
3 - MAIN COMPONENTS ........................................................................................................................................................................ 9
4 - FUNCTION OVERVIEW ................................................................................................................................................................... 11
4.1 - Intended use and functions of the boiler ............................................................................................................................... 13
4.2 - Setting of the boiler ................................................................................................................................................................ 13
4.3 - A smart and intelligent boiler ................................................................................................................................................. 14
4.4 - Characteristic curves of heating system’s residual head .................................................................................................... 15
4.5 - Boiler head loss curve ........................................................................................................................................................... 15
4.6 - Characteristic curve of the domestic side ............................................................................................................................. 15
5 - INSTALLATION - Mounting & gas and water connections .......................................................................................................... 16
5.1 - Clearances for installation and servicing for models ........................................................................................................... 16
5.2 - Clearances from combustible material ................................................................................................................................ 16
5.3 - Choosing the installation location for 45WN and 45AN models .......................................................................................... 16
5.4 - Choosing the installation location for 45WE and 45AE models .......................................................................................... 17
5.5 - Mounting the boiler ................................................................................................................................................................ 18
5.5 - Mounting the casing in a 45WE or 45AE boiler ......................................................................................................... 18
5.6 - Gas and water connections .................................................................................................................................................. 18
5.7 - Condensate disposal ............................................................................................................................................................ 19
5.8 - Relief valve ............................................................................................................................................................................. 19
5.9 - Supply and return piping ....................................................................................................................................................... 20
5.10 - Low temperature heating systems ..................................................................................................................................... 20
5.11 - Use of glycol and other chemicals ...................................................................................................................................... 20
5.12 - Domestic hot and cold water (only for 45WN and 45WE models) ..................................................................................... 20
5.13 - Gas supply piping ................................................................................................................................................................ 21
5.14 - Operating at high altitudes .................................................................................................................................................. 21
5.15 - Suggested piping and wiring connections for the 45WN and 45WE versions Boiler ....................................................... 22
5.16 - Suggested piping and wiring connections for the 45AN and 45AE versions Boiler .......................................................... 23
6 - INSTALLATION - Electrical connections ....................................................................................................................................... 24
6.1 - Electrical connections: overview ........................................................................................................................................... 24
6.2 - Connecting the power supply cable ...................................................................................................................................... 25
6.3 - Choosing the room thermostat ............................................................................................................................................. 25
6.4 - Thermostat wiring .................................................................................................................................................................. 25
6.5 - Installing the outdoor temperature sensor (optional) ........................................................................................................... 26
6.6 - Wiring the circulator pump for 45AN and 45AE models ....................................................................................................... 26
6.7 - Alarm output ........................................................................................................................................................................... 26
6.8 - Installing the remote command on 45WE and 45AE models .............................................................................................. 27
7 - INSTALLATION - Indirect storage tank connections ................................................................................................................... 28
7.1 - Connecting the boiler to an indirect storage tank ................................................................................................................. 28
8 - INSTALLATION - Vent & combustion air ....................................................................................................................................... 30
8.1 - Removing of a boiler from a common venting system ......................................................................................................... 30
8.2 - Venting systems .................................................................................................................................................................... 31
8.3 - Design of the venting system ................................................................................................................................................ 31
9 - INSTALLATION - Split 80/80PP venting system............................................................................................................................ 32
9.1 - “Split 80/80PP” system (polypropylene) or AL29-4C (UL 1738/UL C 636) system .............................................................. 32
9.2 - “Split 80/80PP” system components ................................................................................................................................... 34
9.3 - “Split 80/80PP” system: installation examples ..................................................................................................................... 35
10 - INSTALLATION - Coaxial 60/100PP venting system .................................................................................................................. 36
10.1 - “Coaxial 60/100PP” polypropylene system ........................................................................................................................ 36
10.2 - “Coaxial 60/100 PP” system components .......................................................................................................................... 37
10.3 - “Coaxial 60/100PP” system: installation examples ......................................................................................................... 38
11 - OPERATING ................................................................................................................................................................................... 39
11.1 - Operating ............................................................................................................................................................................. 39
11.1.1 - User instructions ................................................................................................................................................... 39
11.1.2 - Filling the condensate trap .................................................................................................................................... 39

6
TABLE OF CONTENTS
11.1.3 - Filling the heating system ..................................................................................................................................... 39
11.1.4 - Filling of the domestic hot water heat exchanger (“45WN and 45WE” models only) .......................................... 39
11.1.5 – Auto-purging the heating system .......................................................................................................................... 39
11.2 - General warnings concerning gas supply .......................................................................................................................... 40
11.3 - Confirming the boiler’s gas type ......................................................................................................................................... 40
11.4 - Gas type conversion ............................................................................................................................................................ 40
11.5 - Start-up ................................................................................................................................................................................. 40
11.6 - Ignition control testing .......................................................................................................................................................... 40
11.7 - Gas supply pressure checking and adjustment ................................................................................................................. 41
11.8 - Check the combustion air pressure ................................................................................................................................... 42
11.9 - Checking and adjusting CO2 levels .................................................................................................................................... 43
11.9.1 - Checking and adjusting CO2 levels without CO2 meter ...................................................................................... 43
11.10 - Adjusting the heating capacity ........................................................................................................................................... 44
11.11 - Domestic hot water flow rate adjustment (45WN and 45WE models only) ..................................................................... 44
11.12 - Cold start boiler ................................................................................................................................................................. 44
12 - USE ............................................................................................................................................................................................... 45
12.1 - Adjusting the domestic hot water temperature .................................................................................................................. 45
12.2 - Heating system temperature adjustment ........................................................................................................................... 45
12.3 - Heating system type selection ............................................................................................................................................ 45
12.4 - Climatic adjustment ............................................................................................................................................................ 45
12.4.1 - Climatic adjustment: applicable system .............................................................................................................. 45
12.4.2 - Climatic adjustment precautions.......................................................................................................................... 45
12.4.3 - Climatic adjustment: setting parameters ............................................................................................................. 46
12.4.4 - Climatic adjustment: zone adjustments ............................................................................................................... 46
12.4.5 - Climatic adjustment activation .............................................................................................................................. 46
12.4.6 – Climatic adjustment with room compensation ................................................................................................... 46
12.5 - Boiler switch settings .......................................................................................................................................................... 48
12.6 - Delays, alarms and protective actions ................................................................................................................................ 48
12.7 - Circulator pump and three way valve protection ................................................................................................................. 48
12.8 - Freeze protection ................................................................................................................................................................. 48
12.9 - Display in energy saving mode ........................................................................................................................................... 48
12.10 - “Users’ menu” ................................................................................................................................................................... 49
12.11 - “Installers’ menu” .............................................................................................................................................................. 50
12.12 - Diagnostics ....................................................................................................................................................................... 52
12.12.1 - Diagnostics: “L” lock-outs ................................................................................................................................... 53
12.12.2 - Diagnostics: “E” blocking errors ......................................................................................................................... 55
12.13 - Remote command for model 45WE and 45AE ................................................................................................................ 57
13 - MAINTENANCE ............................................................................................................................................................................. 58
13.1 - General precaution .............................................................................................................................................................. 58
13.2 - Removing the casing for models 45WN and 45AN ............................................................................................................ 59
13.3 - Removing the casing on models 45WE and 45AE ............................................................................................................ 60
13.3.1 - Installing the casing on models 45WE and 45AE ................................................................................................ 60
13.4 - Cleaning the burner and primary heat exchanger, flue gas side ...................................................................................... 61
13.5 - Correct positioning of the ignition and flame detection electrodes .................................................................................... 62
13.6 - Domestic hot water heat exchanger (only for 45WN model ............................................................................................... 62
13.7 - Condensate trap cleaning ................................................................................................................................................... 63
13.8 - Circulator pump motor replacement (only for 45WN and 45WE models) ......................................................................... 64
13.9 - Expansion tank pressure (only for 45WN and 45WE models) ........................................................................................... 64
13.10 - 3-way valve removal (only for 45WN and 45WE models) ................................................................................................. 65
13.11 - Draining the heating side of the boiler .............................................................................................................................. 66
13.12 - Draining the domestic hot water side of the boiler ........................................................................................................... 66
13.13 – Overrides .......................................................................................................................................................................... 66
13.13.1 - Auto-purging ........................................................................................................................................................ 66
13.13.2 - Fan....................................................................................................................................................................... 66
13.13.3 – Minimum and maximum output ......................................................................................................................... 66
13.13.4 – Checking the flame current ................................................................................................................................ 66
13.14 - Water and flue temperature sensor .................................................................................................................................. 67
13.15 - Outdoor temperature sensor (optional) ............................................................................................................................ 67
13.16 - Functional wiring diagram ................................................................................................................................................. 68
13.17 - Multiwire wiring diagram ................................................................................................................................................... 69
14 - TECHNICAL DATA ......................................................................................................................................................................... 70
15 - SPARE PARTS .............................................................................................................................................................................. 71
16 - MENU’S FLOW CHART ................................................................................................................................................................. 76

7
1 - INSTALLATION - CODE REQUIREMENTS
1.1 - National
installation
legislation
- The installation must conform to the
requirements of the authority having
jurisdiction or, in the absence of such
requirements, to the latest edition of
the National Fuel Gas Code, ANSI
Z223.1/NFPA 54 and or CAN/CSA
B149.1, Natural Gas and Propane
Installation Code.
- Where required by the authority
having jurisdiction, the installation
must conform to the Standard for
Controls and Safety Devices for
Automatically Fired Boilers, ANSI/
ASME CSD-1

8
2 - GENERAL INFORMATION
2.1 - Introduction
Congratulations!
You have effectively purchased
one of the best boilers on the
market.
Each single part is built, tested and
assembled, with pride, at the
COSMOGAS factories, thereby
guaranteeing optimum quality
control.
Thanks to on-going research
carried out by COSMOGAS, this
product has been conceived and is
considered to be the best in its
class with regards to respect for
the environment. Great
importance is also given to the end
of the boiler’s useful life. All of its
components can easily be
separated into similar and
completely recyclable parts.
2.2 - Manufacturer
COSMOGAS srl
Via L. da Vinci 16
47014 - Meldola (FC)
ITALY
Tel. [phone]
Fax. [phone]
www.cosmogas.com
[email protected]
Spare parts are available from your
local authorized wholesale distributor.
For a location of the one nearest you
call 413 -564- 9538.
45
AN = heating only version, for inside installation
WN = combi version (space heating and instantaneous D.H.W.
production), for inside installation.
AE = heating only version, for outdoor installation
WE = combi version (space heating and instantaneous D.H.W.
production), for outdoor installation.
Modulating gas-fired, condensing hot water boiler, with sealed
combustion chamber and pre-mix burner, with maximum power input
of 160,000 Btu/hr (47 kW) and minimum of 30,000 Btu/hr (9 kW)
XX
2.3 - Key to
symbols used
WARNING!!! Failure to follow these
indications can causing an
explosion, extensive property
damage, severe personal injury or
death!
CAUTION!!!
Electrical caution! Risk of electric
shock: failure to observe this warning
may compromise the smooth running
of the appliance or cause serious
damage to individuals, animals or
property.
CAUTION!!!
General caution. Failure to observe this
warning may compromise the smooth
running of the appliance or cause
serious damage to individuals, animals
or property.
 Operation symbol
 Important indication symbol
2.4 - Description of
models

9
1 - Automatic air vent
2 - Air intake and flue gas discharge fitting (venting system)
3 - U7 flue gas temp. sensor and flue safety switch
4 - Expansion tank (not present on 45AN and 45AE models)
5 - Air drum
6 - Air/gas mixer device
7 - U2 d.h.w. temp. sensor (not present on 45AN and 45AE models)
8 - Heating pressure switch (low water cut-off)
9 - Heating supply connection
10 - DHW connection (not present on 45AN and 45AE models)
11 - Gas inlet connection
12 - DCW connection (not present on 45AN and 45AE models)
13 - Heating return connection
14 - Power Control Board
15 - Openterm interface board (optional)
16 - Connection board
17 - Primary heat exchanger
18 - Spark cable
19 - External jacket
20 - Sealing chamber door
21 - Instrument panel door
Figure 1 - Main components
3 - MAIN COMPONENTS

10
22 - Combustion analysis tap
23 - U1 supply temperature sensor
24 - Burner window
25 -Air/gas manifold
26 - U6 high temperature limit sensor
27 - Flue gases back flow preventer
28 - Fan
29 - Gas valve
30 - Heating pressure gauge
31 - Display
32 - Domestic hot water temperature control
33 - Heating temperature control
34 - On/off power switch
35 - Three way valve (not present on 45AN
and 45AE models)
36 - U3 domestic cold water temp. sensor (not
present on 45AN and 45AE models)
37 - Cable clamp
38 - ASME Safety relief valve
39 - U8 return temperature sensor
40 - By-pass pipe (not present on 45AN and
45AE models)
41 - Condensation discharge pipe
42 - Secondary heat exchanger for domestic hot
water production (not present on 45AN and
models)
43 - Expansion tank connection pipe (not
present on 45AN and 45AE models)
44 - Circulator pump screw (not present on
45AN and 45AE models)
45 - Circulator pump (not present on 45AN and
45AE models)
46 - Condensation discharge trap
47 - Detection electrode
48 - Burner
49 - Right ignition electrode
50 - Left ignition electrode
51 - Spark generator
52 - Flue pressure switch
Figure 1 - Main components
3 - MAIN COMPONENTS

11
Key to figure 2:
1 = boiler model 45WN or 45WE
2 = automatic air vent
3 = air intake
4 = flue gases discharge
5 = sealed combustion chamber
6 = expansion tank
7 = burner
8 = fan
9 = gas valve
10 = condensate discharge trap
11 = circulator pump
12 = 3-way valve
13 = secondary heat exchanger for d.h.w.
14 = pressure gauge
15 = by-pass valve
17 = safety relief valve
21 = condensate discharge pipe
22 = heating supply pipe
23 = domestic hot water outlet
24 = gas inlet
25 = cold water inlet
26 = heating return pipe
45 = U7 = flue gas temperature sensor
46 = U1 = boiler temperature sensor
47 = U6 = high limit temperature sensor
48 = U3 = domestic cold water sensor/storage tank sensor
49 = U2 = domestic hot water temperature sensor
50 = U8 = return temperature sensor
51 = flue pressure switch
Figure 2 - 45WN and 45WE Hydronic functional schematic
4 - FUNCTION OVERVIEW

12
Key to figure 3:
1 = boiler model 45AN or 45AE
2 = automatic air vent
3 = air intake
4 = flue gases discharge
5 = sealed combustion chamber
7 = burner
8 = fan
9 = gas valve
10 = condensate discharge trap
14 = pressure gauge
17 = safety relief valve
20 = safety relief valve discharge
21 = condensation discharge pipe
22 = heating supply pipe
24 = gas inlet
26 = heating return pipe
45 = U7 = flue gas temperature sensor and high limit safety
switch
46 = U1 = boiler temperature sensor
47 = U6 = high limit temperature sensor
50 = U8 = return temperature sensor
51 = flue pressure switch
Figure 3 - 45AN and 45AE Hydronic functional schematic
4 - FUNCTION OVERVIEW

13
4.1 - Intended use
and functions of
the boiler
This gas-fired condensing boiler, is
designed to be used for central heating
and producing domestic hot water.
The maximum output heat is always
guaranteed for the production of
domestic hot water since it is given
priority over space heating demands.
Follow the specific procedure in
section 12.1 for the adjustment of the
domestic hot water temperature.
Depending on the model choosen, the
following system types can be created:
- 45WN. Using this boiler model, a
system can be created for the
production of instantaneous domestic
hot water and a heating system with
heating elements functioning at
temperatures ranging between 68°F
(20°C) and 189°F (87°C).
The boiler can also function directly
with a radiant floor panel, see section
5.9.
When connecting the boiler to the
heating system the installer must
consider the head loss of the heating
system to verify that the boiler pump is
adequate. Pump curve is shown in
figure 5. The same verification need to
be done for the domestic installation,
see figure 7.
- 45AN. Using this boiler model, a
heating system with heating elements
functioning at temperatures ranging
between 68°F (20 ° C) and 187°F (87 ° C)
can be configured.
The boiler can also function directly
with a radiant floor panel, see section
5.9.
The 45AN model is not equipped with
the components required for the
production of domestic hot water. Also
not included is the expansion tank and
circulator pump, see figure 3.
To connect the boiler to the heating
system, the installer must consider the
loss of pressure generated by the
boiler (see figure 6), and choose a
pump capable of overcoming the head
loss of both the boiler and the heating
system.
4 - FUNCTION OVERVIEW
- 45WE. This boiler is equal to the
45WN model, but is intended for
outdoor installation.
- 45AE. This boiler is equal to the
45AN model, but is intended for
outdoor installation.
All models can be connected to an
indirect storage tank for the production
of domestic hot water, section 7.
All models can be connected to a
room thermostat, section 6.3 and 6.4.
Because boiler models 45WE and
45AE are usually installed outside the
building, they need to be connected to
a Remote Command, section 6.8.
An outdoor air temperature sensor can
also be connected to the boiler for
maximum fuel efficiency and comfort
(see section 6.5). In this configuration
the room thermostat will compensate
by adjusting the room temperature.
The room temperature compensation
can be of an ON /OFF type or two-
stage. For further information on the
Climatic heat adjustment, refer to
section 12.4.
The boiler must be connected to a
heating system and a domestic hot
water supply with compatible
specifications, performance and
power rating.
Before installation, thoroughly flush
the heating and plumbing systems
of any residue or impurities which
might compromise the smooth
running of the boiler.
Only boilers model 45WE and
45AE are designed for outdoor
installation. However also for these
boilers you need to choose a
sheltered place where it is
protected from atmospheric
elements including frost.
Refer to figure 8 for minimum
clearance distances for installation
and future maintenance.
Refer to section 5.2 for minimum
clearance distances from
combustible material.
4.2 - Setting of the
boiler
Inside this instruction manual there are
sections that require you to change the
settings of the boiler. To do this, the
installer needs to operate on several
available menus, which are explained
within the section the change is
needed.
To aid the installer, all menus are also
shown in section 16 with an
explanation of which varies keys to
press.

14
4.3 - A smart and
intelligent boiler
When connected to an outside sensor
(optional), this boiler is designed to
always work at the maximum
efficiency. It will automatically change
the supply temperature in relation with
the outdoor temperature.
The graph in figure 4 shows an
example on how it can work.
This graph represent an installation
where the supply and return
temperatures are 139°F and 115°F
respectively , and the outside
temperature is 23°F. The outdoor
sensor drives the boiler, to
progressively reduce the supply
temperature and thereby optimize the
efficiency. It changes from 87% when
outside is -10°F, to 94.8% when
outside is 23°F and up to 98% when
the outside temperature rises up to
67°F.
Figure 4 - Relation between outdoor temperature, heating
temperature and efficiency
4 - FUNCTION OVERVIEW

15
4.4 - Characteristic
curves of heating
system’s residual
head
45WN and 45WE boilers are fitted with
its own specific circulator pump. The
residual head at the boiler connections
is shown in graph form in figure 5.
4.5 - Boiler head
loss curve
45AN and 45AE boilers are not fitted
with an internal pump. The installer
needs to install an external pump as
illustrated in figure 17, item “6”. Use
the graph in figure 6 to choose the
correct pump.
4.6 - Characteristic
curve of the
domestic side
45WN and 45WE boilers, offers certain
resistance to the passage of the
domestic water (see graph flow/
pressure of figure 7). The installer or
the engineer must take account of this
in order to ensure the correct domestic
water flow to the utilities.
Figure 5 - Residual Head for heating circuit for models “45WN”
and “45WE”
Figure 6 - Boiler Head Loss for models “45AN” and “45AE”
Figure 7 - Domestic Water Coil Head Loss for models “45WN”
and “45WE”
4 - FUNCTION OVERVIEW

16
5.1 - Clearances for
installation and servicing
for models
Figure 8 shows the clearances required for installation and
servicing.
NOTE: Service clearances are not mandatory, but are
recommended to ensure ease of service should it be
required.
5.2 - Clearances from
combustible material
This boiler may be installed directly onto a wall of
combustible material with the following clearance:
Ceiling: 2 inches (51 mm)
Front: 2 inches (51 mm)
Rear: 0 inches (0 mm)
Sides: 2 inches (51 mm)
Floor: 2 inches (51 mm)
Concentric vent: 0 inches (0 mm)
Split vent (first 12” from the boiler): 1 inch (25 mm)
Split vent (after 12” from the boiler): 0 inches (0 mm)
5.3 - Choosing the
installation location for
45WN and 45AN models
CAUTION!!! The boiler must be installed on a
vertical wall constructed to bear its weight or the
boiler and building may be damaged.
NOTE: The boiler must never be installed on
carpeting.
CAUTION!!! This boiler is not designed for
direct outdoor installation. If installed outside of the
structure that it supplies hot water too, it must be
sheltered so it is protected from rain, wind, sun and
frost. NEVER place this boiler in a location that would
subject it to temperatures at or near freezing. Failure
to properly locate this boiler can result in premature
failure voiding the warranty.
When locating the boiler the following factors must be
considered:
• the location of vent/air intake terminals;
• connection to the gas supply;
• connection to the water supply;
• connection to the heating system;
• connection to the domestic hot water system;
• connection to the electrical supply;
• disposal of the condensation produced by the boiler;
• connection to the room thermostat;
• piping of the safety relief valve discharge;
• possible connection of the outdoor temperature sensor;
• possible connection of an indirect storage tank, see
section 7.
Figure 8 - Recommended minimum clearance
distances for proper installation and servicing for
models 45WN, 45AN, 45AE and 45WE.
1 = Area for power supply cable
2 = Heating supply connection (3/4”)
3 = Domestic hot water connection (3/4”)
(absent in 45AN model)
4 = Gas connection (3/4”)
5 = Domestic cold water connection (3/4”) (absent in
45AN model)
6 = heating return connection (3/4”)
7 = positions for boiler support
8 = Flue discharge/air intake connection
Figure 9 - Dimensions for models 45WN and 45AN
5 - INSTALLATION - Mounting & gas and water connections

17
1 = Area for power supply cable
2 = Heating supply connection (3/4”)
3 = Domestic hot water connection (3/4”)
(absent in 45AE model)
4 = Gas connection (3/4”)
5 = Domestic cold water connection (3/4”) (absent in
45AE model)
6 = heating return connection (3/4”)
7 = positions for boiler support
8 = Flue discharge/air intake connection
Figure 10 - Dimensions for models 45WE and 45AE
5.4 - Choosing the
installation location for
45WE and 45AE models
CAUTION!!! The boiler must be installed on a
vertical wall constructed to bear its weight or the
boiler and building may be damaged.
NOTE: The boiler must never be installed on
carpeting.
CAUTION!!! This boiler is designed also for
direct outdoor installation. However, if installed
outside of the structure that it supplies hot water too,
it must be sheltered so it is protected from rain, sun
and frost. NEVER place this boiler in a location that
would subject it to temperatures at or near freezing.
Failure to properly locate this boiler can result in
premature failure voiding the warranty.
When locating the boiler the following factors must be
considered:
• the location of vent/air intake terminals;
• connection to the gas supply;
• connection to the water supply;
• connection to the heating system;
• connection to the domestic hot water system;
• connection to the electrical supply;
• disposal of the condensation produced by the boiler;
• connection to the room thermostat;
• connection to the remote command;
• piping of the safety relief valve discharge;
• possible connection of the outdoor temperature sensor;
• possible connection of an indirect storage tank, see
section 7.
5 - INSTALLATION - Mounting & gas and water connections

18
5 - INSTALLATION - Mounting & gas and water connections
5.5 - Mounting the boiler
Refer to figure 11:
place the cardboard template, provided with the
boiler, against the wall;
ensure that the template is plumb and the screw
holes line up with the wall studs;
CAUTION!!! The wall bracket screws
must be screwed into the buildings framing or
other material capable of supporting the
weight of the boiler or the boiler and building
may be damaged.
mark the screw holes for the wall bracket, “A”;
remove the cardboard template;
install the wall bracket “A”, using the screws “E”,
provided;
hang the boiler on the wall bracket, “A”, by
hanging connections “B” and “C” on tabs “D”.
5.5 - Mounting the plastic
cover on a 45WE or 45AE
boiler
If you are installing a 45WE or 45AE boiler for
outside use, you must also install the plastic outer
jacket cover as per section 13.3.1. The plastic
cover will need to be cut on the bottom to adapt the
passage of:
- the gas and water connections as per section
5.6;
- the condensate drain as per section 5.7;
- the relief valve discharge, as per section 5.8.
5.6 - Gas and water
connections
The boiler comes with the fittings shown in figure
12.
Figure 12 - Fittings supplied with the boiler
Figure 11 - Wall bracket installation
A = heating system supply (3/4”)
B = domestic hot water supply (3/4”) (Absent on
45AN and 45AE models)
C = Inlet gas connection (3/4”)
D = domestic cold water (3/4”) (Absent on 45AN
and 45AE models)
E = heating system return (3/4”)

19
5 - INSTALLATION - Mounting & gas and water connections
A = 3/4” pipe extension (not provided)
B = Discharge device with connection to
the atmosphere pressure (not provided)
C = Condensate discharge pipe
Figure 13 - Relief valve connection
5.7 - Condensate
disposal
WARNING! The condensate trap
must be connected to the boiler per
the following instructions or
combustion gases will enter the
room. This can result in excessive
levels of carbon monoxide which
can cause severe personal injury or
death!
This boiler produces water as a
byproduct of combustion. The boiler is
equipped with a condensate trap, figure
1, item 46, for the evacuation of
condensate and to prevent the leakage
of combustion products. The
condensate trap drains through pipe
“C” shown in Figure 13. The
condensation disposal system must:
be connected to the domestic
waste disposal system by means of
an appropriate trap capable of
preventing the pressurization of the
condensate system and the return
of sewer gases (see figure 14);
comply with national and/or local
codes for condensate neutralizer
between pipe “C” of figure 13 and the
waste disposal system;
be carried out with a pipe with an
internal diameter equal to or greater
than 1/2 in, 13 mm;
be installed in such a way so as to
avoid the freezing of the liquid;
never discharge into gutters or rain
collectors;
properly pitched towards the point
of discharge avoiding high points,
which could place the condensate
system under pressure;
CAUTION!!! The condensate
drainage system is designed to
empty all the condensate produced
by one boiler only. Each boiler
must be equipped with its own
condensate drainage system or the
drainage system may malfunction.
5.8 - Relief valve
Each boiler is equipped with a safety
relief valve set at 30 psi (2 bar) which
must be piped in accordance with the
ANSI/ASME Boiler and Pressure
Vessel Code, Section IV, to prevent
scalding in the event of a discharge,
see Figures 1, item “38” and figure 13.
WARNING!!! Failure to properly
pipe the relief valve discharge can
result in scalding of individuals and
animals. Never install any type of
valve between the boiler and the
relief valve or an explosion
causing extensive property
damage, severe personal injury or
death may occur!
Figure 14 - Condensate trap e drain

20
5.9 - Supply and
return piping
CAUTION!!! All heating
system piping must be installed in
accordance with the ANSI/ASME
Boiler and Pressure Vessel Code,
Section IV. All applicable local
codes and ordinances must also be
followed. If the boiler is installed
above any radiation elements it
must be fitted with a low water
cutoff device installed above the
normal boiler water level! Failure
to do this can result in damage the
unit and void the warranty!
CAUTION!!! This boiler must
have adequate water flowing
through it whenever the burner is
on. Failure to do this will damage
the unit and void the warranty!
CAUTION!!! Before
connecting the boiler to the
heating system the heating system
must be thoroughly flushed to
remove sediment, flux, filings and
other foreign matter. An approved
inhibitor should be added to the
heating system water to prevent
limestone and magnetite deposits
from forming and to protect the
boiler from galvanic corrosion.
CAUTION!!! This boiler is
equipped with an ASME safety
relief valve set at 30 psi (2 bar). The
heating system must be designed
so that no piping or radiation
elements are higher than 65 ft (20
m) or else the hydraulic head of the
system will cause the relief valve to
open.
CAUTION!!! The
manufacturer cannot be held
responsible for any damage caused
by incorrect use of additives in the
heating system.
Figure 12 illustrates the position of
the supply and return pipes.
Install a metallic mesh filter on the
return pipe to prevent any residue
from the system returning to the
boiler.
Do not use the appliance for adding
any type of additive to the system.
5.10 - Low
temperature
heating systems
CAUTION!!! When the boiler
is installed in a low temperature
system, the switch “6” in figure 22
must be placed in the ON position
to prevent the supply water
temperature from exceeding 113°F
(45°C) or damage to the low
temperature system components
could occur (see section 5.9).
With switch “6” in figure 22, in the ON
position, the boiler will maintain the
supply water temperature between
68°F (20°C) and 113°F (45°C). No
setting changes made from the control
panel will cause the supply water
temperature to exceed 113°F (45°C).
CAUTION!!! If the boiler is
installed in a radiant panel heating
system using plastic piping,
precautions must be taken against
corrosion caused by water
oxygenation. If the piping does not
comply with these specifications,
the radiant panel circuit must be
isolated from the boiler using a
titanium plate heat exchanger.
5.11 - Use of glycol
and other
chemicals
WARNING!!! Never use non-
approved additives or toxic boiler
treatment chemicals in the heating
system as they can cause serious
health problems or possibly death.
Any additives introduced into the
heating system must be recognized
as safe by the United States Food
and Drug Administration.
If glycol is used, it must be used in
accordance with the instructions
supplied with the product.
CAUTION!!! Any additives
added to the heating system must
not be added directly inside the
boiler but through the heating
system piping to prevent damage
to the boiler.
5.12 - Domestic hot
and cold water
(only for 45WN and
45WE models)
CAUTION!!! If the water
hardness is greater than 9 gr/gal
(150 mg/l) we recommend installing
a water softener with filter.
Figure 12 illustrates the positioning
of the domestic hot and cold water
pipes.
For servicing purposes, install an
isolation valve upstream from the
cold water inlet.
For correctly set the domestic
water flow, install an adjustable
flow restrictor upstream the cold
water inlet (see figure 16 item “12”)
45WN and 45WE boilers can work
also like a only heating boilers,
simply avoid to connect the
domestic pipes “B” and “D” of figure
12.
5 - INSTALLATION - Mounting & gas and water connections