COSMOGAS AXIA 20E User manual

Instruction manual for installation, use and maintenance
62403278 - R04 aug. 30-2002
MODELS:
AXIA 20E & AXIA 29E

2
SAFETY INSTRUCTIONS
WARNING:Iftheinformationinthese
instructionsisnotfollowed exactly,afire
orexplosionmayresultcausingproperty
damage,personalinjuryordeath.
— Do not store or use gasoline or other
flammablevaporsandliquidsinthe vicinity
ofthis or any other appliance.
— WHATTODOIFYOU SMELL GAS
• Do not try to light any appliance.
• Donot touch any electrical switch;do
notuseany phone in your building.
• Immediatelycallyour gas supplierfroma
neighbor’sphone.Followthegas
supplier’sinstructions.
• Ifyou cannot reach your gas supplier,
callthefiredepartment.
— Installationandservice must be
performedbya qualified installer,service
agencyorthe gas supplier.

3
- 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,personalinjury,or death.
- Hazards and Your Safety - Hot Water Can
Scald!Watertemperature over 125°F (52°C)
cancause severe burns instantly,or death
fromscalds. Children,disabled, andelderly
are at highest risk of being scalded; see
instructionmanual before settingtemperature
atwater heater! Feelwater beforebathing or
showering. Temperaturelimitingvalves are
available,seemanual.
- If there is a smell of gas: Turn the gas cock
off - Air the room - Do not try to light any
appliances - Do not use any phone in your
building - Do not touch any electrical switch -
Extinguish any flames - Call immediately a
licensedauthorized technician or your local
gas company - Follow the gas supplier’s
instructions - If you cannot reach your gas
supplier, call the firedepartment.
- If there is a smell of combustion products:
turn the unit off - Air the room - Call a licensed
authorizedtechnician.
- Installation, alterations: licensedauthorized
personnel must carry out the installation,
calibrationor alterationof thegas apparatus.
Flue gas ducts must not be modified in any
way. Any replaced part or packaging parts
shouldnever beleft within reach of children.
- Explosive products or easily inflammable
products:do not keep, use orstore explosive
materialsor easily inflammablematerials such
asGasoline, Adhesives,Solvents, Paint
Thinner,Butane,Liquefied Propane,paper,
etc., in the same room as the heater.
- Maintenance: the user, according to the
heater’s operating instructions, has to keep
theinstallation in good condition and
guaranteethe reliable, safeoperation ofthe
heater. At least once a year the user must
call in a licensed authorized technician for
routinemaintenance, beforeusing itfor central
heating.
- Servicing Manual: when the installation and
commissioning of the system has been
completed, the installer should instruct the
SAFETY INSTRUCTIONS
homeownerto save theinstallation manual
nearthe heater sothat service technicians
may refer to it in the future.
- Label all wires prior to disconnection when
servicing controls. Wiring errors can cause
improperanddangerous operation. Verify
properoperationafterservicing.
- Do not use this appliance if any part has
beenunder water. Immediately call a qualified
servicetechnician to inspectthe appliance and
to replace any part of the control system and
anygas control, which has beenunder water.
-In the eventof abreakdown and/ormalfunction
of the heater, turn off the unit and do not make
any attempt to repair it. The heater must be
servicedexclusively bya qualifiedtechnician.
If it is necessary to replace any components,
always use original spare parts. Failure to
comply with this requirement may compromise
the safety of the unit.
- This water heater must only be used for the
purpose for which it has been expressly
designed:heating ofwater for closed circuit
systems for the central heating of civil and
domesticbuildings, production of domestic
andsanitary hot water forcivil use.
-The manufacturer declines allliability,
contractualor otherwise,for damages resulting
fromincorrect installationor use of the heater,
or from failure to comply with the instructions
providedbythe manufacturer, or fromnon
compliancewith the applicable local and
nationalregulations in force.
-For safetyand environmental reasons, the
packing materials must be disposed of at the
appropriatesorted refusecollection centres.
-Should overheatingoccur or the gas supplyfail
toshut off,turn off the gas valveservice switch
tothe heater.

4
TABLE OF CONTENTS
1 - GENERAL INFORMATION................................................................ 6
1.1-Key to the symbols used........................................................................................... 6
1.2-Warranty .................................................................................................................. 6
2 - GENERAL LAYOUT of the main components................................ 7
3 - INSTALLATION ................................................................................. 8
3.1- Pre-Installation ......................................................................................................... 8
3.2- Instructionsfor theuser............................................................................................. 8
3.3- Clearances for installation ........................................................................................ 8
3.4-Clearances from combustible material ..................................................................... 8
3.5-Choosing the place of installation ............................................................................. 8
3.6-Preparing to install thewaterheater.......................................................................... 9
3.7- InstallationTemplate ................................................................................................. 9
3.8- Supplyand ReturnPiping ....................................................................................... 10
3.9- RadiantHeatingInstallation .................................................................................... 10
3.10- Installationoftwo heaters ..................................................................................... 10
3.11 - Installationof threeormore heaters ...................................................................... 10
3.12- Multi-zonesystemwith severalpumps .................................................................. 10
3.13 -Multi-zone System ................................................................................................ 10
3.14- Internalelectricalconnection settings.................................................................... 10
3.15-Use of glycol ........................................................................................................ 10
3.16 - Domestic Hot and Cold water .............................................................................. 10
3.17-WaterHardness ................................................................................................... 11
3.18- Gas supply ........................................................................................................... 11
3.19-Operating at high altitudes.................................................................................... 11
3.20- Connecting thesupply, return,gas,cold water andhotwater................................. 12
3.21- Safety reliefvalve ................................................................................................. 12
3.22-Electrical connections .......................................................................................... 13
3.22.1- Overview .................................................................................................. 13
3.22.2 - Choosingthe room thermostat .................................................................. 13
3.22.3- Connecting theroomthermostat ............................................................... 13
3.22.4- Connecting the powersupplycable........................................................... 14
3.22.5-Functional electrical diagram .................................................................... 15
3.22.6-Multiwire electric diagram ......................................................................... 16
3.23- Ventingsystems................................................................................................... 17
3.23.1-Rotation of the fluedischarge/airintakefittings.......................................... 18
3.23.2-Kitforairintake/fluedischarge.................................................................. 19
3.23.3-80/80split system..................................................................................... 20
3.23.4 - 80/80 split system: available accessories ................................................. 21
3.23.5- 80/80 split system:installationexamples................................................... 22
3.23.6-60/100coaxial system .............................................................................. 23
3.23.7-60/100 coaxial system: available accessories .......................................... 25
3.23.8 -60/100 coaxialsystem: installationexamples ............................................ 26
3.23.9 - Combustion air supplied from inside......................................................... 27
3.23.10-Removing the condensationproducedbyflue gas discharge .................. 28
3.24-WaterConnections............................................................................................... 29
3.25- Filling the heatingsystem ..................................................................................... 40
3.26- Ignition .................................................................................................................40
3.27- Regulating the domestichotwater........................................................................ 40
3.28-Disassembling the cover panels........................................................................... 41

5
TABLE OF CONTENTS
3.29- Accessing the internalcomponents ...................................................................... 41
3.30-Converting the burner tousea different type of gas .............................................. 42
3.31-Checking and adjusting thepressureof the gas supply......................................... 42
3.32-Checking and adjusting thegaspressure at the burner......................................... 43
3.33- Check CO2 level .................................................................................................. 43
3.34-Adjusting the input ratingtothe required heat loss ................................................ 44
3.35- Adjust theinputrating to the requiredmaximumefficiency .................................... 44
4 - MAINTENANCE ............................................................................... 45
4.1 -General cautions .................................................................................................... 45
4.2- Cleaning theburnerand the heatexchanger (flue-gasside) ................................... 45
4.3- Burner flame .......................................................................................................... 46
4.4- Safety reliefvalves ................................................................................................. 46
4.5 - Flue gas discharge ................................................................................................ 46
4.6 -Combustible material ............................................................................................. 46
4.7-Draining the heating side of the heater ................................................................... 46
4.8 - Draining the domestic side of the heater ................................................................ 46
5 - USE.................................................................................................. 47
5.1- Control panel.......................................................................................................... 48
5.2- Ignition procedure .................................................................................................. 48
5.3-Summer operation ................................................................................................. 48
5.4-Winter operation .................................................................................................... 48
5.5- Adjustments forwinteroperation ............................................................................ 49
5.6- Room thermostat ................................................................................................... 49
5.7- ResettingtheIgnition Module.................................................................................. 49
5.8-Low water cut-off device......................................................................................... 49
5.9- ManualResetHigh-Limit Thermostat...................................................................... 49
5.10-Heating Circulator Pump ...................................................................................... 49
5.11 -Temperature-Pressuregauge............................................................................... 49
5.12- Gas valve serviceswitch ...................................................................................... 49
5.13- Shut-off procedure ............................................................................................... 49
5.14-Precautions againstfreezing ................................................................................ 50
5.15 - Flue gas discharge .............................................................................................. 50
5.16-Abnormalities during operation ............................................................................ 50
6 - TROUBLESHOOTING .................................................................... 51
6.1-TroubleshootingSequenceof operation tolightthe burner ...................................... 51
6.2-Troubleshooting SequenceofOperationfor a CallforHeat..................................... 52
6.3-Troubleshooting SequenceofOperation for a CallforD.H.W. ................................. 52
7 - SPARE PARTS ................................................................................ 53
8 - TECHNICAL DATA .......................................................................... 54
8.1-Tableof the technical data ...................................................................................... 54
8.2- Curves of residualheadfor central heatingsystem ................................................. 55
8.3-Curvesburnerpressure-inputrating........................................................................ 55
8.4- CurvesEfficiency-inputrating ................................................................................. 55

6
Thisinstructionmanualrefers
totwo types ofheaters:
AXIA 20E - this appliance
isa wall mounted,directvent
modulatingspace/water
heaterwith inputpowerrating
from51,180Btu/hr (15 kW) to
90,000Btu/hr (26.4 kW)
AXIA 29E - this appliance
isa wall mounted,directvent
modulatingspace/water
heaterwith inputpowerrating
from99,000Btu/hr (29 kW) to
157,000Btu/hr(46 kW)
1 - GENERAL INFORMATION
1.1 - Key to the symbols used
CAUTION!!!electrical shock!
Failureto observethese precautions may compromise thecorrect
operation of the apliance or cause serious injury to persons or
animals,or damageto property.
CAUTION!!! Generic danger ! Failureto observethese
precautionsmay compromise the correct operation of theunit or
cause serious injury to persons or animals, or damage to property.
lCAUTION!!!
Importantor necessaryactivity
1.2 - Warranty
Referto theenclosed warrantycard.
Whenreferring to this
instructionmanual, besure of
whichtype ofheateryou are
workingwith. This canbe
verifiedby referring to the
data plate marked “Space
waterheater model” .This
data plate is located on the
bottomsideof the heater.
Alsoverify thetype of gas for
whichtheheater is set. A
labelin thefrontof yourheater
states “NATURALGAS”, for
heatersset to natural gas,or
“LP GAS” for heaters set to
LP gas.

7
1 Connection for air intake in split system
2 Connection for coaxial pipe or for flue
discharge in split system
3 Automatic air vent
4 Expansion tank
5 Gas valve
6 Safety relief valve
7 Circulator pump
8 Heat exchanger
9 Ignition module
10 Speed control board
11 Domestic hot water priority thermostat
12 Domestic hot water pipe
13 Domestic cold water pipe
2 - GENERAL LAYOUT of the main components
Figure1 - Generallayoutof the maincomponents
14 Frame
15 Temperature-pressure gauge
16 Multifunction selector
17 Blower
18 Heater temperature control
20 High limit thermostat
21 Gas valve service switch
22 Junction box
23 Electrical control board
24 Cold start thermostat (optional)

8
3.1 - Pre-
Installation
Installation must conform to the
requirementsofthe authorityhaving
jurisdiction. In the absence of such
requirements,installation must
conformto:
National Fuel Gas Code ANSI
Z223.1/NFPA 54 and or CSA
B149.1,Natural Gas and
PropaneInstallation Code.
Thisappliance isdesigned for
heatingwater to a temperature
below its boiling point at
atmosphericpressure.
-It must be hooked up to a
heating system and to a sanitary
hot water distribution system
compatiblewith the
characteristics,performance and
powerratings of the water heater
itself.
-Before installation it is
necessaryto thoroughlyflush
theheating and plumbing
systems, in order to remove any
residues or impurities which may
compromisethe correct
functioningof thewater heater.
-This water heater is not suitable
foroutside installation unless an
outside installation kit is
installed with the heater. .
Choose a place that is protected
fromthe atmosphericelements
i.e. rain, wind, sun and
especially frost, and which
complieswith therequirements
prescribedby theapplicable
nationaland/or local regulations.
-Referto figure4 forthe minimum
clearancedistances required for
installationand subsequent
servicing.
3.2 - Instructions
for the user
The installer must instruct the user
on the correct use of the water
heater , and in particular must:
lsupply the installation and user
manualand all the
documentationcontained inthe
packingmaterials;
linstruct the user concerning the
special measures to be taken for
thedischarge of flue gases, and
inform the user that these must
notbe altered;
linform the user concerning the
3 - INSTALLATION
controlof thewater pressure
necessary in the system and the
necessarymeasures forfilling
andforpurging;
linform the user on how to
correctly set the temperatures
androom thermostats to
conserveenergy.
3.3 - Clearances
for installation
Figure4 showsthe proper
distancesthat are allowed for the
supportbracket and wall. (see
figure2)
3.4 - Clearances
from combustible
material
Thisappliance may be installed
directly onto a wall of combustible
materialwith the following
clearance:
Ceiling 8 inches
Front 2 inches
Rear 0 inches
Sides 2 inches
Floor 8 inches
3.5 - Choosing
the place of
installation
CAUTION!!!Thewater
heater must be installed on a
vertical wall that is able to support
its weight.
Heater may also be installed in a
closetor alcove.
Choosea location centralized to
the piping system with
considerationto thevent pipe
length. You will need to place the
space/water heater so that the
controls, drain, inlet/outlet, and gas
valveare easilyaccessed. Care
mustbe exercised whenchoosing
the location of this appliance,
whereleakage from thesafety relief
valves,leakagefromrelated piping,
or connections, will not result in
damageto the surroundingareas,
orto the lower floor ofthe building.
Nothingshould beinstalled
betweenthesafety reliefvalvesand
theheater. The dischargefrom the
pressurereliefvalve must be
connected to a suitable place for
disposal. Noreducing, coupling or
other restrictions shall be installed
in the discharge line. The
dischargeline shouldallow
completedrainageofboth valve and
line.
Choosea suitableroom and
position for installation, taking the
followingfactors intoaccount:
-connectionof the flue gas
discharge/airintake pipes;
-connection of the gas supply
piping;
-connectionof the water supply;
connectionof thecentral heating
system;
-connection of the sanitary hot
water system;
-electricalconnections;
-possibleconnection for draining
thecondensation produced by
the flue gas discharge system;
- possibledischarge connection for
thesafetyrelief valve.

9
3.6 - Preparing to
install the water
heater
lTake the support bracket (see figure 2)
andchoose aposition with proper
clearances, as per Figure 4.
CAUTION!!! Whenchoosinga
mountingsurface forthe heater. The
weight of the heater with water is
approximately 150 lbs (68 kg). Make
certain that the wall can support such
weight.
lSecure the bracket to the wall. NOTE:
Screws MUST be screwed directly into
the 16" (406 mm) vertical studs
lPlace the template onto the support
bracket and make necessary hole or
holesfor thedischarge fluevent. (see
also chapters on venting systems).
lInstall the heater on the support bracket
and secure all of the connections.
3.7 - Installation
Template
The heateris providedwith aninstallation
templateto facilitateproper installation
alignments(See figure 3).
3 - INSTALLATION
Figure 2 - Support bracket
Figure3 -Installationtemplate

10
3.8 - Supply and
Return Piping
Thecentralheatingsupplyandreturn
pipes are marked with different
coloredcaps, (supplyred and return
blue).
Ifthe heateris to be connected toan
existing system it is advisable to
wash out and remove any deposits
from inside the existing pipes, and
install a filter at the lowest point to
trapanyadditional impuritieswhenit
isrunning.
This equipment is designed for use
in a closed loop system.
The pressure of the heating system
sideof theheater must be fitted with
devices (automatic water feed/
pressurereducingvalvenottoexceed
30 psi (2 bar)) adapted to function
automaticallyinordertomaintain the
pressureoftheheatingsideatalevel
belowthatofthepotablewaterleaving
theheat exchanger.
Installation schematics are found in
figures26 to 40.
CAUTION!!! All the
schematics in figures 26 to 40 are
onlysamples.Safetyapparatus,pipe
diameters,andauxiliaryaccessories
must be verified by qualified
personnelandinaccordancewiththe
nationaland/or localcodes.
3.9 - Radiant
Heating
Installation
When the heater is used in
conjuction with radiant heating, it is
imperativethatthetubingcontainsan
oxygen diffusion barrier. If you are
unsurewhetheror not thetubinghas
abarrier, astainlesssteel plate heat
exchanger must be used to protect
the heater from oxygen corrosion
(Seefigure30).Oxygencorrosionwill
also occur if the heater is used in an
open-loop system where new, cold-
fill water is introduced into the
system.Theoxygenwillremoveitself
from solution and react chemically
with the ferrous components (i.e.
steel), causing them to rust and
corrode.THISTYPE OF FAILUREIS
NOT COVERED BY THE
WARRANTY!
3.10 - Installation
of two heaters
To install two heaters in parallel,
followthe diagramin figure 28.
3.11 - Installation
of three or more
heaters
Installing three or more heaters in
parallel.Follow the diagramin figure
29.
3.12 - Multi-zone
system with
several pumps
When creating a multi-zone system
with pump servicing the zone, it is
necessary to isolate the operating
pressure of the water heater circuit
from the pressure of the heating
system circuit. For this purpose,
install a hydraulic disconnector
between the heater and the system
(seefig. 31)
3.13 - Multi-zone
System
When creating a multi-zone system
it is necessary to follow the diagram
shownin figure32.
3.14 - Internal
electrical
connection
settings
Thewaterheatercomes with asetof
electrical terminals for a variety of
system configurations, (inside
junctionbox):
-relaysfor severalpumps; the water
heater is provided with terminals for
connecting a relay that controls
severalpumpsatthesametime (see
figure35)
- plate heat exchanger; the water
heater is provided with terminals for
connecting and controlling a plate
3 - INSTALLATION
heatexchanger forthe production of
domestichotwaterorforaswimming
pool(seefigure 36)
- Indirect water heater; the heater is
providedwithterminalsforconnecting
and controlling an indirect water
heater (see figure 33) This function
canalso be combined with the relay
function for multiple pumps (see
figure34)
-Cold start boiler;inside thejunction
box there are two terminals (see
figure7) markedwith thenumbers 5
and 6, connected together by a
jumper. Simply remove this jumper
toenable the heater to also function
as a cold start boiler.
3.15 - Use of
glycol
Toxicchemicals,such as thoseused
for boiler treatment, shall not be
introduced into the potable water
usedfor spaceheating.
CAUTION!!! If a non-
approved additive is used, it can
cause serious health problems or
possibly death.
If glycol is used with the heater, the
glycol must be recognized as safe
or approved by the United States
FoodandDrugAdministrationforfood
contact as listed in Code of Federal
Regulations, title 21, part 182 of the
Food Additive Regulations. Any
additivesintroduced into theheating
systemmust be recognizedas safe
bythe UnitedStates Food and Drug
Administration.
If glycol is used, it must be used in
compliance with the product
instructions. In any case, such
substances should not be added
directly inside the heater, but only
througharadiator.
3.16 - Domestic
Hot and Cold
water
The domestic hot water flow restrictor
mustbeinstalledonthecoldwaterinlet,
(Refertofigures26,27,30,31and32).
Forservicingpurposes,installashut-
offvalveupstreamfromthecoldwater
inlet.
The heater’s thermostat can be

11
regulated to provide domestic hot
water between 100°F (38°C) and
176°F(80°C).
CAUTION!!! Water
temperatureover125°F(52°C)can
cause severe burns instantly.
Since it is required that the heater
watertemperaturereachabove140°F
(60°C)inorderforthe heatingsystem
side of the unit to operate, it is
IMPERATIVE thata mixingvalve be
installed external of the heater to
furtherregulatethetemperatureofthe
domestichot water(See figures 26,
27, 28, 30, 31, 32, 33, 36 and 36).
CAUTION!!!Failuretoinstall
a domestic side mixing valve will
resultinsevere burns!
CAUTION!!! Piping and
components for domestic hot and
cold water, shall be suitable for use
with potable water, and shall not be
connected to any heating system or
components previously used with a
non-potablewaterheatingappliance.
CAUTION!!! The domestic
hot water circuit needs an ASME
approvedpressurereliefvalve,setat
150 psi (10 bar), installed as close
as possible to the heater.
Theremustbenovalvesbetweenthe
reliefvalve and theheater.Therelief
valve discharge pipe must not be
restrictedor plugged (see figure 26)
3.17 - Water
Hardness
In hard water areas (above 150
p.p.m), it is recommended that a
suitable water treatment device
(softener with filters) be installed.
Excessivebuildup ofminerals in the
heat exchanger can cause a non-
warrantyfailure. Waterhardnesscan
bedeterminedbyusing the standard
test or by checking with your local
waterauthority.
CAUTION!!! Toxic
chemicals, such as those used for
heater treatment, should not come
into contact with the potable water
usedfor spaceheating.
3.18 - Gas supply
Beforemakingany gas connections,
verifythattheheaterisbeingsupplied
with same gas type as indicated on
the rating plate. The rating plate is
located on the front panel of the
heater.
Thereare twopossible situations:
A– the gas and thesupply pressure
matchtheconfigurationoftheheater.
Inthis case,it ispossible to proceed
withconnecting theheater;
B - the gas and supply pressure do
not match the configuration of the
water heater. In this case it is
necessary to convert the heater for
the type of gas and pressure of the
availablesupply.
Theconversion kitis supplied
togetherwith thewater heater
- Install a manual gas cock outside
3 - INSTALLATION
of the heater. Refer to figure 4, for
the gas inlet location of the heater.
Gas piping to the heater must be
sufficienttoguaranteeasupplyofgas
to meet maximum requirements.
See Table in chapter 8 for max. and
min.valuesof gaspressure (Back of
manual).
- All piping must comply with local
codes and ordinances or with the
National Fuel Gas Code, (ANSI
Z223.1 NFPA No. 54), whichever
applies.
- The appliance and its individual
shutoff valve must be disconnected
from the gas supply piping system
during any pressure testing of that
system at test pressures in excess
of ½ psig, (3.5 kPa).
-Theappliancemustbeisolatedfrom
the gas supply piping system by
closing its individual manual shutoff
valve during any pressure testing of
thegas supply pipingsystem attest
pressuresequaltoorlessthan½psi,
(3.5 kPa).
- The appliance and its gas
connection must be leak tested
before placing the appliance in
operation.
- Before installation it is
recommendedtoperformathorough
internal cleaning of the gas supply
line. Figure 4 shows the positioning
ofthe gas connectionon the heater.
3.19 - Operating at
high altitudes
For installations in the United
States, the heater is rated for
operation at altitudes up to 2000 ft
(609 m). For installations at higher
altitudes in the United States,
follow local codes, or, in the
absence of local codes, ANSI
Z223.1/NFPANo. 54,TheNational
Fuel Gas Code. For installations in
Canada,the heateris ratedfor
installations up to 4500 ft. For
installationsabove thisaltitude,
followlocal/provincialcodes.

12
3.20 - Connecting
the supply,
return, gas, cold
water and hot
water
In its standard configuration, the
heater comes with the fittings
illustratedin figure26.
Moreinformation aboutthis matter
are in the next pages
3.21 - Safety relief
valve
AnASME approved safetyrelief
valve, set at 30 psi (2 bar), is
installedinside the heater.
Ifthesafety reliefvalvedischarges
periodically, this may be due to
thermal expansion in a closed
water supply system.
CAUTION!!! Do not plug
the safety relief valve.
There must be no valves
between the relief valve and
the heater. The relief valve
discharge pipe must not be
restricted or plugged.
Connectthesafety relief valve
outlet “E” (see fig. 5) to pipe “F”, (a
3/4”discharge pipe).
Ifthe safetyrelief valve “E” (see fig.
5) is not connected to the
discharge,openingof thevalvemay
result in damage to persons,
animalsor property.
3 - INSTALLATION
Figure 4 - Hydraulic and gas connections
Figure 5 - Safety relief valve discharge
connection
A = heating supply
B = heating return
C = gas
E = domestic cold water
D = domestic hot water
F = Position of the raccords

13
3.22 - Electrical
connections
3.22.1 - Overview
If installing an external
electrical source, the appliance
must be electrically grounded in
accordance with local codes or,
in the absence of local codes,
with the National Electrical
Code, ANSI/NFPA 70 and/or the
CSA C22.1, Electrical code
The heater must be connected to
a 115V 60Hz, single phase
electrical supply fused to 15 amps,
An electrical junction box (see
figures6, 7,8) isprovided for
connections for both the line
voltageof115V 60 Hz..
CAUTION!!! Label all
wires prior to disconnection
when servicing controls. Wiring
errors can cause improper and
dangerous operation.
Verify proper operation after
servicing.
CAUTION!!! The electrical
safety of the heater is assured only
when it has been correctly
connectedto an efficientgrounding
system constructed in compliance
with the safety regulations in effect.
This is an essential safety
requirementthat must beverified. In
caseof doubt, have the electrical
system thoroughly checked by a
qualifiedtechnician;
CAUTION!!! If theheater is
not correctly connected to a
grounding system, it will continually
go into the lock-out state.
Havea qualified technician check
that the electrical system is
adequatefor the electricalpower,
indicated on the rating plate,
requiredby the heater.
Theheater must be hooked up to
the electrical supply by means of a
fixed connection, (not with a
removableplug),the useof
adapters, multiple sockets or
extensions is not permitted.
Providethe installationof amain
emergencyswitch immediately
upstreamfromthe heater.
3 - INSTALLATION
Maintainthe correct polarity
betweenliveandneutral when
connectingthe heater.
Ensurethat the water and heating
system pipes are not used as
groundplates forthe electrical or
telephonesystem.
These pipes are not suitable for this
purpose, and in addition this could
rapidlylead toserious corrosion
damageto theheater,pipesand
radiators.
Theheater isnot provided with any
protectionagainst lightening
strikes.
3.22.2 - Choosing
the room
thermostat
Theheater isdesigned tofunction
with any type of room thermostat or
programmablethermostatprovided
with contacts for connecting the
heatercables,having thefollowing
characteristics:
- close = call for heating;
- open = don’t call for heating
- not electrically supplied;
- minimum electrical characteristics
24 Vac, 2.5A
3.22.3-Connecting
theroom
thermostat
Theroom thermostat must always
be located in a point of the house
wherethe temperatureis not
subject to sudden changes.
To connect the wires of the room
thermostat,proceed asfollows
(referto figures 6, 7 and 8):
luse a two-core wire with a
minimum cross section of 18
AWG;
lremovetheheaterfrontcover
panelfollowing theinstructions
givenin chapter 3.28;
lback off the three screws “B”
(see fig. 6) from box “A”;
lopenthe door “A” (see fig. 6);
lchoosea free cable clamp “C”
(see figure 8) that is not used by
otherconductors;
lunscrew“D” screws (see fig. 8)
of the cable clamp “C” and pass
the cable inside;
lconnect the two ends of the
cable to terminals 7 and 8;
lconnect the cable, using a
screwdriverto press down on the
terminalblock levers as shown in
figure8.

14
3 - INSTALLATION
3.22.4 - Connecting the
power supply cable
Toconnect the electrical powercable, proceed
as follows (refer to figures 6, 7, and 8):
lusea three-corecable with double isolation
and a minimum cross section of 18 AWG (1.5
mm2);
lopentheheater coverpanels following the
instructionsgiven inchapter 3.28;
lunscrew the three screws “B” from box “A”;
lopen the door “A” as shown in figure 7;
lunscrew screws “C” + “D” on cable clamp and
pass the cable inside;
l To connect the cables, use a screwdriver to
pushdown on the levers ofthe terminal block
as shown in figure 8.
CAUTION!!! if the “L1” live conductor
is inverted with the “N” neutral
conductor, the heater will go into
the lock-out condition.
CAUTION!!! if the ground system is
not efficient the heater will go into
the lock-out condition.
Figure 6 - Opening the electrical
connection box
Figure 7 - Opening the
junction box
Figure 8 - Connecting the power supply

15
3 - INSTALLATION
3.22.5-Functional
electricaldiagram
CE = Ignition module CS = Thermostat for C.S.B. (optional) CSJ = Cold start boiler jump CB = Control board DL1 = Gas valve lamp EA = Ignition electrods ER = Detection electrode F1 = Fuse F2 = Fuse GS = Sparks generator IG = Power switch IP = Heat and hot water selector IT = high or low power selector IVG = Gas valve service switch
P01 = circulator pump PR = Low water cut-off PSJ = Connection for plate heat exchanger or indirect water heater PWM = Blower speed control R1 = Relay on control board RC = Reset for ignition module RTC = Room thermostat connection SB = switches board (multiselector) SC = Low water cut-off and lock out lamp SG = Electrical power lamp SP1 = circulator pump light TP = Domestic hot water priority thermostat TR = Heater temperature control
TR1 = Transformer for gas valve TR2 = Transformer for blower TR3 = transformer for room thermostat circuit TS = High limit thermostat VE = Blower VG = Gas valve

16
3 - INSTALLATION
3.22.6 - Multiwire
electric diagram Legend: see chapter 3.22.5

17
3.23 - Venting systems
This heater can be fitted with either a
concentric or split type venting system.
Theapprovedtypes offlue gas discharge
configurationsfor thisheater are shown in figure
9
Particular attention must be taken when
installing the vent pipes that go through the wall
to the outside. It must always be possible to
carryout routinemaintenance operationsof the
flue. The vent pipe must be installed in such a
way that it can be removed, if needed, in the
future. Hence, a suitable sheath should be
prepared in which to insert the vent pipe. Both
ventingsystems are suitablefor ventingthrough
a wall 1” (25 mm) to 24” (609 mm) thick.
You must place the terminal in an open area,
andfollowthe followingguidelines:
lMake certain that exhaust gas does not re-
circulate back into the intake pipe.
lTopreventanyone fromwalking into the
exaust vent, maintain a 7 ft (2.13 m)
clearancefrom ground levelin walkways,
patio areas, alleys, or otherwise public
areas.
lMaintain a minimum 3 ft (0.9 m) clearance
fromanywindow ordoorway;
lNeverinstall aheat saveror similarproduct
to capture waste heat from exhaust;
lFollowlocal gas codes in your region or refer
toNational Fuel GasCode, or CanB149.1
INSTALLATIONCODES.
lMaintain at least 4ft (1.2 m) clearance to
electric, gas meters and exhaust fans.
lAlways place screens in openings (in intake
andexhaust) to preventforeign matterfrom
enteringtheheater.
lThe vent terminals, (concentric, split type
exhaust), must be a minimum of 12” (0.3
m)abovegroundlevel.
lIf split type vent will be venting into a
chimney, make certain that no other
appliancesare ventedinto it. Thispower-
ventedheater must not share a chimney.
Ventexhaust terminal should be inserted
into, but not beyond, inner wall of chimney.
lDo not vent into transient pipe. Warranty
will be void.
lDonot placevent terminalwhere flue
productscan cause corrosion.
lDue to the high efficiency of the heater,
condensationmay formin the discharge
piping as a result of the cooling of the flue
gases. It is therefore necessary to take every
precautionto prevent thiscondensation from
going inside the heater, by collecting it and
conveyingit outside the building. Followthe
instructionsfor conveying the condensation
providedinchapter 3.23.10.
Figure 9 - Approved types of flue gas discharge systems
3 - INSTALLATION

18
3.23.1 - Rotation
of the flue
discharge/air
intake fittings
Theconnection of the flue pipesto
theheater canbe rotatedthrough
360°,in increments of90°. This
makes it possible to choose
between4differentrelative
positions(see figure10) of the
dischargeand intakepipes,
allowingfor great versatilityof
installation.
Tocarry out thisoperation (refer to
figure10):
lremovethe fixingscrews “A”
fromthe topcover “B”.
lrotate the top cover to the
desiredposition.
lreinsert the fixing screws “A” and
lock them down without
excessiveforce.
Note: “C”indicates the front of the
heaterin thetop views.
In any position of rotation of the
cover, the intakeand discharge
fittings can be rotated on
themselves,allowingfor optimal
positioningof theconnections for
thecombustion analysis and/or for
thecondensation discharge.
3 - INSTALLATION
Figure 10 - Possibility of rotating the discharge and intake

19
3.23.2 - Kit for air
intake/flue
discharge
To assist the installer,
COSMOGAS has created flue kits,
complete with all the necessary
componentsfor flue dischargeand
airintake. Thefour kitsavailable
areas follows:
P/N 62617191. Split vent kit. This
kit is used if you are taking the
intakeair froma differentpoint than
the flue gas discharge point. If you
needadditional extentionsor
elbowsor otheraccessories, refer
to figures 14, 15 and 16.
P/N 62617186.Coaxial Vent &
Elbow Kit. This kit is used if you
aretaking in and discharging air
from/tothe outsideof the building
witha concentricvent. The pipe’s
discharge length is 3ft (1 m). If you
needextensions, elbowsor other
accessories,refer tofigure 22.
P/N 62617187. Coaxial Vent &
Straight Adapter Kit. This kit is
used to discharge air from/to the
outsideof thebuilding. Thepipe’s
discharge length is 3ft (1 m). If you
needextensions, elbowsor other
accessories,refer tofigure 23.
3 - INSTALLATION
P/N62617191
P/N62617186
P/N62617187

20
3.23.3 - 80/80 split
system
Theheaterisnotsupplied withfittings
for the flue gas discharge/air intake
connections. To connect the heater
to an 80/80 split system it is
necessarytoorderthespecialkitand
install it as shown in figure 11.
On the flue gas discharge side, it is
recommended to install stainless
steelpipes whichare moreresistant
tothe formationof condensation.
Takeparticular care with the
installation of the pipe sections that
pass through the wall to the
outside; these must always allow
fornormal maintenance actions,
thereforeinstall the pipesinside a
liner to enable them to be pulled
out.
Make sure that vent pipe is pitched
downfrom theunit towardthe
outsidewall 1/4” (6 mm)per foot
(0.3m). This will prevent any water
condensatefrom runningback into
theheater.
Also make sure that air intake pipe
is pitched down from the unit
towardthe outside wall 1/4” (6 mm)
perfoot (0.3 m). This will prevent
any water rain go into the heater.
The heater is equipped with a
condensation collector which, if
used, must be connected to a
dischargepipe(see fig.12details G,
H, L, M). Details G, H, L, M are not
suppliedwith theheater.
The condensation collector is
designed to discharge the liquid
producedby asingle heater.
If more than one heater is installed,
each one must be equipped with its
owncondensation discharge pipe.
The flue gas discharge/air intake
system can be extended up to the
maximum distance indicated in
chapter 8 at the end of the manual.
Every90°bendhasanequivalentloss
to 3ft (1 m) of straight piping. Every
45° bend has an equivalent loss to
1.5ft (0.5 m) of straight piping.
Iftheairintakeandfluegasdischarge
terminalsarepositionedonthesame
wall, they must be at a minimum
distanceof3ft(1m) fromeachother.
The center line of the vent opening
mustbeatleast 12”(305mm)above
gradeandatleast12”(305mm)from
Figure 13 - Fixing of the flue gas discharge and air intake pipes
3 - INSTALLATION
Figure 11 - Installation of the 80/80 split system
Figure 12 - Overall dimensions