Weil-McLain GV90+ Guide

Part number 550-142-803/0712
®
User’s
Information Manual
If the information in this manual is not followed exactly, a fire or explosion may result,
causing property damage, personal injury or loss of life.
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telephoneinyourbuilding.
• Immediately call your gas supplier from a neighbor’s telephone. Follow the gas supplier’s instructions.
• Ifyoucannotreachyourgassupplier,calltheredepartment.
Installation & service must be performed by a qualified installer, service technician or the gas supplier.
Series 2
Gas-Fired Water Boilers

Part number 550-142-803/0712
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GV90+ Series 2 gas-fired water boiler — User’s Information Manual
Please read this page first
How to use this
manual . . . To . . . Read/use . . . Page . . .
Learn
precautions Warnings and definitions 3
Prevent air
contamination
Laundry room or pool — make sure boiler air is
piped to boiler per manual.
Read list of air contaminants you must avoid. Have
boiler air piped in if you can’t avoid.
4
Maintain
boiler
Set up a plan for maintaining the boiler using
the schedule included in this manual.
Schedule an annual start-up by a qualified
service technician before every heating season.
5
Locate boiler
components How the boiler works and illustration. 10
Start — or —
Shutdown
boiler
Follow the Lighting instruction sheet details to
start or shutdown your boiler. 12
Troubleshoot
common
problems
Use the common problems/solutions table to
resolve typical heating system/boiler problems. 13

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STOP!! — Read before proceeding
Failure to adhere to the guidelines on this page can result
in severe personal injury, death or substantial property
damage.
Boiler service and maintenance —
• Toavoidelectricshock,disconnect electrical supply before
performing maintenance.
• To avoidsevereburns,allow boiler to cool before performing
maintenance.
• Youmustmaintain the boiler as outlined in the manual and have
the boiler started up and serviced at least annually by a
qualified service technician to ensure boiler/system reliability.
Boiler operation —
• Donotblockowofcombustionorventilationairtoboiler.This
boilerisequippedwithacontrolwhichwillautomaticallyshutdown
theboilershouldairorventbeblocked.Ifventorairblockageis
easilyaccessibleandremovable,removeit.Theboilershouldattempt
torestartwithinanhour.Ifblockageisnotobviousorcannotbe
removed,havetheboilerandsystemcheckedbyaqualiedservice
technician.
• Should overheating occur or gas supply fail to shut off,DONOT
turnoffordisconnectelectricalsupplytocirculator.Instead,shutoff
the gas supply at a location external to the appliance.
• Do not use this boiler if any part has been under water.Imme-
diatelycallaqualiedservicetechniciantoinspecttheboilerandto
replace any part of the control system and any gas control that has
beenunderwater.
Combustion air —
• DO NOT install combustion air intake where there is a risk of
combustion air contamination.
Carbon monoxide detector —
• For Direct Exhaust units, a carbon monoxide detector is required
intheboilerroom.Thecarbonmonoxidedetectormustbewired
on the same electrical circuit as the boiler.
• For Direct Ventunits,acarbonmonoxidedetectorthatiswiredon
the same electrical circuit as the boiler is strongly recommended.
Boiler water —
• Do not use petroleum-based cleaning or sealing compounds in boiler
system.Gasketsandsealsinthesystemmaybedamaged.Thiscan
result in substantial property damage.
• Leaks in boiler or piping must be repaired at once to prevent
make-up water. Use this boiler ONLY in a closed-loop system.
Continualfreshmake-upwaterwillreduceboilerlife.Mineralbuild-
up in heat exchangers reduces heat transfer, overheats the materials,
andcausesfailure.Additionofoxygencarriedinbymake-upwater
can cause internal corrosion.
• Do not add cold water to hot boiler.Thermalshockcancauseheat
exchangertocrack.
Freeze protection fluids —
• NEVER use automotive or standard glycol antifreeze. Use only freeze-
protectionuidsmadeforhydronicsystems.Followallguidelines
givenbytheantifreezemanufacturer.Thoroughlycleanandush
any replacement boiler system that has used glycol before installing
thenewboiler.
User — Have this boiler serviced/
inspectedbyaqualiedservicetech-
nician, at least annually.
Failuretocomplywiththeabove
could result in severe personal injury,
death or substantial property dam-
age.
 Whencalling orwritingaboutthe
boiler— Please have the boiler
model number from the boiler rat-
ing label and the CP number from
theboilerjacket.
Hazard definitions
Thefollowingdenedtermsareusedthroughout
this manual to bring attention to the presence
ofhazardsofvariousrisklevelsortoimportant
information concerning the life of the product.
 Indicatespresenceofhazardsthat
willcauseseverepersonalinjury,
death or substantial property dam-
age.
 Indicatespresenceofhazardsthat
can cause severe personal injury,
death or substantial property dam-
age.
 Indicatespresenceofhazardsthat
willorcancauseminorpersonal
injury or property damage.
 Indicatesspecialinstructionsonin-
stallation, operation or maintenance
that are important but not related to
personal injury or property damage.

Part number 550-142-803/0712
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GV90+ Series 2 gas-fired water boiler — User’s Information Manual
Air contamination
Common household and hobby products often contain
uorineorchlorinecompounds.Whenthesechemicals
pass through the boiler, they can form strong acids in
thevent system or boiler. Theacidcaneatthrough
theventorboilerwall,causingseriousdamageand
presenting a possiblethreatof uegasspillageinto
the building.
Pleasereadtheinformationbelow.Ifthecontaminating
chemicalswillbepresent,haveyourinstallerpipethe
boiler air from outside per the Boiler manual.
Iftheboilerisinstalledinany area
likely to cause contamination, or if
productswhichwouldcontaminatethe
air cannot be removed, you must pipe
combustion air to the boiler air in-
take.Contaminatedcombustionairwill
damage the boiler and vent system, re-
sulting in possible severe personal injury,
death or substantial property damage.
Do not operate a GV90+ boiler in
a laundry room or pool facility, for
example,without usingducted outside
air.Theseareaswillalwayscontaincon-
taminants.
Prevent combustion air contamination —
Combustion air contamination:
Ensure that the combustion air will not contain any of
the contaminants in Figure 1.
 Combustionairsupplyopeningsorintaketerminations
mustNOTbenearaswimmingpool,forexample.
Avoid areas subject to exhaust fumes from laundry facilities.
Theseareaswillalwayscontaincontaminants.
Figure 1 Corrosive contaminants and sources
Products to avoid
Spray cans containing chloro/fluorocarbons
Permanent wave solutions
Chlorinated waxes/cleaners
Chlorine-based swimming pool chemicals
Calcium chloride used for thawing
Sodium chloride used for water softening
Refrigerant leaks
Paint or varnish removers
Hydrochloric acid/muriatic acid
Cements and glues
Antistatic fabric softeners used in clothes dryers
Chlorine-type bleaches, detergents, and cleaning solvents found in
household laundry rooms
Adhesives used to fasten building products and other similar products
Excessive dust and dirt
Areas likely to have contaminants
Dry cleaning/laundry areas and establishments
Swimming pools
Metal fabrication plants
Beauty shops
Refrigeration repair shops
Photo processing plants
Auto body shops
Plastic manufacturing plants
Furniture refinishing areas and establishments
New building construction

Part number 550-142-803/0712 5
GV90+ Series 2 gas-fired water boiler — User’s Information Manual
Perform maintenance per schedule below
Figure 2 Service and maintenance schedules
Service technician
(see Boiler Manual for instructions) Owner maintenance (see following pages for instructions)
Annual start-up
Follow the procedures listed in
the Boiler Manual.
Daily
• Checkboilerarea
• Checkairopenings
• Checkpressuregauge
Monthly
• Checkboilerinteriorpiping
• Checkventingsystem
• Checkairvents
• Checkcondensatedrainsystem
• Checkreliefvalve
Periodically
• Testlowwatercutoff(ifused)
• Cleanventtermination/airintake
screens
Every 6 months • Oilblowermotor
• Operatereliefvalve
End of season • Shutdownprocedure

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GV90+ Series 2 gas-fired water boiler — User’s Information Manual
DAILY
Maintenance
Boiler must
be serviced
and
maintained
Check boiler area
 Topreventpotential of severepersonalinjury,deathorsubstantialproperty
damage,eliminateallmaterialsdiscussedbelowfromtheboilervicinity.Ifcon-
taminants are found:
Removeproductsimmediatelyfromthearea.Iftheyhavebeenthereforanex-
tendedperiod,callaqualiedservicetechniciantoinspecttheboilerandvent
system for possible damage from acid corrosion.
Ifproductscannotberemoved,immediatelycallaqualiedservicetechnicianto
install an outside combustion air source for the boiler (if not already installed).
1. Combustible/ammablematerials—Donotstorecombustiblematerials,gasolineorany
otherammablevaporsorliquidsneartheboiler.Removeimmediatelyiffound.
2. Aircontaminants—Productscontainingchlorineoruorine,ifallowedtocontaminate
theboilerintakeair,willcauseacidiccondensateintheventandboiler.Thiswillcause
signicantdamagetotheventand/orboilerifallowedtocontinue.Readthelistofpotential
materialslistedonpage4ofthismanual.Ifanyoftheseproductsareintheroomfrom
whichtheboilertakesitscombustionair,theymustberemovedimmediatelyortheboiler
combustionairmustbesuppliedfromoutside.SeeWARNINGabove.
Check air openings
1. Verify that combustion and ventilation air openings to the boiler room and/or building
are open and unobstructed.
2. Verifythatboilerventdischargeandairintakearecleanandfreeofobstructions.Remove
anydebrisontheairintakeorueexhaustopenings.
Check boiler pressure/temperature gauge
1. Makesurethepressurereadingontheboilerpressure/temperaturegaugedoesnotexceed
24psig.Higherpressuremayindicateaproblemwiththeexpansiontank.
2. Contactaqualiedservicetechnicianifproblempersists.
User maintenance procedures
 Theboilershouldbeinspectedandstartedannually,atthebeginningoftheheat-
ingseason,onlybyaqualiedservicetechnician.Inaddition,themaintenance
andcareoftheboilerdesignatedonpage5andexplainedonthefollowingpages
mustbeperformedtoassuremaximumboilerefciencyandreliability.Failure
to service and maintain the boiler and system could result in equipment failure,
causing possible severe personal injury, death or substantial property damage.
 Thefollowing information provides detailed instructions forcompletingthe
maintenanceitemslistedinthemaintenanceschedule,page5.Inadditionto
this maintenance, the boiler must be serviced and started up at the beginning of
eachheatingseasonbyaqualiedservicetechnician.

Part number 550-142-803/0712 7
GV90+ Series 2 gas-fired water boiler — User’s Information Manual
MONTHLY
Maintenance
Check boiler interior piping
1. Removeboilerjackettop.
2. Visuallyinspectforleaksaroundinternalpiping,circulators,reliefvalveandotherttings.
Immediatelycallaqualiedservicetechniciantorepairanyleaks.
 Haveleaksxedatoncebyaqualifedservicetechnician.Continualfreshmakeup
waterwillreduceboilerlife.Mineralscanbuildupinsections,reducingheat
transfer, overheating cast iron, and causing section failure.
Do not use petroleum-based cleaning or sealing compounds in boiler
system. Severe damage to boiler and system components can occur, resulting in
possible severe personal injury, death or substantial property damage.
User maintenance procedures (continued)
Check venting system
1. Visuallyinspecttheuegasventpipingforanysignsofblockage,leakageordeterioration
ofthepiping.Notifyyourqualiedservicetechnicianatonceifyoundanyproblem.
Failure to inspect the vent system as noted above and have them repaired by a
qualifed service technician can result in vent system failure, causing severe per-
sonal injury or death.
Check automatic air vents (if used — use automatic air
vents with diaghragm-type expansion tanks only)
1. See Figure 3.
2. Removethecapfromanyautomaticairventinthesystemandcheckoperationbydepress-
ingvalve“B”slightlywiththetipofascrewdriver.
3. Iftheairventvalveappearstobeworkingfreelyandnotleaking,replacecap“A”, twisting
allthewayon.
4. Loosencap“A”oneturntoallowventtooperate.
5. Have vent replaced if it does not operate correctly.
Figure 3 Automatic air vent
85036
A
B

Part number 550-142-803/0712
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GV90+ Series 2 gas-fired water boiler — User’s Information Manual
Check condensate system
1. NOTICE — Toimproveclarity,this
illustration of the condensate trap is
shownwithnoairinletpipeattached.
Ifyourboilerhasanairpipeconnected
here,DONOTtamperwithit.Thetrap
isalsoshownasitemmon page 11.
2. Inspectthe condensateP-trap (item 1
intheillustrationatright).Thetrapis
translucent.Yo u shouldbeableto see
waterinthetrapasshown.
3. Ifthetrapdoesnotcontainwater,turn
offthe boilerON/OFFswitchandcall
your boiler service technician imme-
diately.
4. Item2intheillustrationisthetubingor
pipefromtheboilercondensateoutlettothecondensatedrainorcondensatepump.Inspect
thistubingorpiping,makingsureitisingoodconditionandnotobstructed.
 Ifthecondensatetrapisdryorthecondensatelineisdamagedorobstructed,
thereisariskofuegasowintothebuilding.Theboilermustnotbeoperated
andmustbeinspectedandservicedonlybyaqualiedservicetechnician.Failure
tocomplywiththisdirectivecouldresultinthepossibilityofseverepersonal
injury, death or substantial property damage.
Check boiler relief valve
1. Inspecttheboilerreliefvalveandthereliefvalvedischargepipeforsignsofweepingor
leakage.
2. Ifthereliefvalveoftenweeps,theexpansiontankmaynotbeworkingproperly.Immediately
contactyourqualiedservicetechniciantoinspecttheboilerandsystem.
Test low water cutoff (if installed)
1. Ifthesystemisequippedwithalowwatercutoff,testthelowwatercutoffperiodically
duringtheheatingseason,followingthelowwatercutoffmanufacturer’sinstructions.
Clean vent termination & air intake screens
1. Removealllintanddebrisfromboththeboilerairintakescreenandtheuedischarge
screen.
2. Theboilercontrolmodulewillsenseblockageoftheairintakeorueandlockoutifthe
blockageisexcessive.Itwillsignalthefailurebyashingtheappropriateindicatorlights
on the control board.
3. Ifremovingthedebrisdoesnotallowtheboilertooperatecorrectlyafterwards,contact
your qualifed service technician to inspect the boiler and vent/air systems.
User maintenance procedures (continued)
MONTHLY
Maintenance
PERIODIC
Maintenance

Part number 550-142-803/0712 9
GV90+ Series 2 gas-fired water boiler — User’s Information Manual
Operate boiler relief valve
1. Before proceeding, verify that the relief valve outlet has been piped to a safe place of dis-
charge,avoidinganypossibilityofscaldingfromhotwater.
Toavoidwaterdamageorscaldingduetovalveoperation,ametaldischargeline
mustbeconnectedtoreliefvalveoutletandruntoasafeplaceofdisposal.This
discharge line must be installed by a qualifed heating installer or service techni-
cianinaccordancewiththeinstructionsintheGV90+ Boiler Manual.The
discharge line must be terminated so as to eliminate possibility of severe burns
should the valve discharge.
2. Readtheboilerpressure/temperaturegaugetomakesurethesystemispressurized.
3. Liftthereliefvalvetopleverslightly,allowingwatertorelievethroughthevalveanddis-
charge piping.
4. Ifwaterowsfreely,releasetheleverandallowthevalvetoseat.Watchtheendoftherelief
valvedischargepipetoensurethatthevalvedoesnotweepafterthelinehashadtimeto
drain.Ifthevalveweeps,lifttheseatagaintoattempttocleanthevalveseat.Ifthevalve
continuestoweepafterwards,contactyourqualiedservicetechniciantoinspectthevalve
and system.
5. Ifwaterdoesnotowfromthevalvewhenyouliftthelevercompletely,thevalveordischarge
linemaybeblocked.Immediatelyshutdowntheboiler,followingthelightinginstructions
ontheinsidejackettop.Callyourqualiedservicetechniciantoinspecttheboilerand
system.
Follow boiler shutdown procedure
1. Follow“TO TURN OFF GAS TO APPLIANCE” on the Operating instruction on the
insideofthejackettoppanel.Yo u willalsondtheseinstructionsonpage 12 of this manual.
2. Donotdrainsystemunlessexposuretofreezingtemperatureswilloccur.
3. Donotdrainthesystemifitislledwithanantifreezesolution.
4. Donotshutdownboilersusedfordomesticwaterheating.Theymustoperateyear-round.
Oil blower motor
1. Removethejackettoppaneltoaccesstheblower
motor.
2. UseonlyAnderol465.DONOTusehousehold
universal oils.
Use only Anderol 465 to lubricate the
blowermotor.Donotusecommonuni-
versal household oils.
3. See Figure 4
4. Placeafewdropsofoilineachofthetwooilercups
onthesideoftheblowermotor.
Figure 4 Blower motor
User maintenance procedures (continued)
EVERY
6 MONTHS
Maintenance
END OF
SEASON
Maintenance

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1 Integrated boiler control
Theintegratedboilercontrol(IBC)respondstosignalsfromtheroomthermostat,air
pressure switch,inlet watersensor,boiler watertemperature sensorandboiler limit
circuittooperatethecirculators,gasvalve,igniterandblower.Whenaroomthermostat
callsforheat,theIBCstartsthesystemcirculatorandblower.
TheIBCrunstheblowertopurgetheboileruepassages,thenturnsontheigniterand
letsitwarmup.
Afterigniterwarm-up,theIBCopensthegasvalve,turnstheigniteroff,andchecksfor
ame.Theamemustcomeonwithin4secondsortheIBCwillshutdownandtrythe
full cycle again.
Whentheroomthermostatissatised,theIBCturnsofftheboilercomponentsand
waitsforthenextheatcall.
TheIBCindicatorlightsshownormalsequencewhenthelightsareonsteady.Whena
problemoccurs,theIBCashescombinationsoflightswhichindicatethemostlikely
reason for the problem.
While attempting to satisfy the heat demand, the control module monitors the boiler
temperaturechangesviathetemperaturesensorsanddetermineswhetherornotthe
availablehotwaterwillsatisfythedemand,onlyrunningthecirculator.Ifadditional
heat is needed, the sequence continues. When DHW (if used) calls for heat, sequence
above is bypassed.
2 Transformer
Thecontroltransformerreduceslinevoltageto24voltsforthegasvalveandlimitcircuit.
3 Blower
Theblowerpullsinairandmixesitwithgasfromthegasvalve.Theblowerforcesthis
mixture into the burner for combustion inside the boiler chamber.
4 Recuperator
Therecuperatorisastainlesssteelheatexchangerthatincreasesboilerefciencybyex-
tractingadditionalheatfromtheuegases.Returnwaterpassesthroughtherecuperator
before entering the boiler.
5 Water temperature sensor
Thewatertemperaturesensorprovidesasignaltothecontrolmoduletoturnoffthegas
valveifthetemperatureintheboilergoesaboveitssetting.(Thecirculatorwillcontinue
to run as long as there is a call for heat.)
6 System circulator
Thesystemcirculatorcirculateswaterthroughtheexternal(system)piping.Theow
rateofthecirculatoriscontrolledbytheIBC,dependingonthetemperatureofthewater
entering the boiler sections. Pump must remain on boiler — do not remove.
7 Bypass circulator
TheIBCoperatesthebypasscirculatortomixhotwaterfromtheboileroutletwith
colderreturnwaterfromthesystemasneededtopreventcondensationofuegasesin
the cast iron heat exchanger.
When thewaterreturningtotheboiler isbelow 140°F,theIBC regulatesthebypass
circulatorandsystemcirculatorowratestoraisethereturnwatertemperatureupto
140°Fbeforeitentersthecastironsections.Bybalancingtheseowrates,theIBCcan
protectagainstcondensationevenifreturnwaterisaslowas60°F.
Pump must remain on boiler — do not remove.
8 Air pressure switch
TheairpressureswitchsignalstheIBC,tellingthecontrolwhetherairismovingthrough
theblower.
9 Return water temperature sensor
Thewatertemperaturesensormonitorsthetemperatureofthewaterenteringtheboiler
sections.ThesensorsendsthisinformationtotheIBC.TheIBCdetermineshowmuch
toadjustthecirculatorowratestoprovideatleast140°Fwatertothecastironheat
exchanger.
How it works . . .
LEGEND
a Supplytosystem,1”NPT
b Returnfromsystem,1”NPT
c Combustionairinlettting —
3” PVC connection
d Flue outlet — 3”PVC connection
e Gas valve — negative pressure
regulated gas control
f Pressure/temperature gauge
g Fluewayinspectionportcover
h Sensor hose trap
i Manualairvent
j Relief valve
k Thermalfuse—aone-timefuse
devicethatshutsboileroffifue
temperature exceeds its setpoint
m Condensate trap line — shipped
loosewithboiler,eldinstalled
n Condensate drain connection —
½” PVC female
Thisboileruses a negative-pressure-
regulated gas valve, set for an outlet
pressureapproximately–0.20”water
column.
DO NOT set the outlet pressure higher
than factory setting.

Part number 550-142-803/0712 11
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GV90+ Series 2 Water Boiler

Part number 550-142-803/0712
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GV90+ Series 2 gas-fired water boiler — User’s Information Manual
Operating instructions
Before attempting to start the boiler, check the boiler pressure temperature gauge.Ifboilerandsystemarefull
ofwaterandproperlypressurized,thegaugeshouldreadatleast12psigonmostsystems.Operatingtheboilerwithout
properwatercontentwilldamageboilerandcontrolsandcouldresultinseverepersonalinjury,deathorsubstantial
property damage.
Figure 5 Operating instructions

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Common problems and solutions
Symptom Common Causes Possible Corrections
Rapid cycling — boiler
turns on and off frequently
Thermostat installed where drafts
or heat affect reading Locate thermostat on inner wall away from heat sources or cool drafts.
Heat anticipator in thermostat
adjusted incorrectly Adjust thermostat per manufacturer’s instructions.
Incorrect boiler temperature
setting Set boiler temperature according to system needs.Maximum setting is 200°F. Increase
boiler temperature setting to decrease
cycling.
Insufficient water flow through
boiler Check all valves to and from boiler. Return to proper setting.
Confirm circulator size.
Frequent release of water
through relief valve
Expansion tank sized too small Call qualified service technician to check
expansion tank operation and size.
Flooded expansion tank Call qualified service technician to check
expansion tank operation.
Inoperative limit control Call qualified service technician to replace
limit control.
Need to frequently add
makeup water
Leaks in boiler or piping Have qualified service technician repair
leaks at once to avoid constant use of
makeup water. Makeup water can cause
mineral deposits which, in turn, can cause
boiler section failure.Do not use petroleum-
base stop-leak compounds.
Black water condition Oxygen corrosion due to leaks in
boiler and piping Have qualified service technician repair at once.Keep pH of water between 7.0 to 8.5.
Large temperature swings
in living space
Incorrect Economy setting Adjust Economy setting on boiler control.

Part number 550-142-803/0712
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Common problems and solutions (continued)
Symptom Common Causes Possible Corrections
Popping or percolating
noise heard in boiler
Mineral deposits in sections due
to constant use of makeup water Call qualified service technician to de- lime boiler, if necessary. In some cases,
deposits will be too heavy to remove with
de-liming procedures.
Have qualified service technician repair
leaks to eliminate need for constant
makeup water.
Incorrect pH of boiler water Call qualified service technician to check
pH level and correct.pH should be
maintained between 7.0 to 8.5.
Insufficient water flow through
boiler Check all valves to and from boiler. Return to proper setting.
Confirm circulator size.
Metal flakes found in vent
outlet or vent starter tee —
flueway corrosion
Contaminated combustion air
supply — See page 4 in this
manual.
Remove any contaminating products.See
page 4 in this manual.
Provide outside air for combustion. Have
qualified service technician pipe-up kit.
Condensation of combustion
gases in boiler sections Have qualified service technician check operation of mixing system.Repair/replace
if necessary.
Some radiators or
baseboard units do not
heat or are noisy
Air in system Bleed air from system through air vents in
radiators or baseboard units.
Low system pressure Fill to correct pressure.
Check for leaks in boiler or piping. Have
qualified service technician repair at once.
Boiler temperature set too low Adjust boiler temperature to higher setting.

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GV90+ Series 2 gas-fired water boiler — User’s Information Manual
NOTES

GV90+ Series 2 gas-fired water boiler — User’s Information Manual