Nordyne GR4G*090 Series Guide

Read this owner information thoroughly before attempting to operate or maintain this unit to
becomefamiliarwiththecapabilitiesanduseofyourappliance.Keepthisliteraturewhereyouhave
easyaccesstoitinthefuture.Ifaproblemoccurs,checktheinstructionsandfollowrecommendations
given.If these suggestionsdon’t eliminate yourproblem, call yourNORDYNE Servicing Contractor
(Service PRO).
Anyadditions,changes,orconversionsrequiredinorderfortheappliancetosatisfactorilymeetthe
application needs must be made by a qualified installer, service agency, or the gas supplier using
factory specified and approved parts.
IMPORTANT
Single Package Gas Heating/Electric Cooling Rooftop Unit
GR4G(*) Series - 090/120/150/180
Single Package Gas Heating /Electric Cooling Rooftop Unit
USER’S INFORMATION MANUAL
— Donotstoreorusegasolineorotherflammable
vaporsandliquidsinthevicinityofthisorany
other appliance.
— Installationandservicemustbeperformedby
a qualified installer, service agency, or the
gas supplier.
WARNING: If the information in this manual is
not followed exactly, a fire or explosion may
resultcausingpropertydamage,personalinjury,
or loss of life.
FOR YOUR SAFETY
— WHATTODOIFYOUSMELLGAS:
• Do not try to light any appliance.
• Do not touch any electrical switch; do
not use any phone in your building.
• Immediatelycallyourgassupplierfrom
a neighbor's phone. Follow the gas
supplier's instructions.
• If you cannot reach your gas supplier,
call the fire department.
7.5/10 Ton
GR4G* 090 Series Shown 12.5/15 Ton
GR4G* 150/180 Series

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GENERAL INFORMATION
This gas heating/electric cooling unit has been de-
signed and built to provide many years of safe and
dependable comfort, providing it is properly installed
andmaintained.Withregularmaintenance,thisunitwill
operatesatisfactorilyyearafteryear.Abuse,improper
use,and/orimpropermaintenancecanshortenthelife
of the appliance and create hazards for you. Please
read this manual carefully to familiarize yourself with
operation,maintenance,andsafetyproceduresforthis
unit.
A regular service and maintenance schedule should be
establishedtoensureefficientandsafeoperationoftheunit.
Contact your dealer for a periodic unit inspection by a
qualified service technician.
!
WARNING:
To avoid possible equipment damage, fire, or
death, the following instructions must be
observed regarding unit location, combustion
air requirements, and operation procedures.
GasHeating/ElectricCoolingUnitLocation—Thearea
aroundthegasheating/electriccoolingunitandthevicin-
ityofanyothergasappliancesmustbekeptclearandfree
ofcombustiblematerials, gasoline, andother flammable
vapors and liquids. Do not store or use flammable items
such as paint, varnish, or strippers in the vicinity of the
unit.
Donotusetheareaaroundtheunitasastoragearea.This
areamustbekeptclearandclean.Theunitmustalsobe
keptclearoflooseorexposedinsulationmaterials.Examine
the unit's area when it is installed or when insulation is
added, since some insulation materials may be
combustible.
Donotusethisapplianceifanyparthasbeenunderwater.
Immediatelycall a qualifiedservice technician toinspect
theunitandtoreplaceany partofthecontrol systemand
anygas control whichhas been underwater.
Familiarizeyourselfwiththecontrolsthatshutoffthegas
and electrical power to the unit. If the unit is to be shut
downforanextendedperiodoftime,turnoffboththegas
andelectricalpower.Foryoursafetyalwaysturnoffboth
thegasandelectricalpowerbeforeperformingserviceor
maintenanceonthefurnace.
CombustionAirSupply—Thegasheating/electriccooling
unit needs an adequate supply of combustion and
ventilationairforproperandsafeoperation.Donotblock
or obstruct air openings on the unit or air openings
supplying the area where it is installed.
If the unit is operated with inadequate combustion air
supply,theflameroll-outcontrolswitchlocatedabovethe
burnerswillopen,turningoffthegassupplytotheburners.
The flame roll-out control is a manual-reset device. DO
NOT install a jumper wire across this switch to defeat its
function.DONOTresetthecontrolwithoutidentifyingand
correctingthefaultconditionwhichcausedthecontrol to
trip. If this switch must be replaced, use only the factory
specifiedreplacementpart.
!
CAUTION:
Combustion air must not be drawn from a
corrosive atmosphere.
Tomaximizeheatexchangerlife,thecombustionairmust
be free of chemicals which form corrosive acidic com-
pounds in the combustion gases. Some examples of
thesechemicalsarechlorine,fluorine,andsulphur.Some
common sources of these chemicals are detergents,
bleaches, aerosol sprays, cleaning solvents, and a wide
varietyof commercial andhousehold products.
Ductwork—
!WARNING:
Failureto preventproductsof combustionfrom
being circulated into the occupied space can
create potentially hazardous conditions includ-
ing carbon monoxide poisoning that could re-
sult in personal injury or death.
The duct connections must be physically sound and
sealedtotheunit'scasingtopreventproductsofcombustion
fromentering the occupiedspace.
The return air and circulating air ductwork must not be
connected to any other heat producing device such as a
fireplace insert, stove, etc. Doing so may result in fire,

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Figure 1. Typical Thermostat
explosion,personalinjury,carbonmonoxidepoisoning,or
propertydamage.
OPERATING INSTRUCTIONS
CoolingOperation—2Stage
1. Set the thermostat system switch to COOL and the
thermostat fan switch to AUTO. (See Figure 1)
2. Set the thermostat temperature selector to the de-
siredtemperaturelevel.Theoutdoorfans,compres-
sors, and indoor blower will all cycle on and off to
maintaintheindoortemperatureatthedesiredcooling
level.
HeatingOperation —2Stage
1. Set the thermostat system switch to HEAT and the
thermostat fan switch to AUTO. (See Figure 1)
2. Set the thermostat temperature selector to the de-
sired temperature level. The indoor blower and gas
heat module will cycle on and off to maintain the
indoortemperatureatthedesiredheatinglevel.
NOTE: There is a factory set 3 minute time delay
between Stage 1 and Stage 2 heat when Stage 2
heatingisrequired.
!WARNING:
Shouldoverheatingoccur,orthegassupplyfail
to shut off, shut off the manual gas valve to the
unit before shutting off the electrical supply.
NOTE: This unit is equipped with a manual-reset flame
roll-out limit switch. This switch acts to verify that the
burnerflameisbeingdrawnintotheheatexchangertubes.
Iftheflameisnotbeingdrawnintothetubes,theflameroll-
out switch will open within several seconds. When this
switch opens, the gas valve will de-energize to stop the
flow of gas. The combustion inducer will stay energized
andcontinuetooperateuntilthethermostatissatisfiedor
theswitchisclosed.Donotresettheflameroll-outswitch
before identifying and correcting the fault condition that
caused the switch to open. If the switch will not reset or
continues to open, immediately contact a qualified
servicemanto identifyandrepair theproblem.
System Shutdown—Set the thermostat system
switch to OFF and the thermostat fan switch to AUTO.
(SeeFigure1)
Thesystemwillnotoperate,regardlessofthethermostat
temperatureselector(s)setting.

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ToOperatetheIndoorBlowerContinuously—Setthe
thermostatfanswitchtoON(maybecalledCONTonsome
thermostatmodels).(SeeFigure1)
The indoor blower will start immediately, and will run
continually until the fan switch is reset to AUTO.
Thecontinuous indoor blower operation canbeobtained
with the thermostat system switch set in any position,
includingOFF.
Thecontinuousindoorbloweroperationistypicallyusedto
circulatetheindoorairtoequalizeatemperatureunbalance
due to a solar load, cooking, or fireplace operation.
SYSTEM MAINTENANCE
!
CAUTION:
Be certain the electrical power to the unit is
disconnectedandthegas is shutoffbeforedoing
the following recommended maintenance.
Proper maintenance is most important to achieve the best
performancefromtheapplianceandshouldbeperformedby
aqualifiedservicetechnicianatleastonceayear.Followthe
maintenancescheduleandtheinstructionsbelowforyears
ofsafe, troublefreeoperation.
• Donotplacecombustiblematerialsonoragainst
thecabinet.
• Do not store gasoline or any other flammable
vapors and liquids in the vicinity of the unit.
• Annuallyinspect the physicalsupport of theunit
to ensure that it is physically sound without sag-
ging,cracks, gaps, etc.,aroundthe base soasto
provideasealbetweenthesupportandthebase.
• Annually inspect the return-air connection to
ensure that it is physically sound and is still
sealed to the casing of the unit.
• Annually inspect the unit, ductwork, and vent
systemforsigns ofphysical deterioration.
•Alwaysreplacethedoorsontheunitafterservicing.
Do not operate the unit without all doors and
covers in place.
!CAUTION:
Do not strike any of the internal electrical
components while cleaning.
1.RegularCleaning:
• Remove any debris from the outdoor coil, being
careful not to damage the aluminum fins.
• Checkforandremoveanyobstructionstocondenser
airflow.
• Cleantheblowercompartmentregularlyduringthe
heating and cooling seasons to remove any dust
that may have accumulatedinthe compartment or
on the blower and motor. Buildup of dust on the
blowerandmotorcancreateexcessiveloadsonthe
motor resulting in higher than normal operating
temperaturesandpossibleshortenedservicelife.
2. Air Filters:
!
WARNING:
Neveroperatethe unitwithoutafilter inthe return
airsystem.Dust andlintin thereturnaircan build
uponthe internal components,resultingina loss
of efficiency, equipment damage, and possible
fire risk.
GR4G(M,N) units are factory equipped with pleated 2”
disposable filters. The filters should be checked periodi-
callyandreplaced(orcleaned)whennecessarywithfilters
ofthe samedimensional size. Replaceusing disposable
filters with a minimum airflow rating of 500 FPM or
permanentfiltersonly.For7.5and10tonmodelsonly:the
filterrackisfieldadjustabletoaccommodate1”permanent
filters. DO NOT use 1” disposable filters in GR4G(M,N)-
090/120units.
NOTE:FiltersmustbeULCapprovedorequivalentforuse
inCanada.
Alwaysreplacethefilteraccesspanelsafterchanging
orcleaningthefilters.Donotoperateunitwithoutthe
filter access panels in place.
3.MotorLubrication:
!WARNING:
Lubrication of the motors in this unit is not
required. Do not lubricate any motor in this
product.

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Figure 3. Burner Inspection
Themotorsforthecirculatingairblower,outdoorfan,and
combustion blower are pre-lubricated at the factory. No
further oiling is required for the life of this product.
!
CAUTION:
Somecomponentsintheburnervestibuleareat
high temperatures while the burners are
operating.Usecautionto avoidpersonal injury.
4.BurnerMaintenance:
Check the burner flames at the start of every heating
season.Setthethermostattoatemperaturesettingabove
the room temperature. With the louvered service panel in
place,rotatetheburnerobservationporttotheopenposition
andvisuallyinspecttheburnerassemblytomakesurethat
the flame is drawn directly into the center of the heat
exchangertube(SeeFigure3).Inaproperlyadjustedburner
assembly the flame color should be blue, however, some
light yellow streaks may occur on the outer portions of the
flame.
BeforeCallingATechnician:
If the unit fails to operate in cooling, be certain of the
following:
1. The thermostat is operating properly. Refer to
“CoolingOperation.”
2. The electrical power to the unit is turned on.
3. The filters are not dirty.
If the unit fails to operate in heating, be certain of the
following:
1. The thermostat is operating properly. Refer to
“HeatingOperation.”
2. The electrical power to the unit is turned on.
3. The gas is turned on.
4. The filters are not dirty.

¢708343&¤
7083430
7083430(Replaces7081210)
Specifications and illustrations subject to change
withoutnoticeandwithoutincurringobligations.
PrintedinU.S.A.(05/04)
O’Fallon, MO