ICM Controls ICM291 - User Manual

7313 William Barry Blvd.
North Syracuse, NY 13212
ICM CONTROLS 800.365.5525
www.icmcontrols.com
LIAF098-1
Install New Control
1. Groundyourself.Whenhandlingcircuitboard,holditbytheedges.
2. Fastencircuitboardwithretainingscrews.
3. Connectalllinevoltage,lowvoltage,andaccessorywires.
4. Verifythesequenceofoperation.
Safety Considerations
Onlytrainedpersonnelshouldinstallorserviceheatingequipment.Whenworkingwithheating
equipment,besuretoreadandunderstandallprecautionsinthedocumentation,onlabels,andon
tagsthataccompanytheequipment.Failuretofollowallsafetyguidelinesmayresultindamageto
equipment,severepersonalinjuryordeath.
Introduction
TheICM291DSIgasignitioncontrolreplacesthefollowingCarriermodel:LH33WP003A.The
ICM291hasincorporatedLEDdiagnosticstoassistintroubleshooting.Faultcodeinformationcanbe
foundinthisapplicationguide.Pleasekeepthisapplicationguidewiththefurnaceinstallationmanual
forfuturereference.
Electrostatic Discharge (ESD) Precautions
CAUTION!
Use caution when installing and servicing the furnace to avoid and control electrostatic discharge;
ESD can impact electronic components. These precautions must be followed to prevent
electrostatic discharge from hand tools and personnel. Following the precautions will protect the
control from ESD by discharging static electricity buildup to ground.
1. Disconnectallpowertothefurnace.Donottouchthecontrolorthewiringpriortodischargingyour
body’selectrostaticchargetoground.
2. Togroundyourself,touchyourhandandtoolstoaclean,metal(unpainted)furnacesurfacenear
thecontrolboard.
3. Servicethefurnaceaftertouchingthechassis.Yourbodywillrechargewithstaticelectricityasyou
shufeyourfeetormovearound,andyoumustregroundyourself.
4. Regroundyourselfifyoutouchungroundeditems.
5. Beforehandlinganewcontrol,regroundyourself;thiswillprotectthecontrol.Storeusedandnew
controlsinseparatecontainersbeforetouchingungroundedobjects.
6. ESDdamagecanalsobepreventedbyusinganESDservicekit.
CAUTION!
To service control, and prior to disconnection, label all wires. Failure to do so may result in wiring
errors that can cause dangerous operation.
1. TurnthermostattoOFFpositionorsetittothelowestpossiblesetting.
2. TurnOFFelectricalsupplytofurnace.
3. TurnOFFgassupplytofurnace.
CAUTION:Failuretoturnoffgasandelectricsuppliescanresultinexplosion,re,death,or
personalinjury.
4. Removefurnaceblowerandcontrolaccessdoors.
5. Disconnectthermostatwiresandhumidierwires(ifequippedwithahumidier).
6. Disconnectlinevoltage,blower,electronicaircleanerwires(ifequipped),andtransformerwires.
7. Removescrewsandanyotherfasteners,andtheoldcircuitboard.
8. Examinecontrolandcontrolboxtocheckforwaterstains.
9. Makerepairsifanysourcesofwaterleakagearefound.Besuretocheckhumidiers,evaporator
coils,andventsystemsintheareaofthecontrol.
Remove Existing Control
ICM291 Gas Ignition Control Board
AWcallfromtheT’statwillengagethecombustionmotor.Ignitionsequencebegins,gasvalveand
sparkareengaged,providingthatsystemsafetyswitches(RS,LS,andCS)areclosedandthereis
feedbackfromthecombustionmotorHallEffectsensor.Theblowerandindoormotorswillengage45
secondsafterameisestablishedandsensed.Theydisengage45secondsafterWcallissatised.
AGcallfromtheT’statwillengageblowerandindoormotorsrightaway.Theydisengage25seconds
afterGcallisremoved.
Sequence of Operation
Flame not established
1. Ifameisnotestablishedduringthe5+2initialsequencethenthecontrolwillstartthenexttrialfor
ignitionin20seconds.
2. Theattempttoignitewillcontinuefor15minutesbeforetherespectivefaultcodeistriggeredand
ignitiontrialsarestopped.
3.Thegasvalveisenergizedonlyduringtheignitionsequenceof5+2seconds.
4. Blowerandindoorfanmotorsareoffuntilameisestablishedand45secondslater.
Flame out
1. Flameoutisconsideredwhenameislostduringheating.
2. WhenWsignalispresentandameissensedoutthenthesparkwillstartrightaway.
3. Ifameisnotestablishedontheimmediatesequence(2above)thenthecontrolwillcontinue
attemptsevery20secondsfor15minutesbeforetherespectivefaultcodeistriggeredandignition
trialsarestopped.
4. Blower&indoorfanmotorswillcontinuerunningduringameoutscenariofor15mins.+45secs.
5.Combustionmotorremainsonthroughouttheameoutscenario.
Flame out of sequence
1. FlameoutofsequencerepresentsascenariowhenameissensedwhileWsignalisnotpresent.
2. Combustion,blowerandindoorfanmotorswillbeengaged(ifnotalreadyrunning)rightawayand
keeprunningforaslongasthefaultconditionispresent.
3. Theunitisoperablebutwilldisplaythefaultcodeconstantlyuntilreplacedbyanotherfaultcodeor
powerreset.
No signal from the Hall affect sensor
1. OnaWcall,iftheinputfromtheHallaffectsensor(RA0)isnotpresentformorethanaminute,
thenthecombustionmotorwillcontinuerunningendlesslyandtherespectivefaultisashed.
2. DuringrunningstateiftheinputfromtheHallaffectsensorisnotsensedthenthegasvalvewill
shutoffrightaway,blowerandindoorfanmotorswillcontinuerunningfor30secondsandthen
turnoff,combustionmotorrunscontinuously.
Troubleshooting Tips
LED Fault Codes
# Of Flashes
represents Constant
ON Normal operation
Results
1
Thecontrolhasmodiedthefanondelayto0andoffdelayto3mins.
duetosensingLStripwithin10minutesofacall
2
a) LSisopenduetohightemperature(fanisn’tworkingscenario)
b) Theunitwillnotstartatrialforignitionuntiltheswitchclosesback
3
a) Flamesensedoutofsequence.
b) Theunitisoperable,howeverwilldisplaythisfaultcodeuntilpower
resetoranothercode
4
a) LSopened4consecutivetimesduringacallforheating
b) ThefaultcodeisresetonthenextWcall
5
a) Ignitionlockout.Thecontroltriedunsuccessfullytoignitefor15mins.
b) Theunitwillnotoperate.Requirespowerreset
6
a) ThecombustionmotorisnotsensedrunningORCSopen
b) Theunitwillnotoperate.Requirespowerreset
7
a) RStripped
b) Theunitwillnotoperate.Requirespowerreset
8 a) Unusualgasvalveresponse
FEATURES
• Direct Spark Ignition (DSI) control board
• Microprocessor-based
• Controls combustion, blower and indoor motors; spark ignitor; and the gas valve
• Monitors timing, trial for ignition, ame sensing and lockout
• 100% lockout safety feature
• Compatible with LP or Natural Gas
• Status LED for fault codes to aid in troubleshooting
• Replaces: Carrier LH33WP003A
SPECIFICATIONS
• Control voltage:24VAC(18-30VAC),60Hz
• Line voltage:208/230VAC,60Hz
• Power consumption:0.3Aplusgasvalvecurrentat24VAC
• Operating Temperature:-40°C(-40°F)to75°C(176°F)
LED indicators
• Red LED: SteadyON-normaloperation
  Flashing-faultcodes
Timing
• Pre-purge:45seconds
• Trial for Ignition:5+2seconds
• Retry period:every20sec.for15min.
• Lockout:manualreset
• Post-purge:45seconds
Inputs
• Power:RTandC
• Thermostat interface:R,WandG
• Safety switches:RS,LS,andCS
• CombustionmotorHallEffectsensor
• FlameSensing
Outputs
• Spark
• Gas Valve:GV
• Combustion motor:CM
• Blower motor:BM
• Indoor fan motor:IFO

ICM Controls ICM291 Specifications

General

Weight	0.4 lbs
Status Indication	LED
Prepurge	30 seconds
Terminal Type	Screw Terminals
Operating Temperature	-40°F to 175°F
Ignition Retries	3
Mounting	Surface Mount
Type	Universal Ignition Control Module
Ignition Type	Direct Spark Ignition (DSI)

Summary

Safety Considerations

Introduction to ICM291 Control

Electrostatic Discharge (ESD) Precautions

Remove Existing Control

Specifications

Troubleshooting Tips

Flame Not Established Troubleshooting

Guidance on ignition trial sequences, gas valve operation, and blower motor engagement when flame is not detected.

Flame Out Troubleshooting

Procedures and behavior when flame is lost during heating, including spark restarts and motor operation.

Flame Out of Sequence Troubleshooting

Handling scenarios where flame is sensed without a W signal, motor engagement, and fault code display.

Hall Effect Sensor Signal Issues

Troubleshooting steps for a missing Hall effect sensor signal, including motor behavior and gas valve shutdown.

LED Fault Codes

LED Fault Code 1

Fan on/off delay modified due to LS trip, unit may not start ignition until switch closes.

LED Fault Code 2

Flame sensed out of sequence; unit operable but displays code until reset or another code.

LED Fault Code 3

LS opened 4 consecutive times during a call for heating; fault resets on next W call.

LED Fault Code 4

Ignition lockout: control attempted ignition unsuccessfully for 15 mins.

LED Fault Code 5

Combustion motor not sensed running or CS open; requires power reset.

LED Fault Code 6

RS tripped; unit will not operate and requires power reset.

LED Fault Code 7

RS tripped; unit will not operate and requires power reset.

LED Fault Code 8

Unusual gas valve response; requires power reset.

Sequence of Operation

Typical Wiring Diagram

Testing the Inducer Motor