User Guide

ICM2918
Gas Ignition Control
Installation, Operation & Application Guide
For more information on our complete range of American-made
products – plus wiring diagrams, troubleshooting tips and more,
visit us at www.icmcontrols.com
Low cost,
replacement
ignition control
• Universal intermittent pilot gas ignition
control
• Patented circuitry for enhanced operation
• Providesignitionsequence,amemonitoring
and safety shutoff for single/dual rod
intermittent pilot control applications
• Forgasredfurnaces,boilersandother
heating applications
• Switchselectablepre-purgeandignitiontrials
with permanent lock
• Works with or without vent damper connected
• WorkswithbothNaturalandLPgassystems
ICM2918 Settings and Adjustments
Wiring DiagramsMounting and Installation
Pilot COM
Main
Valve
1st
Operator
Dual Valve Combination
Gas Control
Limit
Controller
Wiring
Harness
Vent
Damper
Thermostat
Pilot Burner/
Igniter
2nd
Operator
Ground
Pilot Gas Supply
MV
MV/
PV
PV
GND
(BRN)
24V
GND
24V TH-W P1
REMOTE
SENSOR
SPARK
L1 (Hot)
L2
Jumper
Wire
ICM2918
atmospheric burner / vent damper
Pilot COM
Main
Valve
1st
Operator
Dual Valve Combination
Gas Control
Limit
Controller
Pilot Burner/
Igniter
2nd
Operator
Ground
Pilot Gas Supply
MV
MV/
PV
PV
GND
(BRN)
24V
GND
24V TH-W P1
REMOTE
SENSOR
SPARK
L1 (Hot)
L2
Jumper
Wire
ICM2918
atmospheric burner / no vent damper
Two Rod
Remote
Sense
Jumper wire clipped
close to board
Sensor wire from igniter
sensor
Pilot COM
Main
Valve
1st
Operator
Dual Valve Combination
Gas Control
Limit
Controller
Combustion
Air Blower
Motor
Combustion
Air Blower
Relay
Air
Proving
Switch
Pilot Burner/
Igniter
2nd
Operator
Ground
Pilot Gas Supply
MV
MV/
PV
PV
GND
(BRN)
24V
GND
24V TH-W P1
REMOTE
SENSOR
SPARK
L1 (Hot)
L1
(Hot)
L2
L2
Jumper
Wire
Thermostat
ICM2918
power-assisted combustion
1
Power supply – provide disconnect means and overload protection as required.
2
Alternate limit controller location.
3
Maximum cable length: 3 Ft. [0.9 M].
4
Controls in 24V circuit (NOTE: must not be in ground leg to transformer).
5
Substitute board plug with damper plug in a system with a vent damper.
6
Jumper Wire:
For single rod applications: connect to remote sense connector.
 Fordualrodapplications:remove(clipasclosetoboardaspossible)anddiscard;rmlyattachsensorwirefromtheigniter/sensorassemblytoremotesenseconnector.
IMPORTANT: Reinstallingthejumperonceithasbeenremovedand/orthe
DIPswitchsettingshavebeenlockedwillnotresettheDIP
switchsettings.
Jumper Actiontolockthecontrol’soperatingsequence
P4 The P4 Jumper locks in the operating sequence selected by
the DIP switch settings. Following installation and checkout,
pull the P4 jumper to lock the DIP switch settings and ensure
proper system operation.
Note: Forsafety,theignitioncontrollockstheDIPswitch
settingsafterthe10th“heatcall”cycleregardlessof
thejumperbeingremoved.
S1 DIP Switch 2
S1 DIP Switch 1
P4 Jumper
Note: Thedefaultfactorysettingsareinbold.
Prepurge TrialForIgnition SW1 SW2
None 90 seconds OFF OFF
30 seconds 90 seconds ON OFF
None 15 seconds OFF ON
30 seconds 15 seconds ON ON
Prepurge and Trial for Ignition Parameters
• Table to the right displays preferred times for Prepurge (SW1) and Trial for
Ignition (SW2).
DIP Switch (S1)
Factory preset as
shown (OFF) for
SW1 and SW2.
S1
ON
1 2
Operation
Flame and Status LED Locations
The ICM2918 has two LEDs; one for ame sensing (Yellow) and one for system status (Green). Refer
to the Flame Code charts on the reverse side of this application for more details.
Flame LED
Status LED
• If possible, mount the ICM2918 control in the same position and using the same mounting
holes as the unit you are replacing. If you need to reposition the control, mount the
ICM2918 using four screws and at a distance no greater than 3 ft. away from the pilot
burner and in a place that allows for the most direct spark cable route.
• Connect the thermostat wire (used for a heat call) to the TH-W terminal. The heat call
powers the unit.
• Connect common from the control transformer to 24V GND terminal
• Make the remaining PV, MV/PV and MV gas control connections to the appropriate
terminals on the control module
• Sparkcablespecications
– Spark Cable Length: 36” maximum
– Spark Cable Voltage Rating: >10,000 (preferably higher)
– To ensure maximum spark voltage, plastic or ceramic insulators should be used to
ensure the spark cable does not come in direct contact with a metal surface
– If necessary, use the Rajah adapter to make the connection to the spark terminal on the
control module
– For added safety, both ends of the spark cable should be protected with insulated boots
• Grounding
– Make a ground connection from burner bracket mounting screw to BRN GND terminal
on the board
• Burner
– Ensure that the spark gap is close to 1/8 in.
• Pilotame
– Make sure it is blue, steady and envelopes 3/8 to 1/2 in. of the ame rod. If necessary
adjust pilot ame by turning the pilot adjustment screw on the gas control
• Damper
– If part of the system, plug the damper cable to P1 connector on the control module
– If the plug is removed and the vent damper connector is plugged in instead, then an
internal fuse will blow on power up. The control will not operate without a vent damper
or with the plug.
– Connect 24 VAC hot from the control transformer to 24V terminal on the control module
when the Damper assembly is used
1
4
2
3
5
6
1
4
2
3
5
6
1
4
2
3
5
6
6
Specifications
OperatingTemperature:
– Minimum ambient temperature rating is -40°F (-40°C)
– Maximum ambient rating when used with 2.0 A main valve is 165°F (74°C)
StatusLEDs:
– Green Status provides system status and error codes
– YellowFlameLED indicates ame presence and ame strength
ControlVoltage: Line 24 VAC (18-30 VAC) 50/60 Hz
FlameCurrent: Typical
AnticipatorSetting: 0.3 A plus valve load @ 24 VAC
TrialforIgnition: See Table 1 on reverse side
Prepurge: See Table 1 on reverse side
FlameFailureResponseTime: 2 seconds maximum
TypicalGasControl: Honeywell models VR8204 and VR8304
RelativeHumidity: 0% to 95% non condensing
Note: TheICM2918amesensoroperatesoffof24VACdirectly;amecurrentsoflessthanone
microamperearetypical.
Application
The ICM2918 Universal Intermittent Pilot Gas Ignition Control Module replaces many popular
ame rectication type of intermittent pilot ignition (IPI) modules, including those manufactured by
Honeywell, Robertshaw, and Johnson Controls. Replaces modules that feature:
• Natural or LP gas
• With or without integral damper connector
• Non-100 percent shutoff, 100 percent shutoff/lockout, or 100 percent shutoff/continuous retry
• Pilot burners with ow rates of 1,500 Btu/h or less
• Single (local sense) or dual (remote sense) rod ame sensing
• Shutoff/lockout times of 15 seconds or longer
• Prepurge congurable to 30 seconds or no prepurge
For more details on the key features included in the ICM2918 control, as well as a cross reference list
of controls that the ICM2918 will replace, please see Table 1 and Table 2 on the back of this guide, or
visit our web site at www.icmcontrols.com.
Package Contents
The following is included in the package with the ICM2918 control:
• Easy-to-use instructions
• Accessories required to adapt the existing spark cable (Rajah adapter) to the spark terminal on the
control module
• Fault code LED label to afx to the appliance
The ICM2918 control also features the following:
• High voltage spark, pilot burner ignition control
• Flame rectication circuit for monitoring ame presence
• Monitoring of 24 VAC, pilot, and main gas valve
• Two status LEDs to aid in operation and troubleshooting
• Vent damper connection
MainBurnerOperation
1. The main valve opens, allowing gas to ow to the main burner.
Here, the pilot ame ignites the gas.
Note: Ashortdelayoccurswhenmainvalveopensinorder
toallowthepilotametostabilizeasthemaingas
lights.
2. With the system in run mode, the ame rectication circuit will
continuously monitor for the presence of the pilot ame.
3. In the event of pilot ame loss, the ICM2918 will shut off both
the pilot valve relay and the main valve relay for 100% gas
shutoff.
FailedTrialforPilotIgnition
1. The ICM2918 is designed to operate with multiple trials for
ignition (TFI).
2. When no pilot ames is sensed during the TFI period, the
ignition control shuts off the spark and pilot gas (100% shutoff).
3. The control will enter a ve-minute lockout period before the
next TFI cycle will begin.
Note: ContinuousTFIattemptswillbemadeuntilaameis
sensedorthecallforheatissatised.
While NOT recommended, the ve-minute lockout period can
be bypassed by manually ending the call for heat or removing
and restoring system power.
TrialforPilotIgnition
1. When the thermostat initiates a call for heat, the spark source
and the pilot valve relay become energized.
2. The pilot valve opens; gas ows to the pilot burner for the
ignition trial time.
3. The control module initiates a spark and attempts to light the
pilot ame.
4. A ame rectication circuit checks for the presence of the pilot
ame.
5. Upon ame detection, the spark source is shut off and the
main valve relay is energized.
ICM2918 Typical Wiring Connections
TH-WTerminal
24 VAC / Hot connector for heat call signal from thermostat
24VTerminal
Optional: 24 VAC power connection for vent damper
24VGNDTerminal
Return path to transformer
GNDTerminal
Burner ground
PVTerminal
Pilot valve connection
MV/PVTerminal
Common terminal for gas valves
MVTerminal
Main valve connection
P1 Connector
Connector for vent damper connection (used to control a connected damper in atmospheric appliances)
Spark Ignitor
High voltage sparking electrode
Sense Jumper Wire
Connects to
REMOTESENSE connector for single
rod installations (local ame sensing)
Note: Forremoteamesensinginstallations
(separatesparkandsensorrods),clipthe
jumperwireasclosetothecircuitboard
as possible and remove.
Remote Sense
Flame Sensor connector
• For single rod installations:
connect the SENSE JUMPER WIRE
to this terminal connector.
• For dual rod installations:
connect FLAME SENSE WIRE from
the burner/igniter to this terminal
connector
P4 (Jumper)
Locks out DIP switch settings
(See “Setting and Adjustments
at the right”.)
Settings and Adjustments
DIPSwitch(S1)Settings:
• Many ignition controls may be replaced with the ICM2918 control. The DIP
switch settings for the most popular competitive models can be found in
Table 2 on the reverse side of this guide.
• The table to the right shows lockout control of DIP switch timing settings.
• WARNING: Ignition control should not be powered before setting the DIP
switches.
Certified to
ANSI Z21.20
DANGER!
Onlytrainedpersonnelshouldinstallorserviceheatingequipment.Whenworkingwithheating
equipment,besuretoreadandunderstandall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.
CAUTION!
Failuretoturnoffgasandelectricsuppliescanresultinexplosion,re,personalinjuryordeath.