ICM Controls ICM333 - User Manual

2 pages

To Next Page

ICM333

Head Pressure Control with

Optional Heat Pump Override

Regulates head pressure via

temperature or pressure input

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

Caution!

Installation of the ICM333 shall be performed by trained technicians only. Adhere to all local and national electric codes. Disconnect all power to the system before making any connections.

• Line voltage:120,208,240,277,480and600VAC

• Control voltage:18-30VAC

• Frequency:50-60Hz

• Operating temperature:-40ºFto+176ºF(-40°Cto+75°C)

• Probes: –Temperature:Thermistor,10Kohmat77°F(25°C)

 –Pressure:ICM380(orderedseparately)

• Heat pump override:24VACN.C.orN.O.

• Weight:12ounces(341grams)

Speciﬁcations

Note: TheICM333shouldbeappliedtomotorsandequipmentthathavebeendesignatedbytheir

respectivemanufacturersascapableofbeingspeedcontrolled.

• Mounting:

 – Surfacemountusing(2)#8screws

 – TheICM333shouldbesurfacemountedtoacleanmetalorotherthermallyconductivesurface

formaximumheatdissipation

 – ItisrecommendedthattheICM333bemountedawayfromthecondenserexhaustairinorderto

maintainloweroperatingtemperatures

LIAF010-1

7313 William Barry Blvd., North Syracuse, NY 13212

(Toll Free) 800-365-5525 (Phone) 315-233-5266 (Fax) 315-233-5276

www.icmcontrols.com

ONE-YEAR LIMITED WARRANTY

TheSellerwarrantsitsproductsagainstdefectsinmaterialorworkmanshipforaperiodofone(1)

yearfromthedateofmanufacture.TheliabilityoftheSellerislimited,atitsoption,torepair,replace

orissueanon-casecreditforthepurchasepricesofthegoodswhichareprovidedtobedefective.

Thewarrantyandremediessetforthhereindonotapplytoanygoodsorpartsthereofwhichhave

beensubjectedtomisuseincludinganyuseorapplicationinviolationoftheSeller’sinstructions,

neglect,tampering,improperstorage,incorrectinstallationorservicingnotperformedbytheSeller.

InordertopermittheSellertoproperlyadministerthewarranty,theBuyershall:1)NotifytheSeller

promptlyofanyclaim,submittingdatecodeinformationoranyotherpertinentdataasrequestedby

theSeller.2)PermittheSellertoinspectandtesttheproductclaimedtobedefective.Itemsclaimed

tobedefectiveandaredeterminedbySellertobenon-defectivearesubjecttoa$30.00perhour

inspectionfee.ThiswarrantyconstitutestheSeller’ssoleliabilityhereunderandisinlieuofanyother

warrantyexpressed,impliedorstatutory.Unlessotherwisestatedinwriting,Sellermakesnowarranty

thatthegoodsdepictedordescribedhereinaretforanyparticularpurpose.

Example

1.Onlyoneprobetypecanbeusedatatime,temperatureorpressure.Uptotwo

probesofakindcanbeusedinwhichcasethecontrolwillrespondtotheprobe

thatsensesthehighesttemperatureorpressure.

2.AtypicalinstallationisshowninAppendix.Thetemperatureprobecanbe

attachedtotheU-bend.Usetheprovidedthermo-tapetosecuretheprobetothe

placeofattachment.

3.Whenusingapressureprobe,installitonthedischargelinetransducertting.

4.TemperatureandPressureprobesareconnectedtoICM333asshownin

respectivewiringdiagramsbelow.

Installing and Connecting the Probe

BLUE

WHITE

GREEN

RED

BLACK

PRESSURE TRANSDUCER

BLUE

WHITE

GREEN

RED

BLACK

PRESSURE TRANSDUCER

TEMPERATURE

PROBE

TEMPERATURE

PROBE

Connections for ICM333 at 120/208/240/277 VAC

1.Removepowerfromsystem.

2.FieldinstallawirefromLine 1wiretoLine 1terminal.

3.CutLine 2wire;afxmotorsidetoMotor 2terminal

andlinesidetoLine 2terminal.

4.Make24VACandtemperatureprobeconnections.

5.Verifywiringiscorrect.

6.Powerupsystemandcheckoperation.

Typical

condenser fan

PSC

Fan

Motor

Run

Capacitor

120/208/240/277

VAC

PSC

Fan

Motor

Run

Capacitor

Field

Installed

Wire

Line

120/277

VAC

Line

Motor

120/208/240/277

VAC

Connections for Heat Pump System at 120/208/240/277 VAC

1.Removepowerfromsystem.

2.FieldinstallawirefromLine 1wiretoLine 1terminal.

3.CutLine 2wire;afxthecommonfromthedefrost

board’sfanrelaytotheMotor 2terminalandtheLine

fromthecontactortotheLine 2terminal.

4.Make24VAC,probeandHPconnections.

5.Verifywiringiscorrect.

6.Powerupsystemandcheckoperation.

Field

Installed

Wire

PSC

Fan

Motor

Run

Capacitor

Fan

Relay

COM NC

Defrost Board

120/208/240/277

VAC

Line

120/240/277

VAC

Line

Motor

Connections for Heat Pump System at 480/600 VAC

1.Removepowerfromsystem.

2.FieldinstallawirefromLine 1wiretoLine 1terminal.

3.CutLine 2wire;afxthecommonfromthedefrost

board’sfanrelaytotheMotor 2terminalandtheLine

fromthecontactortotheLine 2terminal.

4.Make24VAC,probeandHPconnections.

5.Verifywiringiscorrect.

6.Powerupsystemandcheckoperation.

Connections for ICM333 at 480/600 VAC

1.Removepowerfromsystem.

2.FieldinstallawirefromLine 1wiretoLine 1terminal.

3.CutLine 2wire;afxmotorsidetoMotor 2terminal

andlinesidetoLine 2terminal.

4.Make24VACandtemperatureprobeconnections.

5.Verifywiringiscorrect.

6.Powerupsystemandcheckoperation.

Typical

condenser fan

PSC

Fan

Motor

Run

Capacitor

Line

Motor

Field

Installed

Wire

PSC

Fan

Motor

Run

Capacitor

Line

Motor

Field

Installed

Wire

PSC

Fan

Motor

Run

Capacitor

Fan

Relay

COM NC

Defrost Board

Questions and Answers

A
Austin MendozaAug 6, 2025
How to troubleshoot an ICM Controls Control Unit that fails to start?
- R
  raymond49Aug 6, 2025
  If your ICM Controls Control Unit fails to start, use an AC voltmeter to measure the voltage between the 24VAC terminals; it should be approximately 24 volts. Also, measure the line voltage between LINE1 and LINE2 to confirm that line voltage is present. If the lights are flashing alternatively, it indicates that no probe is connected or the probe is malfunctioning. For temperature probes, disconnect it and use an ohmmeter to measure the resistance between the wires, matching it with the chart in Appendix A. For pressure probes, with power applied, use a voltmeter to measure volts DC between COMM and P1 or P2, where the wire is connected, comparing the reading to the chart in Appendix B.
B
Brandi HerreraAug 21, 2025
Why does the fan cycle on and off with little speed modulation on my ICM Controls ICM333?
- R
  Robert WrightAug 21, 2025
  If the fan cycles from ON to OFF with little or no speed modulation in your ICM Controls Control Unit, reduce the hard start setting to the minimum needed to accelerate the fan. Excessive hard start causes large pressure drops by running too much cold air over the condenser. If cycling persists, relocate the temperature probe up the condenser to increase sensitivity to temperature change and/or adjust the temperature setpoint.

ICM Controls ICM333 Specifications

General

Power Supply	24 VAC
Output Voltage	24 VAC
Enclosure Material	Plastic
Certifications	UL Recognized
Operating Temperature	-40°F to +176°F (-40°C to +80°C)
Weight	0.5 lbs (0.23 kg)