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Eubank 7AA1024A-1060A & 7AA2036A-2060A I&O Manual 

07/2021 Rev.3

43

Chapter 5 Troubleshooting

5.1 Overview

A comprehensive understanding of the operation of the air conditioner is a prerequisite to troubleshooting. 

Please read the Chapter 1 for basic information about the unit. 
Eubank air conditioners are thoroughly tested before they are shipped from the factory. Although unlikely, 

it is possible that a defect may escape undetected, or damage may have occurred during transportation. 

However, the great majority of problems result from installation errors. 
If you experience difficulties with your unit, please review the installation steps in Chapter 2. 
Much time can be saved by taking a thoughtful and orderly approach to troubleshooting. Start with a 

visual check - are there loose wires, crimped tubing, missing parts, etc? Begin deeper analysis only 

after making this initial inspection.
The troubleshooting information in this manual is basic. The troubleshooting section contains problem/

solution charts for general problems, followed by a compressor section.
Not every problem can be anticipated. If you discover a problem that is not covered in this manual, we 

would be very grateful if you would bring it to the attention of our service department for incorporation 

in future revisions.
As always, please exercise caution and good judgement when servicing the unit. Use only safe and 

proven service techniques.  Use refrigeration goggles when servicing the refrigeration circuit.

 WARNING 

The refrigerant circuit has hot surfaces, and the electrical voltages inside of 

the unit may be hazardous or lethal. SERVICE MAY BE PERFORMED ONLY BY 

QUALIFIED AND EXPERIENCED PERSONS.

5.2  Failure Symptoms Guide

PROBLEM/SYMPTOM

LIKELY CAUSE(S)

CORRECTION

A. Unit does not run.

NOTE:  An internal anti-short-cycle 

timer will prevent the unit 

from starting for .2 to 8 

minutes following start-up.

1. Power supply problem. 

2. Tripped internal disconnect.

3. Shut off by external thermostat or 

thermostat is defective. 

4. Unit off on high or low pressure limit.

5. Internal component or connection 

failure.

1. Check power supply for adequate phase and voltage. 

Check wiring to unit and external breakers or fuses.

2. Check internal circuit protection devices for continuity.

3. Check operation of wall-mounted thermostat.

4. Reset pressure switch. 

5. Check for loose wiring. Check components for failure.

B. Unit runs for long periods or continu-

ously; cooling is insufficient.

1. Dirty filter or reduced airflow

2. Low refrigerant.

3. Component failure.

4. Unit undersized for job.

1. Check air filter(s). Check blower operation. Remove 

airflow restriction.

2. Check for proper charge and possible refrigerant leak.

3. Check internal components, especially compressor for 

proper operation.

4. Add additional units for greater capacity.

Summary of Contents for Eubank 7AA1024A

Page 1: ...n the unit being installed Refer to the unit data label or Model Identification to determine which features and options this unit is equipped with INSTALLER Affix the instructions on the inside of the...

Page 2: ...aying it down on its side may cause oil to leave the compressor and breakage or damage to other components 3 TURN ELECTRICAL POWER OFF AT THE breaker or fuse box BEFORE installing or working on the eq...

Page 3: ...the inside of the building adjacent to the thermostat END USER Retain these instructions for future reference Table of Contents Chapter 1 Eubank Wall Mount Air Conditioner Description Specifications 1...

Page 4: ...lpy Sensor Temperature Control Points 19 Figure 4 Electrical Controls Alternate Construction 19 Figure 5 Economizer Control Board 20 Figure 6a Setting the Speed for the Y1 and Y2 Operation for Indoor...

Page 5: ...ontrol board is in Section 1 6 All models are designed for easy installation and service Major components are accessible for service beneath external panels Allunitshaveinternaldisconnects optionalon3...

Page 6: ...2048A 1900 1850 1800 1700 1600 1500 1350 7AA2060A 1900 1850 1800 1700 1600 1500 1350 Values in bold are the minimum air flow Air flow ratings of 208 230 volt units are at 230v Air flow ratings of 460...

Page 7: ...ntrol FCC R Crank Case Heater CCH T Hard Start w EFS U Hard Start w Hot Gas Bypass V Hard Start w Low Ambient CCH EFS W Low Ambient w CCH X Hot Gas Bypass Y Low Ambient w CCH FCC Z Low Ambient w CCH E...

Page 8: ...or instructions on field installing electric heaters Economizer Operation Theeconomizerisaregulateddampersystemwithcontrols Thedamperregulatesthecirculationofoutside air into the enclosure when the ou...

Page 9: ...tective coating on exterior and interior components and sheet metal Note the internal sheet metal which is insulated bottom outside panel and the internal control box are not coated Hot Gas Bypass Non...

Page 10: ...is not common For harsh conditions e g power plants paper mills or sites were the unit will be exposed to salt water the condenser coil should be coated Note Cooling capacity may be reduced by up to 5...

Page 11: ...tal or only the exterior sheet metal 1 7 Electrical Operation The compressor and condenser fan are energized with a contactor controlled by a 24 VAC pilot signal Some compressors incorporate an intern...

Page 12: ...MRPESSOR CONTACTOR CAPACITOR C COMP CCH DFS CC OUTDOOR AIR MOTOR OUTDOOR FAN MOTOR OUTDOOR FAN RELAY REVERSING VALVE SOLENOID OFM PLC RVS OFR OAM FAN CYCLE CONTROL RELAY FAN CYCLE CONTROL FCCR FCC REH...

Page 13: ...CRANKCASE HEATER COMRPESSOR CONTACTOR CAPACITOR C COMP CCH DFS CC OUTDOOR AIR MOTOR OUTDOOR FAN MOTOR OUTDOOR FAN RELAY REVERSING VALVE SOLENOID OFM PLC RVS OFR OAM FAN CYCLE CONTROL RELAY FAN CYCLE...

Page 14: ...14 Eubank 7AA1024A 1060A 7AA2036A 2060A I O Manual 07 2021 Rev 3 Figure 1c Typical Electrical Schematic w Economizer Alternate Construction...

Page 15: ...Eubank 7AA1024A 1060A 7AA2036A 2060A I O Manual 07 2021 Rev 3 15 Figure 1d Typical Electrical Schematic w Economizer Alternate Construction...

Page 16: ...16 Eubank 7AA1024A 1060A 7AA2036A 2060A I O Manual 07 2021 Rev 3 Figure 1e Typical Electrical Schematic w Economizer Alternate Construction...

Page 17: ...changeover to outside air for free cooling The control board must be configured for proper operation of the economizer by selecting the desired changeover temperature The desired temperature is select...

Page 18: ...inimum Position Potentiometer W2 jumper The potentiometer controls the amount of outside air introduced in the building when the economizer damper closes or the air conditioner is Off or in Mechanical...

Page 19: ...currentlytheonlybrandofsensorsusedintheairconditioners Jumper W3 allows us to use alternative brands at a future date On all current air conditioners pins 1 2 are jumpered on W3 See item 4 in Figure 4...

Page 20: ...n Potentiometer 0 to 100 Factory setting is 50 2 Field connection from CommStat 4 2 terminal 5 For Honeywell sensors 8 W2 Minimum Position Potentiometer Jumper Jumper Pins 1 2 to Disable Factory setti...

Page 21: ...e information to the end user Special features include 2 Stage operation with varying speed control to optimize latent and sensible capacity built in remote communication MODBUS for monitoring and or...

Page 22: ...essure Switch LP Low Pressure Switch Switch to Be Closed for Cooling Operation Switch to Be Connected to R Node 16 24 VAC Power Input to PCB 17 Digital Outputs 24 VAC The PCB Makes and Breaks R RH Reh...

Page 23: ...ate signal terminations must be used This jumper will be factory installed In replacing the PCB verify the necessary signal and configure the board accordingly Only 2 of the 3 pins should be used for...

Page 24: ...tentiometer See figure below 3 1 2 1 Set for 0 10V Signal Jumper To Remain On The Appropriate Terminal For Correct Operation 2 Set For PWM Signal Jumper To Remain On The Appropriate Terminal For Corre...

Page 25: ...second The board also allows 15 different MODBUS addresses based on the position of the NET ADDRESS DIP switches The Net Addresses are written in Binary see table below with switch 4 being the least...

Page 26: ...mmissioning startupsequence to ensure safety and system reliability This document is only valid if the system is used as intended This section defines the manner and method of control of the HVAC syst...

Page 27: ...ollows 1 Stage 2 Cooling Request Y2 Input 2 Stage 1 Cooling Request Y1 Input 3 Electric Heat Request W2 Input 4 Dehumidification Request Hum Input 5 Indoor Fan Request G Input Note The priority list a...

Page 28: ...y Only CC1 output can achieve partial capacity Both CC1 and CC2 outputs are required to achieve full capacity Request Active Input Active Output Stage 1 Cooling 1 Fixed Compressor Y1 CC1 Partial Capac...

Page 29: ...ng operation In the event that the fault occurs a second time on the same call for cooling the system locks out To clear the fault the Cooling request must be cycled or the system must be power cycled...

Page 30: ...sor has to be configured via MODBUS Once configuration is complete the unit has the capability to function autonomously to maintain the space temperature Discrete Registers Read with Function Code 02...

Page 31: ...ng 16 Bit 1 60 default 25 represents minutes of allowed MODBUS inactivity before switching to onboard T Stat mode RW 10 Current OFM Speed 16 Bit 0 1023 RO 11 Current IFM Speed 16 Bit 0 1023 RO 12 Anti...

Page 32: ...r will not start makes excessive noise or will not pump return the unit to the freight carrier 3 2 Installation Requirements General 1 Inspect unit for completeness Check for missing parts e g hardwar...

Page 33: ...76 cm 18 inches 46 cm 24 inches 61 cm 6 inches 15 cm 1030A 1036A 2030A 2036A 30 inches 76 cm 18 inches 46 cm 24 inches 61 cm 6 inches 15 cm 1042A 1048A 1060A 2042A 2048A 2060A 30 inches 76 cm 30 inch...

Page 34: ...hange over Status LED s Backlit display Programmable fan Non volatile program memory P N 50107 Grilles Wall Sleeves Supply Grilles For 7AA1024A P N 80675 28 x 8 711 mm x 203 mm For 7AA1030A 1036A 1042...

Page 35: ...t instruments 3 4 Porting and Duct Work General Information Note The following instructions are for general guidance only Due to the wide variety of installation possibilities specific instructions wi...

Page 36: ...uld be used to simplify connections to duct work and grilles Use fabric boots to prevent the transmission of vibration through the duct system The fabric must be U L rated to a minimum of 197 F 92 C M...

Page 37: ...e wall You must stabilize the unit on the bracket with the lifting device or by some other means the bracket alone is not sufficient 3 Make sure that the duct flanges are properly aligned with the wal...

Page 38: ...stem with small critical refrigerant charges where the installation of gauges may be objectionable can be made by monitoring the temperature of the refrigerant lines at the compressor The temperature...

Page 39: ...wer leads connected to the internal circuit breaker on one of the units only D Restore power and retest the phase step B When the voltage reads 0 the units are in phase E Turn off power and proceed Lo...

Page 40: ...air conditioning system for a telecommunication cabinet or shelter The CommStat 3 Controller is factory programmed with standard industry set points to facilitate installation If desired each of the s...

Page 41: ...Contacts NC C NO High Building Temp Alarm Dry Contacts NC C NO 5 Connect to Normally Closed NC dry contacts from smoke alarm SMOKE ALARM JUMPER NOTE IF LINE VOLTAGE IS BELOW 220 VAC USE THE 208 TRANSF...

Page 42: ...izer Equipped models only To check the system operation under different ambient conditions the air temperature and enthalpy sensors must be tricked When outdoor ambient condi tions are higher than the...

Page 43: ...ase exercise caution and good judgement when servicing the unit Use only safe and proven service techniques Use refrigeration goggles when servicing the refrigeration circuit WARNING The refrigerant c...

Page 44: ...improper connection in field wiring 3 Internal short circuit Loose or improper connection s in unit 4 Excessively high or low supply volt age or phase loss 3 only 1 Note electrical requirements in Ch...

Page 45: ...leakage with a megoh meter Attach one lead to the compressor case on a bare metal tube and to each compressor terminal to test the motor windings A short circuit at high voltages indicates a motor def...

Page 46: ...ed before restarting Condenser Periodicallyinspecttheoutdoorcondensercoilandthecabinetairreliefsfordirtorobstructions Remove foreign objects such as leaves paper etc If the condenser coil is dirty it...

Page 47: ...y other material charges 2 Damages caused by shipping accident abuse negligence misuse fire flood or Acts of God 3 Damages caused by operating or staging the unit in a corrosive environment 4 Damages...

Page 48: ...______________________ Compressor Model No ______________________________________________ Serial No ______________________________________________ B Pre Start Up Is there any shipping damage Yes No If...

Page 49: ...ion from avg voltage ______________volts Voltage imbalance 100 x Max Deviation avg Voltage ___________ A voltage deviation greater than 2 with the unit running should be addressed and corrected Excess...

Page 50: ...emp ________ ________ Evap Leaving Air WB Temp ________ ________ Heater Contactor Amps L1 ________ ________ Heater Contactor Amps L2 ________ ________ Heater Contactor Amps L3 ________ ________ E Cool...

Page 51: ...ressor Amps L3 ________ ________ Notes _________________________________________________________________________ _________________________________________________________________________ _____________...

Page 52: ...on all four sides of the supply outlet duct flange on the unit The 1 25 4 mm clearance must extend on all sides of the supply duct for the first 3 feet 1 meter from the unit IMPORTANT Eubank requires...

Page 53: ...other heaters 6 Install the two No 10 screws in the heater assembly plate 7 Install wire harness in hole provided in drain pan and then through filter bracket and then into control box 8 Wire the heat...

Page 54: ...54 Eubank 7AA1024A 1060A 7AA2036A 2060A I O Manual 07 2021 Rev 3...

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