4
Marvair MAA/MGA Wall Mount AC Installation & Operation Manual
09/2021 Rev.15
Chapter 5 Troubleshooting
5.1 Overview ................................................................................................................................................43
5.2 Failure Symptoms Guide ........................................................................................................................44
5.3 Compressor Troubleshooting .................................................................................................................44
5.4 Control Board Diagnosis ........................................................................................................................45
Chapter 6 Maintenance
6.1 Scheduled Maintenance .........................................................................................................................46
Chapter 7 Warranty
7.1 Airxcel Commercial Group Limited Product Warranty .........................................................................47
Chapter 8 Start-Up Checklist
8.1 Start-Up & Commissioning Form ..........................................................................................................48
Appendix A
Installation Instructions for Field Installed Electric Heaters ...........................................................................52
Illustrations
Figure 1a. Typical Electrical Schematic - Model MAA ..............................................................................12
Figure 1b. Typical Electrical Schematic - Model MAA ..............................................................................13
Figure 1c. Typical Electrical Schematic - Model MAA (Alternate Construction) .....................................14
Figure 1d. Typical Electrical Schematic - Model MAA (Alternate Construction) ......................................15
Figure 1e. Typical Electrical Schematic - Model MAA (Alternate Construction) ......................................16
Figure 2.
Dry Bulb sensor ..........................................................................................................................18
Figure 3.
Enthalpy Sensor Temperature Control Points ............................................................................19
Figure 4.
Electrical Controls, HVESA Alternate Construction .................................................................19
Figure 5.
Economizer Control Board ........................................................................................................20
Figure 6a. Setting the Speed for the Y1 and Y2 Operation for Indoor Motor ............................................23
Figure 6b. Second Stage Cooling Speed .....................................................................................................23
Figure 7.
Output Termination for Indoor Motor Control Signal ...............................................................24
Figure 8.
Outdoor Motor Speed Setting ....................................................................................................24
Figure 9.
Output Termination for Outdoor Motor Control Signal .............................................................24
Figure 10. Communications SetUp .............................................................................................................25
Figure 11. Fresh Air Hood Damper, Models 1024-1072 .............................................................................36
Figure 12. Wall Mounting Detail .................................................................................................................37
Figure 13a. Humidistat Wiring Details ..........................................................................................................40
Figure 13b. Thermostat Connection Diagram ...............................................................................................40
Figure 13c. CommStat™ 3 HVAC Controller Wiring Detail ........................................................................41
Figure 13d. CommStat™ 4 HVAC Controller Wiring Detail ........................................................................41
Tables
Table 1 CFM @ External Static Pressure .................................................................................................7
Table 2 Return Air Filter Sizes .................................................................................................................7
Table 3 Installed Unit Weights ..................................................................................................................7
Table 4 Ambient Temperature Operating Range ......................................................................................7
Table 5 Refrigerant Charge .......................................................................................................................8
Table 6. MODBUS Network Address DIP Switch Positions ..................................................................26
Table 7a. MODBUS Discrete Registers ....................................................................................................30
Table 7b. MODBUS Registers...................................................................................................................31
Table 8 Minimum Clearances .................................................................................................................33
Table 9 Voltage Limitations ....................................................................................................................33
Table 10 Maximum Static Pressure ..........................................................................................................36
