Copyright Goodheart-Willcox Co., Inc. Chapter 32 Residential Split Air-Conditioning Systems 813 10 7. Inspect and clean the blower. Lubricate the motor as appropriate. If the fan is belt-driven, inspect the belt and pulleys for wear. Check the belt for proper tension. 8. Inspect the refrigerant lines and connections for damaged insulation, signs of leaks, or other damage. 9. Inspect all ductwork for leaks and broken dampers. Make sure that all supply ducts and returns are not obstructed and that sufficient airflow is observed. 32.5.2 Troubleshooting Central Air- Conditioning Systems Many service calls are initiated by unexpected problems. In these cases, the air-conditioning system is not oper- ating properly. The homeowner observes a problem and requests service. There are several possible causes of comfort cooling– related service calls: • No cooling or insufficient cooling. • Indoor air too humid. • Air in building is stuffy (stale). • Excessive (indoor or outdoor) noise. • High cost of operation. • System will not start. Educating Your Customer An annual maintenance service visit provides an opportunity to educate the homeowner about how the air-conditioning systems operate, the value of maintenance, and any specific indicators of problems that the homeowner can monitor. Pro Tip When servicing a system with an unknown root cause, use a systematic troubleshooting procedure. The general systematic troubleshooting procedure shown in Figure 32-25 was introduced in Chapter 3, Service Calls. The following are the steps in this general procedure: • Customer interview. The customer may be able to provide information that will help you troubleshoot the system, but you must ask the right questions. Figure 32-26 lists some sample questions that may result in useful information. • Initial inspection. Often, the initial inspection will provide clues to the cause of the problem or at least to potential issues with the system. As you perform the initial inspection, consider the three subsystems of an air-conditioning system: airflow, electrical, and mechanical/refrigerant. • Identify system malfunction, test to find cause. The initial inspection may reveal or suggest system malfunctions. Use equipment-specific troubleshooting charts, wiring diagrams, and other service material to help pinpoint potential faults. Algaecide tablets DiversiTech Corporation Figure 32-24. Placing algaecide tablets in the condensate drain pan. Understanding Correct System Operation • Expected measurements • Sequence of operation Subsystem Considerations • Airflow • Electrical • Mechanical/refrigerant • Combustion Resources • Equipment troubleshooting codes • Equipment troubleshooting charts • Equipment wiring diagrams • Equipment service information General Systematic Troubleshooting Procedure Customer Interview Initial Inspection Identify System Malfunction, Test to Find Cause Repair Test System for Proper Operation Troubleshooting Steps Informed By: Goodheart-Willcox Publisher Figure 32-25. This general troubleshooting procedure can be used to service any HVACR system, including air-conditioning systems. A thorough understanding of proper system operation is critical for successful troubleshooting.