Air Conditioner Preventive Maintenance – How We Do It
Service Overview
- Average Cost: KES 3,000 – 6,000 per visit
- Service Frequency: Every 6 months (pre-summer and mid-season)
- Service Duration: 1.5-2.5 hours for comprehensive maintenance
- Benefits: 40% fewer breakdowns, 15-20% energy savings, extended equipment life
- Includes: Cleaning, adjustments, testing, minor repairs, detailed report
- Plans Available: Annual contracts with priority service
Preventive maintenance keeps air conditioners running efficiently while catching small problems before they become expensive failures. Our comprehensive maintenance service follows manufacturer guidelines and industry best practices, systematically inspecting, cleaning, and adjusting every component that affects performance and reliability.
Pre-Service Inspection and System History
We begin each maintenance visit by reviewing the system’s service history, noting previous repairs, recurring issues, and any modifications made since last service. This historical perspective helps us focus on areas requiring extra attention and track developing trends that might indicate impending failures.
Our initial inspection starts with the thermostat, verifying accurate temperature readings, proper mode operation, and that programming matches your needs. We check batteries in wireless thermostats and tighten any loose wall mounting. We then walk through the property, noting any comfort issues in specific rooms that might indicate airflow problems or duct issues requiring investigation.
At the outdoor unit, we observe the area around it, checking for vegetation encroachment, debris accumulation, or obstructions restricting airflow. We note any unusual sounds during startup and operation, signs of refrigerant leaks including oil stains, and general physical condition of the cabinet and components.
Electrical System Inspection and Testing
The electrical system receives thorough attention during maintenance as electrical problems cause many service failures. We inspect all visible wiring for damaged insulation, loose connections, or signs of overheating. Using a megohm meter, we test insulation resistance between power conductors and ground, identifying deteriorating insulation before it causes short circuits.
We measure voltage at the disconnect and at the unit terminals, verifying proper voltage under both no-load and full-load conditions. Low voltage causes inefficient operation and potential compressor damage, while excessive voltage stresses components. We check that voltage remains balanced between the two legs of 240V systems, as voltage imbalance causes motors to run hot and shortens their life.
Current draw measurements during compressor and fan operation tell us whether these components operate efficiently or draw excessive current suggesting developing problems. Amperage trending higher than previous measurements indicates deteriorating bearings, refrigerant problems, or other issues requiring investigation. We test capacitors using specialized meters, measuring actual capacitance and comparing it to rated values. Capacitors naturally degrade over time, and we replace any showing more than 10% deviation from specifications.
Contactor contacts are inspected for pitting or burning, cleaned if condition permits, or replaced if deterioration is advanced. We measure coil resistance and verify proper operation. Control board visual inspection identifies bulging capacitors, burned traces, or corrosion requiring attention.
Refrigerant System Checks
While detailed refrigerant system work exceeds basic maintenance scope, we perform key checks identifying problems requiring further service. We measure operating pressures on both high and low sides of the system, comparing them to expected values based on outdoor temperature and system type. Pressures outside normal ranges indicate refrigerant charge issues, airflow problems, or restricted refrigerant flow.
We measure superheat at the evaporator outlet and subcooling at the condenser outlet—these key indicators reveal whether the system holds proper refrigerant charge and operates efficiently. Incorrect values guide us toward specific problems like overcharging, undercharging, or metering device issues.
Visual inspection includes checking all accessible refrigerant connections for oil deposits indicating leaks. We inspect the line set insulation for damage exposing bare copper to the elements. We verify proper drainage from the evaporator coil, checking for standing water in the drain pan that suggests clogs. The expansion valve or capillary tube is inspected for frost formation indicating restrictions.
Comprehensive Cleaning
Cleaning represents one of maintenance’s most important aspects. The outdoor condenser coil receives particular attention as it accumulates dirt, pollen, leaves, and other debris that restricts airflow and reduces efficiency. We use specialized coil cleaning solutions and proper pressure washing techniques that remove embedded dirt without damaging the delicate fin surfaces.
After cleaning, we straighten any bent fins using fin combs matched to the coil’s fin spacing. Straightening fins restores proper airflow and improves appearance. We clean the area around the coil, removing leaves and debris from the base pan and checking that the weep holes drain freely.
The indoor evaporator coil also requires cleaning, though it typically stays cleaner than the outdoor coil. We access it through removable panels and clean the coil face using approved cleaning solutions and soft brushes that don’t damage fins. Heavily soiled coils may require professional coil cleaning equipment for thorough restoration.
The blower assembly is removed and thoroughly cleaned. Blower wheels accumulate thick layers of dust that reduce airflow and create imbalance causing vibration. We clean every blade surface, inspect the wheel for damage, and verify secure mounting. After cleaning, we lubricate the motor bearings if the motor design includes lubrication ports.
Filter Service and Airflow Optimization
We inspect and replace or clean air filters depending on type. Disposable filters are replaced with quality filters matching the system’s requirements—not so restrictive that they impede airflow but efficient enough to protect the equipment and improve indoor air quality. We mark the date on new filters and recommend appropriate replacement schedules based on your environment.
For homes with reusable filters, we clean them thoroughly using appropriate methods for the filter type. We inspect filter frames for damage and verify proper sealing when installed. Gaps around filters allow unfiltered air to bypass the filter, depositing dirt directly on coils and blower components.
We measure airflow across the evaporator coil when possible, comparing it to design specifications. Inadequate airflow causes numerous problems including reduced capacity, ice formation, and compressor damage from improper refrigerant return. If airflow is insufficient, we investigate causes including restrictive ductwork, undersized air handlers, or incorrect fan speed settings.
Calibration and Adjustment
Modern air conditioners include numerous adjustments affecting performance. We verify thermostat calibration using precision thermometers, adjusting the thermostat if it shows temperature errors. We check that temperature differentials between cycles match programming, preventing excessive short cycling or uncomfortably long run times.
We verify proper charge by carefully measuring temperatures and pressures, making small refrigerant adjustments when necessary to optimize performance. We adjust fan speeds if the system includes multi-speed capability, setting speeds appropriate for your ductwork and preferences. Some systems include adjustable expansion valves requiring periodic adjustment to maintain optimal superheat values.
Documentation and Recommendations
We provide detailed written reports documenting all findings, measurements, and work performed. Reports include photographic evidence of significant issues requiring attention. We prioritize recommendations, distinguishing between urgent repairs preventing system failure and efficiency improvements that reduce operating costs but don’t threaten immediate functionality.
Trending data from multiple maintenance visits reveals developing patterns. We track capacity degradation, efficiency changes, and component deterioration, predicting when major components will require replacement. This allows you to plan for expenses rather than facing unexpected failures during peak cooling season.
