Residential Air Conditioning Guide

by | Jun 1, 2023

A residential air conditioning guide feels appropriate after one of the hottest months of May we’ve experienced in recent years. However, it wouldn’t be a surprise to find most Calgary homeowners have already kicked their air conditioners back into action. Perhaps you’re one of the few who’s waited until June to flip the AC on. Better yet, maybe the May heat was enough to make you decide this is the year you finally purchase a unit. Either way this residential air conditioner guide will help as you get familiar with the units, and ensure yours is up and running this summer.

A Complete Guide to Air Conditioners from Your Calgary Home Inspector

Benefits of Residential Home Air Conditioners

  • Air conditioners have become an essential appliance in many residential homes, providing comfort during hot summer months. These units provide numerous benefits beyond just lowering the air temperature. Here are some key advantages of having an air conditioner at home:

    1. Improved Comfort: Air conditioners provide relief from excessive heat and humidity, creating a cool and comfortable indoor environment for relaxation.


    2. Enhanced Indoor Air Quality: Advanced air conditioning systems filter out dust, pollen, and other airborne particles, improving the overall air quality inside your home.


    3. Health Benefits: By reducing indoor humidity, air conditioners help prevent the growth of mold, mildew, and dust mites, which can trigger allergies and respiratory issues.


    4. Increased Productivity: Maintaining a cool and comfortable temperature helps improve focus, concentration, and overall productivity, especially during hot summer days.


    5. Better Sleep: Air conditioners enable you to sleep comfortably by regulating the temperature and reducing humidity, ensuring a good night’s rest.

How Residential Air Conditioners Work

  • Your typical air conditioner consists of a compressor, condenser, evaporator, and expansion valve. Each component plays a vital role in the cooling process.

    The compressor, often referred to as the “heart” of the air conditioner, circulates refrigerant throughout the system. It compresses low-pressure, low-temperature refrigerant vapor, transforming it into high-pressure, high-temperature gas. This gas then flows into the condenser.

    The condenser facilitates heat transfer by dissipating heat from the refrigerant to the surrounding environment. As the high-pressure gas cools down, it condenses into a high-pressure liquid. This liquid refrigerant then moves into the evaporator.

    In the evaporator, the liquid refrigerant undergoes a phase change, transforming into low-pressure gas. The evaporation process absorbs heat from the indoor air, reducing the temperature within the space. The cooled air is then distributed throughout the house, while the low-pressure gas returns to the compressor to repeat the cycle.

    The expansion valve regulates the flow of refrigerant between the evaporator and the condenser. It creates a pressure drop, allowing the refrigerant to expand and cool rapidly in the evaporator, thus facilitating efficient heat exchange.

  • In layman’s terms when you run an air conditioner you are actually removing existing heat from a space, not introducing cold air into it. Once inside the house the “super-cooled” refrigerant works with the evaporator to attract heat from the air. This heat energy warms the refrigerant. It then moves back to the exterior condenser to release the absorbed heat energy into the atmosphere before the compressor restarts the cycle. The cool air you feel coming out of your registers is air that has lost its heat energy and is now being recirculated.

Types of Residential Home Air Conditioners

  • When choosing an air conditioner for your home, it’s essential to consider the different types available. Each type has its own set of features, installation requirements, and cooling capabilities. Here is a residential home air conditioners guide for some of the more common types:


  • Central air conditioners are a popular choice for cooling large homes. They consist of two main components: an outdoor unit and an indoor unit. The outdoor unit houses the compressor and condenser, while the indoor unit contains the evaporator and air handler. Central air conditioners use ductwork to distribute cool air throughout the house, ensuring consistent and even cooling. Meaning a central air conditioner will use the home’s existing duct system that’s used by the furnace for heating.


  • Ductless mini-split systems are an excellent option for homes without existing ductwork or for individual room cooling. Mini-split systems are a common means for cooling condo or apartment units. They consist of an outdoor unit and one or more indoor units, which are mounted on the wall or ceiling. Ductless systems allow for zoned cooling, enabling you to set different temperatures in different areas of your home. 


  • Then there’s the good old fashion clunky window air conditioners. These are a cost-effective and easy-to-install cooling solution for single rooms. A window air conditioner may also be appropriate when you’re unable to make changes to the building, such as a if you’re a rental tenant. They are typically installed in a window frame or a specially designed opening in the wall. These units contain all the necessary components in a single housing, including the compressor, condenser, evaporator, and air filter.


  • Portable air conditioners offer flexibility and mobility, allowing you to move them from room to room as needed. They come with an exhaust hose that needs to be vented out of a window or through a wall. Portable units are suitable for smaller spaces and are a temporary cooling solution.

Residential Air Conditioner Observed during a Home Inspection; Found to be in Good Condition
Mini-Split Air Conditioner Inspection Guide
AC Unit Inspection
Interior Air Conditioner Inspection

Factors to Consider When Choosing a Residential Home Air Conditioner

  • When selecting a residential home air conditioner, there are a few factors to keep in mind. These considerations will help ensure that you choose the right unit that suits your specific needs and requirements. Here are some factors to consider:


    1. Cooling Capacity: The cooling capacity of an air conditioner is measured in British Thermal Units (BTUs). It determines the unit’s ability to cool a specific area. Assess the size of the space you need to cool and choose an air conditioner with the appropriate BTU rating. BTU’s are the same unit of measure used by heating systems.


    2. Energy Efficiency: Energy-efficient air conditioners can significantly reduce your energy consumption and lower your utility bills. Look for units with high Energy Efficiency Ratio (EER) or Seasonal Energy Efficiency Ratio (SEER) ratings.


    3. Noise Levels: Consider the noise levels of the air conditioner, especially if you plan to install it in a bedroom or living area. Look for models with lower decibel ratings for quieter operation. Similarly, if the unit is to be located outside aim to have it installed away from sleeping quarters where feasible.


    4. Installation Requirements: Different types of air conditioners have varying installation requirements. Ensure that you have the necessary space, electrical capacity, and infrastructure (such as ductwork) to accommodate the chosen unit.


    5. Maintenance and Cleaning: Regular maintenance is crucial for the optimal performance of your air conditioner. Consider the ease of cleaning the filters and maintaining the unit to ensure its longevity and efficiency.
Air Conditioner Data Plate
Residential Air Conditioner Data Plate Guide

Tips for Efficiently Cooling Your Home with an Air Conditioner

  • To maximize the cooling efficiency of your home’s air conditioner and minimize energy consumption, follow these helpful tips:

    1. Proper Insulation: Ensure that your home is adequately insulated to prevent cool air from escaping and warm air from entering. Insulate windows, doors, and walls to create a more energy-efficient environment. Remember, insulation works for both hot and cold. In the winter it keeps the cold air at bay, and in the summer it keeps cool air inside your home shielded from exterior heat.


    2. Smart Thermostats: Install a programmable or smart thermostat to control and schedule your cooling settings. This allows you to adjust the temperature based on occupancy and optimize energy usage.


    3. Airflow Optimization: Keep your air conditioner’s vents and registers unobstructed to allow proper airflow. Ensure that furniture, curtains, or any other objects do not block the air pathway.


    4. Regular Maintenance: Clean or replace air filters regularly to maintain proper airflow and prevent dust buildup. Additionally, schedule professional maintenance checks to ensure that the system operates efficiently.


    5. Proper Sizing: Choose an air conditioner with the appropriate cooling capacity for the space you want to cool. An oversized unit will cycle on and off frequently, while an undersized unit may struggle to cool the area effectively.

Cost Considerations for Residential Home Air Conditioners

  • When budgeting for a residential home air conditioner, it’s essential to consider various costs beyond the initial purchase price. Here are some cost factors to keep in mind:


    1. Purchase Price: The cost of the air conditioner unit itself varies depending on the type, brand, and features. Compare prices and consider long-term savings in energy efficiency.
    2. Installation Costs: Factor in the cost of professional installation, especially for central air conditioners or ductless systems that require more extensive setup.
    3. Energy Efficiency and Operating Costs: Energy-efficient units may have a higher upfront cost but can save you money on energy bills in the long run. Consider the unit’s energy efficiency ratings and estimated annual operating costs.

    4. Maintenance and Repair Expenses: Regular maintenance and occasional repairs are part of owning an air conditioner. Budget for filter replacements, professional tune-ups, and unforeseen repair costs.
HVAC System Inspection

Common Issues with Residential Home Air Conditioners

Residential home air conditioners may encounter certain issues that can affect their performance and efficiency. Understanding these common problems can help you identify and resolve them promptly. Here are some typical issues with air conditioners:

      1. Refrigerant Leaks: Low refrigerant levels can result in inadequate cooling and reduced efficiency. Look for signs of refrigerant leaks, such as ice buildup on the evaporator coil, and have a professional technician address the issue.


      2. Frozen Coils: Poor airflow or refrigerant issues can cause the evaporator coil to freeze. This restricts the cooling process and hampers performance. Check for ice formation and ensure proper airflow to prevent coil freezing.


      3. Airflow Problems: Restricted or inadequate airflow can diminish the cooling capacity of the air conditioner. Clean or replace air filters regularly, check for blockages in vents and registers, and ensure proper sealing of ductwork.


      4. Electrical Malfunctions: Electrical issues, such as faulty wiring or capacitor problems, can cause the air conditioner to malfunction or fail to start. If you experience electrical problems, it’s crucial to seek professional assistance for repairs.

Air Conditioner Maintenance Tips

Proper maintenance is essential for ensuring the longevity and optimal performance of your residential home air conditioner. Regular upkeep and attention to key maintenance tasks can help prevent issues and maximize efficiency. Here are some important air conditioner maintenance tips to keep in mind:

1. Clean or Replace Air Filters Regularly

Air filters trap dust, dirt, and other airborne particles, preventing them from entering your home and clogging the system. Over time, filters can become dirty and restrict airflow, leading to reduced cooling efficiency. Clean or replace your air filters according to the manufacturer’s recommendations, typically every one to three months.

2. Check and Clean the Condenser Unit

The outdoor condenser unit is exposed to the elements and can accumulate debris such as leaves, dirt, and grass clippings. Regularly inspect the unit and clean any obstructions to ensure proper airflow. Use a soft brush or vacuum cleaner to gently remove debris from the fins and coils. Be cautious not to bend or damage the delicate fins.

3. Consider a Filter for the Exterior Condenser Unit

To minimize the accumulation debris an exterior filter may be worth considering. These filters a mesh-like material made to go over the condenser unit. They are often referred to as air sock filters. You have the option of buying standard sized filters, or you can get a custom made to measure filter for your exact unit. 

4. Keep the Evaporator Coil Clean

The evaporator coil, located in the indoor unit, can also collect dirt and dust over time. This buildup restricts airflow and reduces cooling efficiency. Carefully clean the coil using a soft brush or a commercial coil cleaner. Refer to the manufacturer’s instructions for guidance on proper cleaning techniques.

5. Check and Clean the Drainage System

Air conditioners produce condensation, which needs to be drained properly. Check the condensate drain line and remove any clogs or blockages. A blocked drain can cause water backup and potential damage to your air conditioner. Regularly inspect and clean the drain pan to prevent mold or bacteria growth.

6. Inspect and Tighten Electrical Connections

Ensure that all electrical connections are secure and tight. Over time, vibrations from the unit can loosen wires and connections. Before performing any maintenance tasks, turn off the power to the unit at the circuit breaker for safety. If you notice any loose connections or frayed wires, consult a professional technician for repairs.

7. Schedule Professional Maintenance Checks

While regular DIY maintenance is essential, it’s also advisable to schedule professional maintenance checks at least once a year. HVAC technicians can perform comprehensive inspections, cleanings, and tune-ups to ensure your air conditioner operates efficiently. They can also identify and address any potential issues before they escalate.

By following the maintenance tips in this residential air conditioner guide and staying proactive in caring for your air conditioner, you can enhance its performance, increase its lifespan, and maintain a comfortable and cool indoor environment.

DIY Troubleshooting Guide for Residential Home Air Conditioners

While some air conditioner issues will require professional help, here’s some common problems you may be able to troubleshoot yourself:

  1. Check Power Supply: If you’re new to home, and this is your first summer with a central AC unit then start with power. It’s not uncommon for a homeowner to flip the breaker off to AC in the winter to avoid accidental damage from running the unit. Ensure that the air conditioner is receiving power by checking the circuit breaker at the panel.


  2. Clean or Replace Air Filters: A central air system is using the same ducts as your furnace. Clean or replace the furnace filter according to the manufacturer’s instructions, or every 3 months. Clogged or dirty air filters can restrict airflow and reduce cooling efficiency.


  3. Clear Blocked Condensate Drainage: Inspect and clear any blockages in the condensate drainage system to prevent water backup and potential damage.


  4. Inspect and Clean Outdoor Unit: Check the outdoor unit for any debris, such as leaves or dirt, and clean it if necessary. Ensure that the unit has proper airflow for optimal performance.


  5. Call a Professional for Complex Issues: If troubleshooting doesn’t resolve the problem or if you encounter complex issues, it’s best to contact a qualified HVAC technician for diagnosis and repair. Signs that your air conditioner may require professional servicing include inadequate cooling, unusual noises, unpleasant odours, frequent on/off cycling, and high energy bills. If you notice any of these issues, it’s advisable to contact an HVAC professional.

ERV’s and HRV’s in Air Conditioning Systems

Energy Recovery Ventilators (ERVs) are being increasingly integrated into residential air conditioning systems due to their numerous benefits. ERVs are mechanical ventilation devices that exchange heat and moisture between the outgoing and incoming air streams. This process enhances energy efficiency while maintaining a comfortable indoor environment. 

ERV’s play a pivotal role in improving indoor air quality by removing stale air and bringing in fresh, filtered air from the outside. As air circulates through the ERV, the device captures heat and moisture from the outgoing air and transfers it to the incoming air. This heat and moisture exchange reduce the workload on the air conditioner, resulting in lower energy consumption and utility costs.

Moreover, ERVs effectively filter pollutants, allergens, and odours from the incoming air, contributing to a healthier living environment. The balanced ventilation provided by ERVs also helps maintain consistent humidity levels, reducing the chances of mold growth and other moisture-related issues.

In Calgary, it’s become a standard energy code practice for an HRV or Heat Recovery Ventilator to be included in the mechanical system on new construction.  While not exactly correct, it’s not uncommon for ERV and HRV to be used interchangeably to refer to the recovery system. Our primary concern as Calgarians is retaining heat through the cold winter, so “heat recovery” speaks to us profoundly. The major difference however between ERV’s and HRV’s is that and HRV does not recover and exchange moisture. Both systems do work to recover thermal performance regardless of whether the heating or cooling system is at play.

HRV Inspection

Residential Air Conditioning Guide Summary

Residential home air conditioners provide essential cooling and comfort during hot summer months. By understanding the benefits, types, factors to consider, tips for efficient cooling, troubleshooting common issues, cost considerations, and environmental impact, you can make informed decisions when choosing, using, and maintaining your air conditioning system. The average lifespan of a well-maintained residential air conditioner is approximately 10 to 15 years. Regular maintenance and timely repairs can extend its lifespan.

Remember to consider factors such as cooling capacity, energy efficiency, installation requirements, and maintenance needs when selecting an air conditioner. Implementing efficient cooling practices and addressing common issues promptly will ensure optimal performance and longevity of your unit. By following this residential air conditioning guide you’re well on your way to extending your units life. If you’re ever in doubt your Calgary Home Inspector is here to help!