We’ve been in this business for a long time and are fairly confident we know the answers to your air conditioning questions. Whether you’re a new homeowner or someone dealing with an aging AC unit, you’re bound to have questions when it comes to service, maintenance, and repairs. This comprehensive FAQ guide answers the most common concerns (and a few you may not have thought to ask!) to help you learn the basics of maintaining an AC system.
Below, you’ll also find an infographic that contains the answers to some of the most common questions we run into in this business.
If you aren’t sure which one you have, then think about whether the cool air comes from vents or directly from a unit. A ductless air conditioner, often called a mini-split system, is a small-unit alternative to traditional central air. It consists of two main components: an indoor air-handling unit and an outdoor compressor. The absence of ductwork makes these systems ideal for older homes, room additions, or spaces where extending ducts isn’t practical.
Central AC might be connected to your furnace and offers cooling from one main appliance (which also has an outdoor component) to the rest of the home.
Every household is different and it depends on the filtration system you have. One-inch (1”) throw-away filters are typically replaced four times yearly. This can, however, vary based on factors such as pets, allergies, high traffic, and how often the system runs. If you have a media filter (4” or 5” wide), this is typically replaced once every 6 months or once every year. Again, depending on your situation. Regular filter changes also help your system operate more efficiently, preventing unnecessary strain and the associated costly repairs down the line.
With proper care and maintenance, an air conditioning unit can last up to 10–15 years. Regular inspections, cleaning, and professional tune-ups are essential for extending the lifespan of your AC. Ignoring maintenance may lead to early breakdowns and costly replacements, so it’s wise to stay on top of upkeep.
SEER stands for Seasonal Energy Efficiency Ratio. It measures the energy efficiency of your air conditioner over a typical cooling season. SEER2 is an upgraded set of standards built upon the original SEER ratings. It is now required for new equipment.
A higher SEER or SEER2 rating means the unit uses less energy to cool your home, which translates to lower utility bills. For example, upgrading from a SEER 10 to a SEER 18 system can significantly reduce energy costs over the life of the unit.
You can find a conversion chart for the efficiency ratings here.
There are a few clear signs your AC may need attention:
If any of these symptoms occur, it’s best to schedule a professional inspection before a minor issue becomes a major repair.
If your AC’s drip pan is damaged or rusted through, it may seem like a simple fix, but this job is best left to professionals. The drip pan is often located in difficult-to-reach places and removing it improperly can cause water damage or disrupt the condensate drainage system. A trained HVAC technician can ensure the job is done safely and that any underlying causes of rust, such as clogged drains or poor ventilation, are also addressed.
Installation of a central air conditioning unit typically takes 6-8 hours. Under ideal conditions—i.e. with easy access and no unexpected complications— it can be completed in a single day. However, older homes, electrical issues, duct modifications, or adding a new thermostat can extend the timeline. Your HVAC contractor should provide a realistic schedule after inspecting your home and discussing your needs.
The AC unit is made to withstand winter conditions. If you choose to cover your AC, ensure to use a cover that is made for your specific AC unit, as it is important to allow the unit to breathe. That is, you want to avoid fully wrapping the unit in plastic or airtight materials, as this can trap condensation and lead to corrosion or mildew inside the system. You could also choose to cover the top only to prevent icicle damage. If the icicles are large enough, they can actually damage the motor or the motor’s fan blades.
So, in short, partially covering the outdoor AC unit during off-seasons is a smart idea when done right.
In addition to annual inspections, there are a few things homeowners can do between professional service calls:
Staying proactive with these simple maintenance tasks can enhance system performance and reduce the need for emergency repairs.
An AC unit that freezes up could be dealing with several underlying issues, including:
Low refrigerant levels can only be added to a system once the leak has been found and repaired. The laws of refrigerants prevent us from “topping up the system”, meaning adding refrigerant to the system without finding or repairing the leak. Sometimes, the leak can be detected and repaired quickly. Periodically, it could take hours to determine where the refrigerant leak is coming from.
If your unit develops frost or ice, turn it off immediately and allow it to thaw. Then, call a technician to diagnose the root cause before running it again.
Depending on the age of your air conditioning system, and if you have a refrigerant leak in the indoor evaporator coil or the outdoor condenser coil, this can be an expensive repair. It may be wiser to replace your aging AC system. Condenser fan motors can be very expensive, particularly with the tariffs.
A good rule is the “$5,000 rule”: multiply the cost of repair by the age of the unit. If it exceeds $5,000, replacement is usually more cost-effective. Also, consider the frequency of breakdowns, energy efficiency, and whether your current system can meet your home’s cooling needs. Newer units with high SEER2 ratings may reduce long-term costs significantly.
A typical AC servicing appointment includes:
Regular service keeps your system reliable and efficient — and may even be required to maintain your manufacturer’s warranty.
For this area of Ontario, the design outdoor temperature is based on approximately 90 F or 32 C. The recommended indoor temperature should be set for approximately 74F or 23C at the thermostat. Having said that, a properly sized air conditioner should be able to maintain a temperature difference of approximately 16F or 8C “swing”.
Therefore, assuming filters are clean, the unit is sized correctly for your home, the thermostat is set at the correct temperature, refrigerant levels are good, the outdoor unit is clean, the furnace fan is blowing the correct amount of air and the drain is getting rid of the humidity, the air conditioner should work well.
There are times when the outdoor temperatures soar above these design temperatures. As long as the air conditioner is giving an approximate 16F or 8C “swing” in the home and the humidity is being removed, then the air conditioner is running fine.
If you’re unsure about your AC system or have concerns, don’t hesitate to contact a licensed HVAC technician at Appleby Systems. Regular maintenance and timely service are key to comfort, energy savings, and peace of mind.
Contact us today to book a visit or learn more about our services.
