At AirZone HVAC Services, we tend to receive the same questions every season during heat waves concerning the operation of central air conditioning units. As an industry leading source of HVAC information our goal is to ensure all our clients understand how their systems work and what to expect throughout the cooling season.
Below is the most frequently asked questions we receive:
How quickly should my AC cool the house?
This is a very common question and we receive and is dependent on many different factors:
1)What is the outdoor temperature?
2)What was the starting indoor temperature?
3)What is the humidity level in the home?
4)How well designed and installed is your ductwork?
5)How well is your home insulated?
6)Do you have a lot of windows? Are the shades closed?
All of these things will affect your cooling rate.
The reality is that HVAC designers utilize a formula to size your air conditioner. We use load calculations that take into effect the “average design temperature” to ensure we are installing the right sized unit at your home. We design air conditioners in Ottawa to approximately 29 degrees Celsius. This is because 96% of days during the year are 29 degrees or lower. If we sized our units for higher than this, much of the year the unit would short cycle (turn on and off) and make your house feel cold and clammy with drastic temperature swings.
With this in mind, on the extreme days where we have long periods of 30 degree temperatures and higher, your air conditioner will run for very long times in order to maintain your desired temperature.
Summary and Tips
Your air conditioner should be able to *maintain* your desired temperature on hot days. If you allow your home to get very hot and humid, it may take the unit all day and into the evening to catch up to your desired temperature. Your unit will need to remove the humidity in the home, over time, in order to make the house feel comfortable. We also recommend ensuring you do not allow your home to get too hot before turning on the air conditioner. When the temperature reaches extremes close to 40 degrees even an oversized air conditioner will struggle to get your home to 20 degrees as the system is simply not designed to do so.
High end multi stage units are a great way to ensure your home can keep up on even the hottest days while also ensuring you are removing humidity and keeping the house comfortable on cooler summer days. Call our office to discuss these options!
Why is my top floor so hot?
Many people experience this issue, a discrepancy between the temperature in the basement, main floor and top floor. This is easily explained, as most homes have one thermostat that is reading the temperature from the main floor. As cold air settles and hot air rises, the top floor is inevitably warmer than the rest of the house.
Summary and Tips
To battle this problem you can do a few things:
1)Balance your ductwork: closing vents and dampers in the basement and ensuring the top floor vents are open can help push more cold air to the bedrooms. **do not close off all vents in the basement and main floor as this can cause the system to freeze due to lack of airflow. Call the office if you would like a professional balancing.
2)Ensure filter is clean: Your furnace filter can become congested and blocked making the system struggle to distribute air
3)Ensure your vents are clear in including the return side
4)Make sure the furnace fan is constantly running and you leave your thermostat set at a constant comfortable temperature
5)Ecobee thermostat! An ecobee thermostat has a remote sensor that you can place on the second floor. You can then balance the temperature between the first and second floor or even override the main thermostat to read from upstairs!
6)Zoning. The experts at AirZone can help you zone your system. This allows you to run separate ductwork to the second floor and control it with an independent thermostat than ensures your home is perfectly comfortable.
Why is my air conditioner not keeping up?
Again, in the Ottawa area there are many variables as to why your unit is not keeping up:
1)The unit is old and inefficient
2)You have poor distribution through your ductwork
3)You may be running an HRV that is bringing in hot, moist air into the home
4)Your insulation is poor and allowing hot air into the home
5)You allowed your home to get to hot and humid prior to turning on the air conditioner
Summary and Tips
To battle this problem you can do a few things:
1)Maintain a comfortable temperature all year, never allow the home to get very hot and humid
2)Ensure your HRV is not running in a exchange mode in the summer, recirculation is fine but bringing in hot humid air all summer can hinder performance of your HVAC system. We can help with ERV’s that are designed to run in the summer and winter! Call our office to discuss improving the air quality of the home as well as the AC performance
3)Seal your ductwork. We can aid in ductwork sealing, but a homeowner can also seal all cracks and leaks that are accessible with tin tape!
4)Make sure the filter is clean and the outdoor unit is clean and free of debris.
5)Schedule a routine maintenance/cleaning
Should my unit run all day?
Your HVAC system is designed to run for long periods of time, especially on very hot days. Long run cycles ensure proper dehumidification and can aid in nice even temperatures throughout the home. You should be concerned if the unit is running all day and not changing the temperature in the home. A perfectly sized unit will turn on and off even on the hottest days, it just may do so less frequently.
Summary and Tips
To battle this problem you can do a few things:
1)Maintain a comfortable temperature all year, never allow the home to get very hot and humid
2)Ensure your HRV is not running in a exchange mode in the summer, recirculation is fine but bringing in hot humid air all summer can hinder performance of your HVAC system. We can help with ERV’s that are designed to run in the summer and winter! Call our office to discuss improving the air quality of the home as well as the AC performance
3)Seal your ductwork. We can aid in ductwork sealing, but a homeowner can also seal all cracks and leaks that are accessible with tin tape!
4)Make sure the filter is clean and the outdoor unit is clean and free of debris.
5)Schedule a routine maintenance/cleaning.
If all of these fail and your unit is over 12 years old it may be time to consider a new AC unit from AirZone HVAC Services. If you would like an evaluation or maintenance of your unit we would be pleased to help you out!
