Whether you are adding central air conditioning to an older home for the first time or you have finally accepted that your current system could benefit from an upgrade, there are a few essential considerations to make while you select your next system. While you should always consult with a qualified HVAC technician before purchasing a unit, there are two basic steps to determining the best size unit for your residence.
How Many BTUs Are Necessary for Your Space?
Manual J Calculation
You should inquire with your utility provider before you contact your HVAC technician. Many companies will conduct a free energy audit when you ask for your Manual J calculation.
Use Square Footage Measurements
If precision isn’t important to you, you can make estimates on your home’s BTU requirements based on the square footage of your residence. A 2,000-2,500 square foot home will require approximately 34,000 BTUs, while a smaller household of roughly 1,000 square feet will require approximately 18,000 BTUs.
Choosing the right size HVAC unit is crucial to the efficiency of your unit. If you’re already upgrading a unit due to inefficiency and high utility bills, choosing the wrong size unit may not do much to reduce your utility bills or improve efficiency. Units that are too large for your house size will result in frequent cycling between on and off, which will raise your utility bills, whereas units that are too small won’t be able to keep up with the cooling demands of the space and won’t turn off frequently enough. Once you have requested your Manual J calculation or estimated the required BTUs for your household size, you can begin shopping for a unit.
Be Discerning About Your HVAC Unit Selection
Work with your HVAC technician to select the best manufacturer and model for your square footage. In some cases, you won’t be able to find the exact unit size you need. If your Manual J calculation suggests a 25,000 BTU unit, you may only be able to find a 20,000 BTU or 30,000 BTU. In this case, it’s always worth it to size up, but not too much. Having a heavier-duty HVAC unit will give you the confidence you need to trust that your unit will be able to handle hot and cold weather extremes.