How to Know You Have the Right HVAC for Your Space?
How a Professional HVAC Contractor Sizes Units
A professional HVAC contractor will size units by their BTU’s, usually at 12,000 BTUs for every 500 square feet or 46 square meters of living space. Some contractors still use tons of air per hour and not the BTU system, with one ton being the equivalent to 12,000 BTUs. This is widely used by most HVAC contractors, however, it often ends up with homeowners receiving a system which is not sized properly. More and more contractors are now turning to more effective ways to calculate loads in order to size HVAC systems more efficiently.
The ACCA has produced a Manual J, which will help contractors with their HVAC sizing. This manual the most widely used for HVAC sizing based on the needs of the homeowner in question, and not on the square footage calculations. It will take into account all the factors which often affect HVAC sizing, such as sun exposure to the temperature range in an area in question.
HVAC sizing using this manual begins with first determining the air volume needs to be based upon the square footage. Volume will be then added or subtracted from the first calculation based on insulation, climate, and air leakage. Homes in hot climates will need more cooling loads than those found in more moderate regions. Structures which are well insulated and fewer air leaks will need smaller systems than buildings which have poor insulation. Contractors need to consider also building orientation, appliance loads, shading, to mention but a few when determining HVAC sizing.
The majority of residential systems are not sized correctly, which can result in numerous issues for the homeowners. An under-sized system is unable to either heat or cool enough to keep a home comfortable, and over-sized systems will result in a home being either too hot or too cold. Which is why you need a professional HVAC contractor like Heating and Air by Jimmy Gusky to come and size your system correctly, to speak to one of our representatives in the Rockville, MD area, please call us today at (301) 298-1808.