Save with Manual J & D by Right Sizing your Air Conditioning Equipment
The Experts tell contractors the HVAC and Duct Systems should be designed to manual J & D specifications, but most don’t do it. You may not know that over sized equipment cost too much, waste energy, and can provide a lower level of comfort. The first step to avoid these problems according to the US Department of Energy Office of Energy Efficiency and Renewable Energy is to insist your contractor perform Manual J calculation, which will determine heat loss and heat gain for each room of your home under worst case conditions.
The contractor can then specify properly sized equipment that meets the Manual J calculations. Manual J heat loos and heat gain calculations considers most factors that effect HVAC equipment (glazing and window specifications, doors, insulation, lighting, appliances, climate, building size, shape, and orientation).
The International residential code requires that heating and cooling equipment be sized based on Manual J calculations. Furthermore duct systems serving heating and cooling and ventilation equipment are fabricated within the provisions within the International residential code under Manual D.
As with many code provisions, these requirements are widely ignored and rarely enforced. Most homeowners who ask contractors about Manual J or D calculations are usually met with a blank stare. Most contractors assume that if you have a 2-ton system now, then that is the replacement of what you need.
Oversizing HVAC equipment suffer from short cycling, the units don’t run long enough to achieve enough dehumidification meaning the oversized equipment brings home up to temperature quickly, and then shuts down. A few minutes later, it comes on again, only to shut off again. Building owners not only get the annoying sound of short cycling but mostly wasted energy and uncomfortable rooms.
The bottom line is that when you choose the right sized equipment you pay less and are more comfortable. If you’re looking to get a Manual J done in your building call: Eco Kong at 480-788-7718 -Your First Step Toward Comfort, Safety and Efficiency