For The Right Size System Don’t Forget…“A Room-By-Room Heat Gain And Heat Loss Calculation”

Heat Loss  The amount of heating BTU (energy output of furnace) needed to replace the heat lost from a home during the cold winter months.
Heat Gain  The amount of cooling BTU (energy of air conditioner) needed to overcome the heat gain of the hot summer sun that’s entering the home.

There are six ways to size a heating and cooling system for a home . . . only one way is the right way.

1. Over the phone
2. Standing at the curb in front of the home
3. Standing at the front door looking in
4. Replacing with the same size
5. Installing the size a homeowner wants
6. Taking the time to size it right
   

A properly trained contractor will calculate the correctly sized heating and cooling system by measuring many elements of your home:

• The amount of living space
• The style or layout of the floor plan.
• The number of stories.
• The type of construction: wood, brick or block.
• The thickness of insulation in the walls, ceiling and floor.
• The number and compass direction of the doors and windows.
  

With this information he can calculate the correctly sized system using a formula supplied by Manual J (or equivalent) to meet the room by room heat gain and heat loss of your home. Ultimately, the system will be one that is not too big or too small. With the correctly sized system he’s now one step closer to guaranteeing that you will have year-round comfort without high heating and cooling bills.

4 Important Reasons To Perform A Heat Gain/Heat Loss Calculation

1. Correctly sized equipment operates more efficiently by cycling off and on properly, thus saving energy costs.
2. A heating and cooling system does not start at rated efficiency; it starts out at a lower value and works its way up its rated efficiency. A system that’s too large heats and cools the home too quickly without the rated efficiency of the equipment ever being achieved.
3. If the system is too small, it will run a lot more than needed and never heat or cool the home. This is not bad mechanically, but it does guarantee higher than normal utility cost.
4. The initial investment of properly sized system is less expensive than a larger oversized system, realizing savings right away.
   

Consumer Reports Magazine article stated:

“Beware of being sold an over-sized unit. An over-sized air conditioner will cycle on and off more
frequently, causing noticeable temperature swings and putting more wear on the equipment.”

Food For Thought . . .

For residential use, heating and air conditioning manufactures produce, on the average, eight different sized cooling systems and six different sized heating systems. They build these different sizes for your year around comfort at minimal operating costs while maximizing the life of the equipment.  If proper sizing weren’t so crucial, wouldn’t it be much easier and more profitable for them to build a “one size fits all,” or “a two sizes fits all,” or perhaps even “a three sizes fits all? “

Contact the air experts at Nevada Heating, Air Conditioning & Plumbing. Ask our tech a question, request a service or offer feedback, please.