Not necessarily! It’s certainly true for example, that an oversized furnace will heat up your house quicker than a smaller one but it can cause greater temperature swings in the home too…and that can cause a problem. Here in Tidewater, Virginia…most of the time (about 80%), even the capacity of a properly sized heating system, is far greater than that which must be available when design temperatures are experienced.

     In our area, code requirements state, that a properly sized heating system should keep the inside temperature at 70° when the outside temperature is +15°…that’s what’s known in the trade as a 55° temperature difference (TD). That means that on a day when the temperature drops to +15° outside, your heating system (provided everything else like clean filters etc, are OK) will still maintain a 70° inside temperature.

     But, how many days in a winter does the temperature actually get that low? You can almost count them on one hand. And even when it does, how long does it stay that low?...and it’s mostly at night when everyone is (or should be) in bed.
         
     So what happens to this excess capacity when the temperature is not +15°? Well, that’s the function of the thermostat…to turn the heating system “on” when the temperature falls below the thermostat setting (and to turn it “off”, when the desired temperature is reached).  
         
     Unfortunately (?), heat can’t be turned “off and on” like a water faucet and unlike what many people think, when a heating system comes “on”, unless it otherwise equipped (we’ll discuss that later), it always produces it’s full capacity. It can’t provide just a “little bit” of heat.

     Standard heating systems are limited to providing “full-on heating”, followed by “full-off cycles” and once started, it takes up to 10 minutes before your system is operating at peak efficiency and performance and about the same length of time to be safe to shut down after the thermostat is satisfied.
         
     This results in up and down temperature swings, hot and cold areas in your home and periods of discomfort…and this happens with a properly sized heating system. When the system is oversized, you can easily see why “Bigger is NOT Better”.       
         
     The same holds true with cooling systems…only worse. While heating systems in our area are designed for a 55° TD, cooling systems are only required to provide a 15° TD (75° inside; 90° outside). Because we know that unlike the winter when design temperatures are rarely reached, 90° days in the summer can be quite common in our area and that’s when cooling is needed most. So Climatemakers designs the cooling systems it installs for a 20° TD, for we know that (1) many days exceed 90° and (2) unlike heating systems, when design temperature conditions are reached, it’s just when you need cooling the most!
         
     But what happens when you don’t need that excess capacity? The same thing that happened in the heating example above. An oversized air conditioner will cool your house quicker…too quickly, in fact. The result…a cold clammy feeling when the temperature is quickly lowered without adequately removing sufficient humidity…and because removing moisture (humidity) requires long run times (so enough moisture laden air can flow over the cold coil and condense), an oversized system shuts off before proper dehumidification can occur. Definitely “Bigger is not Better”!

     Today’s homes are larger, better constructed with more insulation and storm windows…but they present more heating and cooling challenges than ever before. For example, an airtight home may be good from a savings perspective, but it's not good from an indoor air quality perspective. Fortunately, many of these comfort issues can be solved by a few modifications in your home's indoor climate system!

     We encourage you to take the time to think seriously about your heating (or cooling) system, especially if your system needs service or you are considering a replacement. It’s going to have a considerable effect on the indoor environment in your home…the indoor climate…which can directly affect you and your family’s health and comfort for a long, long time. Good overall economics and an extended, reliable, system life are also other factors that will be decisive when making your choice.     
         
     We’re experts in the installation and maintenance of residential cooling and heating systems to achieve optimum indoor air quality and energy conservation. We're also one of the oldest, locally owned, family-owned, HVAC businesses in the area.

     Our experienced sales or service representative will not just take for granted that the size of your existing unit is the correct one (or do like so many contractors, automatically recommend the next larger size) but will measure your home and calculate the actual heating & cooling load of the home.

     Our calculations incorporate window size and direction, walls, ceiling, floor, appliances, insulation, and much more. We'll compare this to your current equipment, and make any necessary adjustments for your lifestyle that are required.
         
     In our next newsletter we’ll discuss several other reasons why “bigger is not necessarily better”.