Parker County Today July 2017 - Page 76

our opinions: ADVICE FROM AN EXPERT In The Comfort Zone In This Instance, Size DOES Matter W 74 hen you’re digging a hole to add a new plant to your garden, the best tool for the job is probably a shovel. You wouldn’t use a backhoe to add some petunias to your landscape. In the same vein, you wouldn’t want to put in a 10-ton air-condi- tioning unit when a two-ton unit is what your home really needs. I know we live in Texas and we like everything bigger. I know it’s hot. But one of the things we hear most when someone calls needing a new unit is that “my current unit is not cooling my house, so I need a bigger unit.” That may or may not be the case. Last month I talked about all of the different reasons your home may not be as cool as it was last summer. An improperly designed duct system, leaking ducts, loose or poorly sealed registers, or missing insulation can all make your system work harder than it should. If you’ve called a reliable company and had everything on your system checked and the result is that you need a new unit, this is the time to make sure that the unit that the company is recommending is the best one for your home. I know it’s a big investment. A new unit can cost thousands, even tens-of-thousands, depending on the size of your home. And often homeowners want a larger unit than the one that they are replacing, because the current unit is not cooling or heating the house to their desired level of comfort. It’s time to ask some questions of the installation company when they tell you what size unit they recommend. The first one is how they determined what size unit you need. Don’t be afraid, there is math involved. The contractor should have used some- thing called the “Manual J Load Calculation.” Luckily, as the homeowner you don’t have to do the math, but you should make sure that your contractor has. It is less work for the contractor to guess at the size of the equipment than it is to do a proper load calculation, according to Ron Therethy, author of This Old House Heating and Cooling. An oversized system will heat and cool, although it is not as efficient as a correctly sized one and will not last as long as its potential. It’s cheaper for the contractor to buy a bigger unit and cut corners on the installation. There’s a myth out there that a unit that runs for a longer period of time costs more than one that cycles. For example, a four-ton unit will consume twice the energy that a two-ton unit will if both run the same length of time. But when you factor the cycling effect on efficiency the four-ton will consume up to 20-percent more electricity. Electrical usage (expense) is in direct proportion to system size and efficiency, so you want to make sure that you are using the correct size system for your home. In fact, researchers at Texas A&M have determined that slightly undersized units are more efficient and better at provid- By Brett Hobson CEO Comfort Experts ing comfort.  After the correct size has been determined, ask if new duct- work will need to be installed. Make sure if they are using the current duct system that it is clean and in good repair. You don’t want to install a new system into leaky ductwork. Ask about any new technology that is on the market. There are great new tools like digital or remote-operated thermostats that can greatly improve the efficiency of your system by learn- ing when you are away from the house, or you can turn on remotely. Anything that saves a few dollars is worth looking into. Do some research and know what is out there. Make sure the system you are installing is the most efficient one possible. Ask about the unit’s SEER rating. The Seasonal Energy Efficiency Ratio (SEER) measures air conditioning and heat pump cooling efficiency, which is calculated by the cool- ing output for a typical cooling season divided by the total electric energy input during the same time frame. A higher SEER rating means greater energy efficiency