By Pat Keegan and Brad Thiessen
Q: We moved into our home last spring. It’s pretty new and seems well-insulated in winter. But it was hot last summer, so we had to run the A/C a lot, and the electric bills were a killer. Do you have any tips on how we can cool our home this summer—without going broke?
A: We’ve discussed some of the easiest ways to make your home more efficient, like reducing solar gains, insulating and ventilating the attic, and sealing air leaks. You may need to focus on inefficiencies in your home’s cooling system. But before we address that, let’s look at some other potential problems:
- Do you have freezer or second refrigerator in the garage? This can be a major energy hog, especially if it’s old and you live in a warmer climate.
- Do you have a well? Your pump may be draining your energy use as you rely on it more during the summer. Start by looking for leaks in the system, and if necessary, reduce irrigation.
- How about a swimming pool? It may be time to overhaul or replace the pool pump. If the pump is in good shape, try putting it on a timer.
If you have central air conditioning (A/C) or a heat pump, make sure your filter has been changed or recently cleaned. The next step is to call an HVAC contractor for a tune-up and a complete assessment of the system. A tune-up can improve the efficiency and extend the life of the unit. The tune-up includes cleaning the condenser coil, a check of the refrigerant levels and a good look at the pump and electrical contacts. Talk to the contractor about the efficiency of the A/C unit. If it’s old, it may be cost-effective to replace it, even if it’s still functional.
Ductwork is equally important as the A/C unit, so make sure the contractor you choose is capable and willing to provide an expert assessment. A real pro will know how to measure the air flow at each supply and return register. If you’re not getting cool air to the rooms that need it, the contractor may be able to make modifications to the ductwork.
Leaky ductwork could be your problem. If the ducts are in unconditioned areas like a crawl space or attic, it’s especially important to make sure they’re sealed and insulated. It will also help to seal ducts that are in conditioned spaces.
Some HVAC contractors can do a duct-blaster test to measure duct leakage. Discuss whether you should ever close any supply registers. Most experts recommend that supply registers are always open.
If you cool your home with window A/C units, there are a few things you can do to maximize your cooling while keeping costs as low as possible.
Use window A/C units in rooms that can be closed off with a door, to make the cooling as effective as possible.
Make sure you have the right sized unit for the size of the room. A unit that’s too big will cool the room before the humidity has been lowered, which will make it feel less cool, while a unit that’s too small will have to work harder, causing a shorter life span—and it may not do the job.
Use an electric fan or ceiling fan to help distribute the cold air throughout the area you are cooling.
Turn off the A/C unit when no one is in the room.
If your window A/C unit isn’t cooling properly, it may need to be replaced. Look for an ENERGY STAR-certified unit to make the most of your cooling dollars.
Of course, the simplest way to save money on your A/C is to not use it. As much as possible, keep your activities limited to rooms that are easily cooled. Try to spend more time cooking and eating outside. If you have a basement, think about setting up a second bedroom down there where it’s cooler. Think of it as your new summer hideaway!
This column was co-written by Pat Keegan and Brad Thiessen of Collaborative Efficiency.
For more information on getting the most from your A/C, please visit: collaborativeefficiency.com/energytips.