Understanding Your Home’s Energy Consumption

Answers To Your Questions

Q: What are the best thermostat settings to maintain while I’m at home?
A:
Heating – no higher than 68 degrees; cooling – no lower than 78 degrees when you’re at home. Set heating back to 55 and air conditioning to 85 or higher when you go on vacation or when you leave home for an extended time.

Q: Should I adjust my thermostat when I go to work?
A:
Heat pumps operate best when you maintain a steady temperature. Set your air-conditioning thermostat at the highest temperature setting at which you are comfortable. Cooling costs can be reduced by about five percent for every two degrees higher you set your unit. Set your heating thermostat at the lowest setting at which you are comfortable. Each degree above 68 degrees adds about five percent to your heating bill.

Q: Should I set my thermostat for continuous fan to circulate the air?
A:
We recommend against this. Setting a thermostat to operate the fan continuously can reduce your air conditioning system’s moisture removal capability. And it may contribute to increased duct leakage infiltration, summer and winter. Also, the fan itself uses energy.

Q: Should I close off rooms we aren’t using?
A:
Shutting off rooms can actually increase your central heating and cooling system’s operating cost by causing additional air leaks. The closed-off room becomes pressurized pushing conditioned air to the outside around windows.

Q: How about closing supply air registers in rooms we aren’t using?
A:
Shutting registers pressurizes the branch duct serving that register, likely increasing duct leakage.

Q: How often should I change my filters?
A:
Once a month is best.

Q: What is the difference between an air conditioner and a heat pump?
A:
An air conditioner removes heat from your home and discharges it outside. A heat pump, during the summer, operates like an air conditioner. In the winter, it removes heat from the outside air and discharges it inside.

Q: Who makes the best heating and air conditioning equipment?
A:
The most important decision regarding purchasing new air conditioning equipment is to select an experienced, reputable contractor who has excellent references.

Q: Can ceiling fans really help cut cooling and heating costs?
A:
Yes. Try setting your thermostat to 78 degrees in the summer while running your ceiling fans. In the winter, reverse the paddle direction and run on low to bring warmer air down from ceiling. Turn the fan off when you leave the room.

Q: How much insulation should I have in my attic?
A:
R30 to R38 is ideal in most climates, including South Carolina’s. However, if you already have at least R19 insulation, the payback for adding additional insulation may be very long.

Q: Will replacement windows pay for themselves?
A:
If your windows now are single pane, installing storm windows can provide a payback in the 7-9 year range. Replacement windows may take considerably longer. You may have reasons other than saving energy for purchasing replacement window.

Q: Are tankless water heaters better than standard water heaters?
A:
Today’s water heater tanks are so well insulated that standby heat loss through the storage tank walls is minimal. An 80-gallon electric water heater provides more than enough hot water for most families.

Q: Should we turn our water heater off when we go on vacation?
A:
Since today’s water heater tanks are so well insulated, savings from turning off your water heater are very minimal. Turning the water heater off to the house may prevent damage in the event of a water leak while you are away.

Q: How about water heater insulation jackets?
A:
Insulating jackets can save if your water heater in an older poorly insulated model.

Q: Are compact fluorescents as great as people say they are?
A:
Compact fluorescent lamps can provide the same light as incandescent lamps at approximately one-quarter of the operating cost.

Q: What if my CFLs burn out too quickly?
A:
A CFL’s life may be shortened by operating in a contained fixture or turning off and on frequently.

Q: How much does it cost to run an appliance?
A:
Which appliance? We can give you a rough estimate, but the power you use will depend on your actual appliance’s efficiency and how often you operate it.

Q: If a water heater element burns out, does it cause the water heater to use more electricity?
A:
No. If lower element burns out, you will have less hot water. If upper element burns out, you probably will have NO hot water.

Q: Which is more efficient: 120 volt appliances or 240 volt appliances?
A:
Some appliances (clothes dryer, range, water heater) require 240 volt service because they require more power to operate. However, neither supply voltage has an energy-efficient advantage over the other.