(This comprehensive section on energy conservation and efficiency is provided as a service of our Heating and Air Expert, J.E. Shekell)
Residential – energy conservation check list
Do you know that up to 25% of your heat can go out the window?
Air leakage can be a major problem in both new and existing homes. Eliminating air leakage can save you money and make your home more comfortable and easier to heat and cool.
Air leakage (not only in structure of the home but air leakage in duct work) can:
Note: Recommended measures to address air leakage problems in the home air seal attic area (by-passes and tops of walls)
Important notes below before you insulate!!!!
The areas of your home that need insulation are typically attic, exterior walls, basements, crawl space, ceilings and overhangs. These entire parts make up what is called the "thermal envelope". This thermal envelope is like a blanket. It separates the inside conditioned area from the outside conditioned area. Recommended insulation levels:
Note: Increasing attic insulation to recommended R-value can save up to 30% of your heating/cooling costs. Improving exterior wall insulation can save up to 20% of your heating/cooling bill.
Check air filters. They need to be replaced or cleaned more often during peak weather conditions because your heating/air conditioning equipment runs longer. Restricted air filters will block air flow and cause your equipment to work harder and less efficiently. Choose air filters that do not restrict air - flow. Some washable and electrostatic air filters reduce air flow as much as 40%.
Restricted air - flow is as bad or worse than a dirty filter or closing your registers off. Keep supply and return registers free of clutter and open for maximum flow. In most cases, floor register deflectors are not an advantage.
Check any attic or crawl space mounted duct system for loose or leaky connections or joints. Duct work should be sealed and insulated if installed in an unconditioned space. Typical duct systems lose 25% to 40% of the heating or cooling energy put out by the central furnace or air handler.
A properly sized, installed and balanced duct system is the most important item in any heating/air conditioning system. It can be 90% of how effective, comfortable and efficient the total system is.
Note: The cracks and leaks in ductwork typically have an area that is 10% to 20% of the leakage area of the house. Over the course of a heating or cooling season, the energy losses from ducts when the fan is off can be nearly as great as when the fan is on!!!!
Extensive studies of new and existing homes in Evansville and throughout the country have found that improperly installed or sized, poorly sealed, and un-insulated ductwork is often the most prevalent energy waster.
Leaky duct - work is also a major health hazard. Kinked or collapsed ducts will cause restriction of air - flow. Duct systems lose energy in two ways: By conduction of heat from the warm surface, and air leakage through small cracks and seams.
Homes with forced air heating/cooling systems use duct systems to distribute the air through the house. The duct system is made up of a supply system and a return system. The supply system distributes the heated or cooled air throughout your living space. The returns bring the heated or cooled air back to the furnace or air handler to be reheated or re-cooled.
Leaks in your duct system can vary from small to catastrophic. Small leaks are usually in the seams and joints. These small leaks can add up to a very large leak and can significantly contribute to higher energy consumption/cost. Catastrophic leaks include disconnected ducts, or large holes in the duct system.
All leaks (even small ones) should be sealed. Look for holes large enough to see. Visible holes in ductwork would be a clear indication that the system needs fixing. The joints between duct sections should be sealed against leakage. If duct tape was used for this purpose, it often loses adhesiveness after a few years.
Duct sealing should be done using a silicon caulking or a special cement (mastic) with an imbedded fabric. If the ducts are in the attic or crawl space that is nearly as cold or warm as the outdoors, the heating or cooling is nearly completely lost if it is not insulated or sealed properly.
Adjust your thermostat temperature. During winter, for every degree you lower your heat (within the range of 60 deg. To 72 deg.) you save about 3% of your heating consumption. Wear a sweater – a light long sleeved sweater makes the room feel 2 deg’s. warmer, a heavy sweater makes it feel about four deg’s warmer, and two light sweaters make it feel five deg’s warmer.
During summer, for every degree you raise your air conditioner thermostat setting (within the range of 70 deg. To 80 deg.) you cut cooling consumption 3% to 4%. Wear lightweight clothing in the summer.
Thermostat location should be on an inside wall away from windows and doors and be sure to seal the hole behind the thermostat. Do not locate thermostat in the kitchen or on the wall of a utility room which contains furnace, water heater, washer and dryer. Don't place lamps, TV sets or other heat producing devices beneath a wall mounted thermostat. The heat source from these areas will cause the thermostat to work improperly causing erratic operation of your heating and cooling equipment. This will put unnecessary wear and tear and cause the system to be inefficient.
Programmable or setback thermostats can be a big energy saver for homes, if used properly. They automatically adjust the temperature setting when people are sleeping or are not at home. Be certain that the programmable thermostat selected is designed for the particular heating and cooling system
Note: Improper thermostat, programming or use can actually increase energy bills. Keep the temperature setting on the water heater no higher than 120 deg. Insulate the water heater especially if it is in an unconditioned space such as a garage. These are simple to install and are inexpensive. This will save energy, reduce the risk of injury from scalding, and provide plenty of hot water.
Repair leaks promptly. Do not allow faucets to run continuously while rinsing dishes, shaving, or washing hands. Check direction of ceiling fans for proper and efficient operation.
In winter the fan should be running counter clockwise on slow speed to gently push heated air down from the ceiling especially with high or cathedral ceilings. (if you stand under the fan and can feel the air blow on you it is correct). Remember heat rises. In summer the fan should be running clock wise on high speed to draw the cool air up. (if you stand under the fan and it doesn't feel like you feel air movement it is correct). You will notice that curtains and ribbons will draw away from the wall. Remember cold air is heavy and falls. This will pull it up off the floor to your comfort level. This will also help second floor rooms feel more comfortable.
Inspect your furnace’s combustion area and vent system before each heating season. If you find dirt, soot or rust, your system may not operate properly or at its peak efficiency. Call your servicing dealer and do not operate your furnace until it is professionally inspected. Have your heating and air conditioning system inspected and cleaned at least once a year to be sure your system is running safely and gives you the best performance at the lowest cost. You may also want to ask about an economical service contract that covers seasonal inspections for a flat fee. (equipment tune up) These preventive maintenance inspections not only maximize efficiency, comfort and helps extend the life of the equipment, but more importantly health and safety.
Improper venting of gas appliances is a major source of carbon monoxide poisoning. Inspection of heat exchangers is important, not only for blockage and cracks that can introduce carbon monoxide into the home but it can cause fires due to flame rollouts. This would also be for safety reasons by checking for proper operation, combustion and ventilation, heat exchanger condition and cleanliness, safety switches, fan operation, proper gas pressure, electrical connections, clean coils, blowers, thermostat operation, inspect flue pipes, draft diverter, check valves and adjust pilots.
Invest in a humidifier to conserve energy in wintertime. The air in your home won't be as dry, so you stay more comfortable at a lower temperature setting, and it’s good for your health, furnishings, and helps reduce shrinkage or doors and windows thus further eliminating air leakage and infiltration.
Keep your outdoor unit clear of debris, leaves, and shrubbery for free flow of air through the unit. Replacement of your old, inefficient gas furnace is another way to reduce your heating cost.
There is no one best furnace model for all homes, because each house and each family’s lifestyle is different. Choosing the correct unit for your can cut your heating bills up to 40%, (depending on the age of your equipment) and dramatically improve, your comfort. The savings can pay back the cost of the upgrade several times over its life.
Furnaces offer a range of capacities and efficiencies. There are additional features and benefits available. The most important step to select a furnace is to ensure that the unit’s specifications fit your need. Also, that it is bought from a contractor who installs it properly, and that it’s adequately maintained. A furnace's life expectancy is 18 to 20 years.
The most common reason for service calls for furnaces is human error. Inadequate maintenance, for example, or improper installation, inadequate duct - work, and inferior equipment.
How large a furnace? When it comes to furnaces, size counts - a furnace that is too small won't keep the house comfortable during extreme cold. Partly to avoid that possibility, some contractors sometimes sell furnaces that are too large for the home they're installed in.
Cost is only one problem with such a unit. Compared with a correctly sized furnace, a furnace that is too large will cycle on and off more frequently. That puts more wear on its components, wastes energy, and cause the temperature to vary uncomfortably. You may need to consider your home’s vents and chimney when you are purchasing a new furnace.
Replacing a low efficiency furnace with one that has an AFUE of 90% or more will require installing a vent that meets the special needs of a high efficiency furnace. Furthermore, if other appliances( gas fired water heaters) share a vent or chimney with the old furnace, they, too, may need new or modified venting.