About 15-20 years for a properly maintained system, approximately 10-15 years for the compressor.

First, find a qualified contractor like a Comfort-Assured Preferred Dealer. Then check the system's SEER (Seasonal Energy Efficiency Ratio) and HSPF (Heating Seasonal Performance Factor) ratings. The higher the ratings, the more efficient the equipment and the more energy dollars you'll save.

A series of uniform test conditions resulting in a value used to approximate the total annual heating requirements divided by the total electric power used. This rating is a combination of part load and full load performance, as well as cycling losses. Thc higher the SEER, the more efficient the system in the cooling cycle.

In addition to comfort, you'll notice far greater efficiency.

Because heat pump systems move heat that is already supplied by nature, less energy is required to condition the air in your home. This results in greater efficiency, comfort and savings. Your overall efficiency, however, will vary among heat pump systems, depending on the model and manufacturer you select.

Before you purchase a heat pump system, look for the SEER/HSPF information provided. Each is a standard measure of a heat pump system's heating and cooling efficiency and is the best way to identify which system is best for your needs. The Seasonal Energy Efficiency Ratio (SEER) gives annual cooling requirements divided by the total electric power used. And the Heating Seasonal Performance Factor (HSPF) measures annual heating requirements divided by the total electric power used. Two additional means of measuring the efficiency of a heat pump system are the Coefficient of Performance (COP) and Energy Efficient Ratio (EER). During the past two decades, great improvements have been made in all of these categories.

The SEER/HSPF of the heat pump system you purchase directly affects your energy costs. The higher SEER/HSPE, the lower you can expect your heating and cooling costs to be. The lowest efficiency heat pumps manufactured today are substantially more efficient that those available only a few years ago.

Find the temperature (usually between 68 and 74 degrees) that's comfortable for you, and leave it there. It's not recommended to cut it back at night, because raising it in the morning turns on the backup heat source and wastes energy.

Keep the thermostat set at 78 degrees or higher. For each degree lower than 78 degrees, you increase your energy use 3%.

No. If you restrict air movement, you not only feel less comfort; you can also damage your compressor. Leave all doors open as well.

When temperatures are below 30 degrees in the winter and above 90 degrees in summer.

The thermostat could be set too high, need adjustment or replacing, or be exposed to drafts. It could have a low refrigerant level or be blocked by snow, ice, etc.

It may have dirty filters, too many closed registers or improperly designed ductwork. It could have a low refrigerant level, or the system may not have the capacity to cool the home.

In winter, set your thermostat and leave it there. Clean or replace filters every month. Clear snow, weeds and leaves around the outside unit to ensure good airflow. Have a Comfort-Assured Dealer perform annual maintenance checkups to make sure it's operating at peak efficiency.

It's a heat pump combined with either a fossil fuel or electric furnace. The furnace kicks in below 35 degrees when it is far more efficient. You get the best of both systems.

It has higher efficiency and lower operating costs. It provides you the security of a backup heating system. And it offers you a hedge against future rate increases.

Every summer homeowners are faced with the "repair or replace" question regarding the comfort and reliability of their cooling equipment.

Planning ahead and checking your system out early is advisable, but sometimes the hot humid conditions blanket us very quickly causing overloads on older cooling systems. Failing equipment and uncomfortable conditions force you to call in an expert to determine your options.

First, seek out a reputable contractor (or two or three) for advice, and determine the costs involved in repairing or replacing your present system. If a system is seven years old or older, most will probably encourage you to replace it in anticipation of more problems and repairs that are likely to follow.

In the long run, it can be more costly to maintain an older cooling system than to purchase a new, energy-efficient model. Take a good look at your unit's operating efficiency and compare it to what's available through the latest technical advances offered by multiple major manufacturers.

You may discover that the reduced energy bills you will enjoy with a newer model may substantially offset the costs of replacing an old system. If you would really like to replace your system but your present finances can only be stretched to cover the cost of repairs, there are many low-interest financing options available to help you buy energy-efficient systems.

Keep in mind, replacement parts won't make an older system more efficient. Repairing an older unit is sometimes a quick fix but it only puts off inevitable future repair costs, as well as the continuing loss of valuable energy dollars.

Based on age and reliability of equipment and all the associated costs involved, repair or replace? You be the judge.