Have you given any thought about your HVAC system? Probably not!

In most cases your furnace sits in an area of your home, tucked away doing its job day in and day out; warming you during the winter and cooling you during the summer. It’s not until the system stops working properly that most homeowners give their furnace any consideration.

The average household spends more than $2200 a year on energy bills with nearly half going toward your heating and cooling costs. But by making a few smart decisions, you can save on those energy costs and improve the comfort in your home. If your HVAC equipment is more than 10 years old or not keeping your house comfortable, it may not be performing efficiently or perhaps needs upgrading. By replacing your old heating and cooling equipment with ENERGY STAR qualified equipment, you can cut your annual energy bill by nearly $200.

How long do furnaces last? The average furnace probably works for about 14-20 years, assuming it is properly maintained. So by the time your furnace dies and you need to buy a new one, you are looking at replacing a mechanical and electronic appliance that is almost two decades old, which is an eternity in these modern times.

So let’s say you woke up this morning and your furnace is dead. Chances are, it was designed and installed back in the early 90s or late 80s. In those days, a good furnace had an efficiency rating of about 60-80%, meaning that 80% of the gas or oil burned went to heat your house, and the rest was lost as waste heat up your chimney or vent. So you go shopping for a new furnace today, and you see 90, 92, 94, even 95% efficiency measurements on these new furnaces. What does this mean? What should you research and buy?

How A Furnace Works

As you research purchasing a new furnace, you should consider the following points:

  • Gas Furnace. For a gas furnace, which most of the United States uses, your first choice will be the heat output of the furnace, measure in British Thermal Units, or BTUs. For a 1500 square foot home, a 60,000 BTU furnace is probably adequate.
  • Measurement. Your Custom Air installer will measure your home and calculate the required size of furnace, or may simply replace the existing unit with one of the same size. If your furnace is too big for your house, it will run at full power and turn off long before it gets to an efficient heat and level, and you will be wasting money — so big is not always better.
  • The next choice will be in efficiency ratings. Most older furnaces were only 80% or less efficient. Almost all modern furnaces are a minimum of 90% on the efficiency scale, and you will see them rated all the way up to 97%. When it comes to cost, you will find about a 10% differential between a 90% furnace and a 94-95% furnace. Over the years, this additional efficiency will pay for itself so consider buying what you can afford. So the efficiency rating tells you how well the furnace turns the fuel into heat for your home — how it does that is through its burner and heat exchanger; and the blower sends the warm air through the ductwork into your house.
  • Blower. The final option is the blower, which is basically a fan that pushes all the hot air from the air handler, through the ductwork, and out through the vents in your house. Old blowers ran at a single speed. The newest blowers are variable speed, meaning they can run low, high, or anywhere in between, depending on what stage the furnace is in and how heat can most efficiently be sent into the home. These motors are very efficient and use less energy than a 100 watt light bulb, meaning you save money in gas and in electricity costs.  Compared to the old-fashion blower, the variable speed blowers run more often and at lower speeds.  This keeps the warm air circulating better in your home instead of piling up at your ceiling, away from where you are sitting. It also means your air moves through your filter more often, resulting in cleaner air.

New Furnace Installation

Installing a new furnace is not as simple as it appears. You’d think it could be done in an hour or two, but it can easily take 2 men a full 8 hour day to remove an old furnace and put in a new one, complete with venting, drainage, electrical hook up, gas hookup, etc.

Air Conditioners

Think of this – your air conditioner and refrigerator work the same way. Instead of cooling just the small space inside of a refrigerator, an air conditioner cools a whole house, or an entire business.

An air conditioner has three main parts. They are a compressor, a condenser and an evaporator. The compressor and condenser are usually located on the outside air portion of the air conditioner. The evaporator is located on the inside the house as part of a furnace. That’s the part that heats your house.

Working fluid arrives at the compressor as a cool, low-pressure gas. The compressor squeezes the fluid and packs the molecule of the fluid closer together. The closer the molecules are together, the higher its energy and its temperature.

The working fluid leaves the compressor as a hot, high pressure gas and flows into the condenser. If you looked at the air conditioner part outside a house, look for the part that has metal fins all around. The fins act just like a radiator in a car and helps the heat go away, or dissipate, more quickly.

When the working fluid leaves the condenser, its temperature is much cooler and it has changed from a gas to a liquid under high pressure. The liquid goes into the evaporator through a very tiny, narrow hole. On the other side, the liquid’s pressure drops. When it does it begins to evaporate into a gas. The evaporator also has metal fins to help in exchange the thermal energy with the surrounding air.

By the time the working fluid leaves the evaporator, it is a cool, low pressure gas. It then returns to the compressor to begin its trip all over again.

Connected to the evaporator is a fan that circulates the air inside the house to blow across the evaporator fins. Hot air is lighter than cold air, so the hot air in the room rises to the top of a room.

There is a vent there where air is sucked into the air conditioner and goes down ducts. The hot air is used to cool the gas in the evaporator. As the heat is removed from the air, the air is cooled. It is then blown into the house through other ducts usually at the floor level.

This continues over and over and over until the room reaches the temperature you want the room cooled to. The thermostat senses that the temperature has reached the right setting and turns off the air conditioner. As the room warms up, the thermostat turns the air conditioner back on until the room reaches the temperature.

Heat Pumps

Imagine that you took an air conditioner and flipped it around so that the hot coils were on the inside and the cold coils were on the outside. Then you would have a heater. Rather than burning a fuel, what it is doing is “moving heat.”

A heat pump is an air conditioner that contains a valve that lets it switch between “air conditioner” and “heater.” When the valve is switched one way, the heat pump acts like an air conditioner, and when it is switched the other way it reverses the flow of the liquid inside the heat pump and acts like a heater.

Heat pumps can be extremely efficient in their use of energy. One problem with some heat pumps is that the coils in the outside air collect ice. The heat pump has to melt this ice periodically, so it switches itself back to air conditioner mode to heat up the coils. To avoid pumping cold air into the house in air conditioner mode, the heat pump also lights up burners or electric strip heaters to heat the cold air that the air conditioner is pumping out. Once the ice is melted, the heat pump switches back to heating mode and turns off the burners.


There is no one-size-fits-all with indoor air comfort. Some people like a room extra cold, while others prefer milder temperatures. The problem is easily solved when you install a zoning system, which let you vary temperature settings throughout the house. You can divide your home into two or four zoning areas, depending on the system you purchase. You no longer need to heat or cool unoccupied rooms, or change the setting to suit the needs of one family member.

Most homes have light switches in every room, but only one thermostat for the entire house.In fact, thermostats aren’t conveniently located where most of us spend our time, like our family room.  Instead they can usually be found in a hallway or dining room.  Since this is the case, the average homeowner tends to adjust the thermostat more than 5 times per day to get the temperature “just right.”

Custom Air suggests installing a zoning system, like Honeywell’s Prestige Portable Comfort Control, to allow you to bring the thermostat to you – no matter what room you’re in.  Zoning your home allows you to control comfort in the palm of your hand.

With one zoning control, you can change the temperature in the house – anywhere in your house!And, because the Prestige Comfort System automatically manages your home’s temperature, you can cut your annual heating & cooling cost by up to 30%.

Maintenance Agreements

Just as a tune-up for your car can improve your gas mileage, a yearly tune-up of your heating and cooling system can improve efficiency and comfort.

Proper maintenance is one of the most important steps you can take to prevent future problems.  A Maintenance Program helps avoid breakdowns plus it protects and prolongs the life of your equipment.

However, it never fails heating systems have a way of breaking down when the weather is at its worst – on the coldest day of the year!  Times when your system must work the hardest and when you need it most.  As a Maintenance Service Agreement customer you always receive priority service!

Sources: www.energystar.gov