Heating FAQ

When is the best time to replace a furnace?

There are many factors involved in determining the best time to replace a furnace such as its current operating efficiency, condition, make, model and the age of the furnace. A very basic rule-of-thumb is that every 10 years or so, efficiencies in furnace energy consumption for home heating equipment advance enough to warrant the utility savings a new furnace can bring. This is a somewhat broad generalization, many well-maintained furnaces may last much, much longer energy-efficient heating, and less quality models may only last a few years.

The only way to really know the best time to replace your furnace is to have an HVAC inspection and energy analysis performed on your heating and cooling system. We offer this service as part of any appointment, but you might get the most use of the information for free by scheduling a Comfort Advisor to perform the analysis and discuss the furnace options available to you. Every home and person is different, a Comfort Adviser can help you find solutions customized for your specific home and family’s comfort needs.

When should furnace filters be changed?

Many factors can cause air filters to become dirty at various intervals, so it depends on your location. For instance, homes near factories or airports may accumulate dust or debris more often. Furnace filters should generally be changed when there is visible dirt accumulated on the filter. Usually, a regular filter should be changed at least every season, but in many cases that is not enough. Check with your HVAC company on the appropriate time to regularly change filters in your area. Airflow is restricted by dirty filters and this can cause increasing loss of heating and air conditioning efficiency, and may even damage the HVAC equipment.

Will my new furnace work differently than my old one?

A new furnace may not operate exactly the same as an older one. When you install a new indoor comfort system in your home, you’ll probably notice it operates differently than your old system. Radical changes have taken place in the technology of the comfort industry in recent years. These changes will affect how your system operates and may also affect what you notice about your system.

Higher efficiencies in furnaces and air conditioners have become increasingly important over the past few years. Consumers, government agencies and manufacturers all see higher efficiency as a way to conserve our natural resources while reducing consumer energy costs. Today, furnaces are designed with high efficiency in mind.

To achieve higher efficiencies, new gas furnaces must move more air over the heat exchanger than older furnaces so that as much heat as possible can be sent throughout the house.

The air that comes out of your furnace registers may not seem as warm as the air was from your old furnace, but it will heat your house just as well. In fact, better airflow can improve overall comfort by reducing air temperature differences from the ceiling to the floor throughout your entire home.

Modern furnaces are designed to handle high-efficiency air conditioners and must have blowers that are efficient yet powerful enough to accommodate the add-on cooling. Since cold air is much heavier than warm air, your system needs an extra boost from the blower to get cool air throughout your home to provide you with efficient total comfort during the summer.

Higher airflow required for cooling operation could contribute to unfamiliar sound levels when your new furnace is operating because older homes’ air duct systems were designed for heating only. Service Experts offers products with multiple speed settings to allow for the varying air needs of both heating and cooling cycles.

Every time my furnace starts it makes a clicking sound, is that normal?

The clicking sound is likely the spark igniter on the furnace going through its sequence to light the furnace burners. This is normal.

My furnace has a viewport with blinking lights, what do they mean?

This port is a diagnostic tool furnace technicians use to help determine the operational status of the furnace.

What are the pipes coming out of the tip of my furnace?

The pipes are the combustion exhaust vent and outside air intake. This type of heating system is referred to as a sealed combustion system.

What is the difference between an 80% and 90% furnace?

An 80% furnace is often less expensive, is usually vented with a metal pipe, takes air from indoors for combustion, and is generally less efficient. A 90% furnace typically costs slightly more, and is vented with an exhaust and intake PVC pipes (does not take air from indoors for combustion). Most models have variable speed blower motors and are two-stage for maximum comfort.

What is the water-like trickling sound when my furnace is on?

High efficiency 90% furnaces have a by-product of water vapor. This water vapor returns to the furnace through the exhaust PVC and is then drained. The sound is normal.

What are furnace ratings?

Furnaces are rated by the Annual Fuel Utilization Efficiency (AFUE) ratio, which is the percent of heat produced for every dollar of fuel consumed.

Like the miles per gallon rating on your automobile, the higher the AFUE rating, the lower your fuel costs. All furnaces manufactured must meet at least 78 percent AFUE. If your furnace is 10 to 15 years old, it very well may fall below the current furnace minimum and waste energy.

This doesn’t mean that you should only look for a furnace with the highest AFUE rating. The efficiency rating is just one factor to consider when looking at a new furnace.

Furnaces use electricity to run fans and motors. The amount of electricity used varies greatly depending on the type of furnace. Be sure to check electricity usage prior to making a purchase decision.

There are several important factors to consider when making a purchase decision. Payback is a big factor. For instance, if you live in a colder climate, you could see payback in a few short years. But in a more moderate climate, it could take longer. In this case you may consider purchasing a mid-efficiency furnace. Remember, after the payback, you will continue to save money on your energy bills.

Other considerations are how long you plan to live in your house, special comfort needs, fuel availability and fuel cost.

All these factors, plus your lifestyle and family needs, add up to show you which furnace is best for you.

Your local Service Experts sales and service center can assist you with finding the best furnace for your home.

Can I use my chimney with my new furnace?

Furnace technology has advanced significantly in recent years, raising concerns over chimney use. As a result of changing technology, many existing masonry chimneys aren’t able to meet the specific demands of new furnaces with higher efficiency and enhanced performance.

There are several reasons why new furnaces and existing masonry chimneys aren’t compatible. The size of the chimney can be an issue. Modern, higher-efficiency furnaces transfer more heat into your home and less heat up the chimney than older, less-efficient units. While this means the consumer is getting more for their energy dollar, it also means that the existing chimney might now be too large for the new furnace. The result could be improper ventilation of flue products, which can cause condensation problems inside the chimney. Condensation in your chimney is the cause of two major problems. The water combines with flue gases and forms corrosive acids that eat away at the chimney, deteriorating tiles, bricks and mortar. Secondly, in winter, moisture freezes and thaws, breaking away mortar and bricks. Resulting damage can be extensive. A chimney can be destroyed and deterioration can create leaks into the home. Moisture can damage interior dry wall near the chimney and run back into the furnace, causing corrosion there, too.

In addition, today’s induced-draft furnaces often require an additional natural draft appliance to be installed into the same chimney for proper venting.

Other possibilities for furnace-chimney incompatibility include the absence of a tile liner in the chimney and the location of the chimney on an outside wall of the home.

The difference between an unlined masonry chimney and one lined with tile is simple but significant. An unlined masonry chimney is constructed of only bricks and mortar. A tile-lined chimney has the same bricks-and-mortar exterior appearance, but it also uses a rectangular or round-fired clay tile pipe in the center. While all new masonry chimneys are built with a clay tile liner, this doesn’t guarantee that they can be used with some new furnaces.

There are installations where it is possible to match a new furnace to an existing chimney. Certain factors such as chimney height and location, proper lining and condition of the chimney must be taken into consideration. Building codes must also be kept in mind. These requirements must be met to ensure proper draft in the chimney for adequate ventilation.

Your local Service Experts sales and service center can offer the best advice on how to configure your new furnace.