Heating & Cooling 101

Cooling 101

Your central air conditioning system is made up of four main components including an air handler, an evaporator coil, a condensing unit, and air ducts which deliver the air to individual rooms throughout your home. All of the components of your air conditioning system need to be carefully matched together during the original installation. A mismatched system will operate poorly, and in some cases will not operate at all.

The air handler: (Typically the furnace blower is used) Blows air thru the evaporator coil and into the duct work to be circulated throughout the home. An air filter should always be located on the intake side of the furnace to clean the air before it is cooled and circulated throughout the home.

*When the furnace is used for air conditioning its blower will be energized in high speed which makes more noise and moves more air than when it operates in the heating mode.

The evaporator coil:
Sitting on top of the furnace and enclosed in an insulated sheet-metal box, the evaporator coil is connected to the outside condenser by two copper tubes, one of which is insulated with a thick rubber coating. Refrigerant (R-22 or R-410a) will circulate thru this coil to cause the cooling effect

The condenser:
The outdoor unit of a split system is the condenser. It consists of the compressor, which is a pump that circulates the refrigerant thru the evaporator coil, a large radiator type coil to transfer heat, and a fan to blow air thru the coil to keep it cool. It is important to keep the area around the condenser clear so it can operate properly.

The air ducts:
Today's ductwork consists of insulated flexible tubes that snake across the attic floor or under the house. Unfortunately, cooling ducts are out of sight and therefore out of mind and tend to be neglected when it come to cleaning and repair.
A recent study by the California energy commission concluded that the average home loses up to 30%  of the cool air before it ever gets to the rooms where it’s needed due to leaking duct work. Combined with poorly designed supply registers that don’t allow for good air circulation you could be spending up to 50% more on your cooling cost than you would with a well designed, sealed duct system, and adjustable supply vents.

Water water everywhere:
Humidity refers to the moisture that has evaporated into the air and exists as an invisible gas. As the heat is removed from air passing over the evaporator, moisture condenses out of it. We know this moisture as condensation and provide a drain line for its disposal. When the humidity is high there is more moisture in the air and more condensate will be formed. If your home construction doesn’t allow for a regular gravity flow drain to dispose of the condensate, a small water pump may be used that will pump the water to a convenient drain or outside to a small drywell dug next to your condensing unit and filled with gravel. This condensate pump contains a float switch and will cycle on and off as needed.

Size matters:
Your system needs to be properly sized for your home. The size of your central air conditioner is measured in tons of refrigeration. One ton is equal to 12,000 BTU’s/ hour of cooling capacity. A three ton system for instance would have 36,000 btu’s of cooling capacity. Too small a system will not cool your home adequately on hot days. And too large a system will cool the air in your home so fast that the humidity is not removed, leaving you  with a sometimes cold clammy feeling and in severe instances humidity condensing into water and dripping off of your air registers. Your comfort consultant will perform a heat gain analysis on your home to help you decide on the system that will best meet your needs.

All 13 SEERS are not created equal:
SEER stands for “Seasonal Energy Efficiency Ratio” and it is a number by which you can compare the efficiency ratings of different air conditioners. The minimum rating allowed today is 13 SEER and so every equipment manufacturer had to produce a 13 SEER unit. Don’t be fooled into thinking that all 13 SEER units are the same. The differences become apparent when you look closer at things like construction, quality, reliability, durability, and enhanced warranties.

Nothing lasts forever:
A good rule of thumb is that your cooling system will last about 15 to 20 years. Once it hits that age you should consider replacing it, even though it might still run and blow cold air. Installing a new high efficiency system could cut your electric bill by up to 60% when compared to the cost of running your old system. With a savings like that it simply doesn’t make sense to keep using it.

Heating 101

Single Speed / Single Stage is a basic furnace, limited in that it only provides a high heat mode. Furnaces are designed to heat your home on the coldest days. The reality is that there are only a few days per season where that condition exists. A single speed furnace does not have the ability to adjust to the milder conditions thus causing large temperature swings and a less comfortable home. In addition this condition may cause increased energy usage & system repairs.

Two-Speed / Two Stage technology enables a gas furnace to improve indoor air circulation and overall comfort, while reducing operating noise. It operates at a slower more consistent level over 90% of the time. This means lower temperature swings and cold drafts which are associated with single speed furnaces.

Variable speed furnaces feature the best technology as well as being the quietest furnaces in the industry
today. The blower motor ramps up gently, quietly and economically to provide a nearly continuous flow of warm air in a low capacity operation maximizing your comfort. The blower motor uses only one eighth of the power of a standard furnace blower motor. It also increases efficiency in your air conditioning system up to 10%.

Heat Pumps:
If you use only electricity to heat and cool your home then a heat pump is the most energy efficient system that you can use for indoor comfort. Heat pumps provide three times more heating than the equivalent amount of energy they consume. Heat pumps also do double duty as your home's air conditioner. A heat pump can decrease the amount of electricity you use for heating by as much as 30% to 40%

The Air Ducts:
Today's ductwork consists of insulated flexible tubes that snake across the attic floor or under the house. Unfortunately, heating ducts are out of sight and therefore out of mind and tend to be neglected when it comes to cleaning and repair. A recent study by the California energy commission concluded that the average home loses up to 30%  of the hot air before it ever gets to the rooms where it’s needed due to leaking duct work. Combined with poorly designed supply registers that don’t allow for good air circulation you could be spending up to 40% more on your heating cost than you would with a well designed, sealed duct system, and adjustable supply vents.

Nothing Lasts Forever:
A good rule of thumb is that your heating system will last about 15 to 20 years. Once it hits that age you should consider replacing it, even though it might still run and blow warm air. Installing a new high efficiency system could cut your gas bill by up to 60% when compared to the cost of running your old system. With a savings like that it simply doesn’t make sense to keep using it.

AFUE stands for "Annual Fuel Utilization Efficiency".
It is the way in which gas furnaces are rated for comparison. Most furnaces produced are between 80% and 96.6% efficient. Don’t be fooled into thinking that all units with the same AFUE ratings are equal. The differences become apparent when you look closer at things like construction, quality, reliability, durability, and enhanced warranties.