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Frequently Asked Questions

Terms used in the HVAC industry

Split System: a heat pump or central air conditioning with two components, one inside unit and one outside unit.

Package Unit: a heating & air conditioning unit that is all one unit that sits outside.

Air Handler/Fan Coil: the part of the air conditioning or heat pump that moves the air through the ducts.

Indoor Coil: the part of the air conditioning or heat pump that is located in the house and functions as a transfer point for warming or cooling the home.

Outdoor Coil/Condensing Unit: the part of the air conditioning or heat pump that is located outside that works as a heat transfer point for collecting heat from or dispelling heat to the outside air.

Supplementary Heat: auxiliary or emergency heat provided when temperatures fall below the heat pumps balance point. Supplemental heat can also be a gas or oil furnace.

Zone: an area controlled by a thermostat. Example; a two-story house with a thermostat on each floor has 2-zones, one for each floor.

Other Questions

How do I select a contractor?

Check to make sure they are licensed and insured and the technicians are trained and certified. Ask family, friends, co-workers, they are the best source of reference for finding about a company’s reputation for service and dependability. Also, check with the local Better Business Bureau.

What do SEER, HSPF, and AFUE mean?

SEER (Seasonal Energy Efficiency Ratio) is the measure of efficiency by which the cooling process of air conditioners and heat pumps are rated. The higher the SEER number the greater the efficiency, which means greater energy savings. The U.S. regulatory agencies require all new models to have a SEER rating of 14.0 or greater. Most major manufactures offer a line of air conditioners and heat pumps that range from 14.0 to 20.0 SEER.

HSPF (Heating Seasonal Performance Factor) is the efficiency measurement used to gauge the efficiency of the heating mode on heat pumps. The higher the HSPF number ,the greater the efficiency. The minimum requirement is 6.8. Most major manufactures offer a line of heat pumps that range from a 6.8 to 9.4 HSPF. CARRIER has an inverter heat pump with an HSPF of 13.0.

AFUE (Annual Fuel Utilization Efficiency) is used to measure the heating efficiency of furnaces and boilers. The U.S. Department of energy has determined that all furnaces sold in the U.S. have a minimum AFUE of 78%.

Can I just replace the outdoor unit on an older system to save money?

It is not recommended. Replacing only the outdoor unit will sacrifice you comfort and lower the efficiency of the unit. You can lose up to 15% of the unit’s efficiency by pairing a new outdoor unit with an older air handler or cooling coil. There is also the possibility that the new unit may fail sooner than normal and most of the manufactures warranties will be voided.

Should I replace or repair my equipment?

There are five questions you would need to think about when deciding about whether to replace or repair your current system.

  1. How old is your system? Is the system more than 10 years old? If so it may be wiser to invest in a new higher efficiency system. The new systems may be able to decrease your energy costs by 40%.
  2. What is the efficiency level of your current system? Replacing parts on your old system will not improve the efficiency.
  3. What is the overall condition of your system? If you have not had any serious problems with your current system it may be wiser to simply repair it. If your system breaks down often, you should consider replacing it.
  4. Are you planning to move soon? If you are going to be moving in the next couple of years it may be wise to invest in new equipment. It will improve the value of your home. If you plan on remaining in your current home it would be a wise investment to upgrade your current system to the new high efficiency equipment.

How can I reduce allergens and increase humidity in my home?

A high efficiency air cleaner can remove up to 99% of the pollen and spores in your home. There will also be a reduction in household dust, dirt, smoke, and other air pollutants. The indoor air will become cleaner and fresher while reducing allergens and other pollutants.

With a whole house humidifier you can relieve the irritating discomfort of dry indoor air. By adding humidity to the air it helps reduces static electricity, itchy skin, scratchy throats, and damage to the woodwork and furnishings. Humid air feels warmer than dry air so you don’t have to set the thermostat as high to feel the same amount of warmth which means a humidifier adds moisture to the air and improves your comfort while helping to reduce your energy cost.

If too much moisture is a problem a central dehumidifier may be the answer.

Should I be concerned about Carbon Monoxide in my home?

Yes! Carbon monoxide is a colorless, odorless, and poisonous gas that results from the incomplete combustion of fuels, such as gas (LP & natural), gasoline, kerosene, oil, wood, coal, and other fuels. Any fuel-burning appliance can be a potential source of fatal or hazardous CO levels. Fuels can produce large amounts of CO when there is insufficient oxygen available for combustion. Another hazard is when gas appliances are not vented properly or are malfunctioning.

Obvious things to look for:

  • Rust or water streaking on vent or chimney
  • Loose or missing furnace panel
  • Soot or debris falling from the chimney, fireplace, or appliances
  • Loose or disconnected appliance, vent, or chimney
  • Loose masonry on chimney

Non-Obvious things to look for:

  • Internal appliance damage or malfunctioning parts
  • Improper burner adjustments
  • Hidden blockage or damage in chimney(s)


  • Never leave a vehicle running in a garage even with garage door open.
  • Never run a generator in the house, garage, or crawlspace. Opening windows and doors and/or using a fan will not prevent the build -up of CO in the house.
  • Never burn charcoal in homes, vehicles, garages, or tents.
  • Never install or service combustion appliances if you do not have the proper knowledge, skills, or tools.
  • Never use a gas range, oven, or dryer for heat in the home.
  • Never put aluminum foil on the bottom of a gas range because it interferes with combustion.
  • Never operate an unvented gas burning appliance in a closed room or in a room where you are sleeping.

Precautionary Measures:

  • Proper installation, maintenance, and operation of fuel burning appliances are the most important factor in reducing the risk of CO poisoning.
  • Make sure the appliance(s) are installed according to manufacturer’s instructions and local codes.
  • Always follow the manufacturer’s direction for safe operation.
  • Have the heating system inspected and serviced yearly by a trained, certified service technician.
  • Examine vents and chimneys on a regular basis.

Symptoms of CO poisoning can mimic illnesses such as influenza or the common cold. Some common symptoms are headache, fatigue, shortness of breath, dizziness, and nausea.

It is highly recommended that you install CO detectors.

How will the new environment friendly refrigerant affect me?

"The Clean Air Act of 1990 prohibits the production of HCFC-based air conditioners and heat pumps by 2010, and bans Freon®-22* production by 2020. As Freon® production reduces; its cost is predicted to increase."