Heating and Cooling Systems

Central Cooling

The most common central cooling system is a split system, which includes an outdoor cabinet containing a condenser coil and compressor, and an indoor evaporator coil, usually installed in conjunction with your furnace or air handler. The compressor pumps a chemical called refrigerant through the system.  Heat is transferred from air in your home to the refrigerant in the evaporator coil, thus “cooling” the air. Your cooling system is usually combined with your central heating system because they share the same ductwork for distributing conditioned air throughout your home.

Central Heating

Central heating systems have a primary heating appliance, such as a furnace, typically located in your basement or garage. All furnaces consist of four main components:

1. Burners that deliver and burn fuel
2. Heat exchangers
3. A blower
4. A flue that acts as an exhaust for gaseous by-products.

Depending on your situation, region, and needs, you can choose from heating systems running on either gas or oil as fuel, or a hybrid packaged system that can use both fuel types. Air from your home blows across the heat exchanger to be warmed. It is then blown through a system of ducts to distribute around your home. During warm seasons, your heating system works with your central air conditioning. Air is cooled as it is blown over your air conditioning unit’s cooling coil and then sent through the same air ducts through your home.

Heat Pumps

Heat pumps are designed to move heat energy from one location to another.  They typically pull heat out of the air or ground to heat a home or building, but they can be reversed to cool a building.  They transfer heat very much like air conditioning units transfer heat with refrigerant. One of the biggest advantages of a heat pump is there’s no need to install separate systems to heat and cool your home.  In moderate climates, heat pumps work very efficiently because they simply transfer heat, rather than burn fuel to create it.

System Efficiency

Heating and cooling systems are rated according to their seasonal energy efficiency ratio (SEER). SEER indicates the relative amount of energy needed to provide a specific cooling output. Many older systems have SEER ratings of 6 or less. Look for the ENERGY STAR® and EnergyGuide labels — qualified central units are about 15% more efficient than standard models.

Air Conditioning Troubleshooting Tips

• Check to make sure your thermostat is set in the “cool” position.
• Ensure that your outdoor air conditioning (condensing unit) is running:
• Check the circuit breakers in the circuit breaker box (or electrical panel), most likely mounted to an outside wall in the back of the house. Are they in the “ON” position?
• Check the outdoor unit “disconnect switch” to make sure it is in the “ON” position. The disconnect switch is located near the outdoor unit. (Typically, a grey 8″ wide x 6″ high x 4″ deep box mounted to the wall).
• Ensure that the blower motor in your air conditioner is running. (If the thermostat is in the “cool” position, the air conditioner blower should be running.) If it’s not, check to make sure the on/off switch on the air conditioner is in the “ON” position. Sometimes a switch is located at the top of basement steps.
• Be sure that you have changed your filter in the air conditioner recently. Your filter should be changed every month.
• Check all return air grilles to make sure they are not blocked by furniture.
• Check all supply air registers to make sure they are open and blowing air. (The return air grilles are normally located on your walls and are wide and flat).

Gas Furnace Troubleshooting Tips

• Check to make sure that your thermostat is set in the “heat” position.
• Make sure that the temperature setting on the thermostat is set above (or higher than) the indoor temperature showing on the thermostat.
• Ensure that there is power to the furnace: Try turning the fan to “ON” using the fan switch on the thermostat to test for power to the furnace.
• Check the circuit breakers at the electrical panel to make sure they are in the “ON” position.
• Check the SSU switch (it looks like a light switch on a gray box located at the furnace) to be sure it is in the “ON” position.
• Replace the furnace filter if needed. All 1-inch thick furnace filters should be replaced monthly.  Purolator 2-inch-thick and other high-capacity pleated filters can most likely be changed every other month; 6 times per year.
• If the system is running but you have not changed your filter, the filter may need to be replaced.
• Check all return air grilles to make sure they are not blocked by furniture.
• Check all supply air registers to make sure they are open and blowing air. (The return air grilles are normally located on your walls and are wide and flat).

Heat Pump Troubleshooting Tips

• Check thermostat settings. Is the heat pump set on the desired mode and temperature?
• Ensure the unit has power and breakers have not been flipped.
• Clean or replace the air filter in the indoor air handler.
• Ensure the outdoor unit is not blocked and has free airflow on all sides.
• Your heat pump may need a tune-up. Having your heat pump serviced regularly by a professional, qualified HVAC technician can provide higher efficiency operation and more reliable comfort. One service typically offered during routine maintenance is cleaning your outdoor coil. If the coil is extremely dirty, your system may have trouble keeping up with demand.

Call an HVAC Technician

If you’re not comfortable troubleshooting or attempts to find the issue don’t resolve the problem, it’s time to call a trained HVAC technician. Some HVAC issues are best left to the experts.  Frozen coils, water leaks in an indoor unit, an outdoor unit that will not shut off, and strange and/or loud noises are a few examples that call for a pro. Calling an HVAC technician will ensure that your repair is done safely and correctly the first time, reducing the risk of needing more costly repairs down the road.