GAS FURNACE AND HEAT PUMP- WHAT IS THE DIFFERENCE?

By: Patricia Cermignano

When cold weather hits, you need reliable HVAC equipment to keep your home warm. Two types of heating equipment that Bob Cermignano Air Conditioning & Heating, Inc. installs and services are gas furnaces and heat pumps. While both of these systems generate heat to keep your home warm, it is important to understand the difference between gas furnaces and heat pumps.

 

Gas Furnaces

A gas furnace is a major appliance that generates heat to help maintain comfort throughout an occupied space. The four major components of a gas furnace are:

  • Gas Control Valve- The furnace's fuel source, gas, is connected to the furnace through the gas control valve. When the thermostat initiates a call for heat, the gas valve opens, releasing gas, which then flows to the burners.
  • Burners- It is at the burners where the gas is then ignited. The flames fire from the burners through the heat exchanger, and the heat exchanger begins to warm.
  • Heat Exchanger- The heat exchanger is the component of the furnace where the heat is created. When the heat exchanger warms and heat is produced, the blower motor is activated.
  • Blower Motor- The blower motor is the component of the furnace that pushes the warm air from the heat exchanger through the ducts, circulating it throughout your home. As the air is being pushed by the blower motor to a room, the blower motor creates negative pressure through the duct's return system and draws back the air circulated within a room. The warming cycle then repeats.

 

Heat Pump

A heat pump is essentially an air conditioner that is used to provide cooling in the warmer months, but also has the ability to provide heat during the cooler months. A heat pump works in conjunction with either an air handler or a furnace in order to circulate air to your space. During the cooler months, the heat pump uses its key component, the reversing valve, to reverse the refrigerant cycle allowing the heat pump to provide heat to your home. When the cycle is reversed, the refrigerant within the heat pump will extract heat found in the outdoor air, even when temperatures outside are cooler. The heat pump compresses and transfers the heated refrigerant to the evaporator coil located inside your furnace or air handler. The evaporator coil acts as a condenser, releasing the hot air and leaving behind only cooled refrigerant. This cooled refrigerant flows back to the heat pump, where the cycle repeats. When the outdoor temperature drops below to around, or below, 30°F, there is less heat in the air for the heat pump to absorb. This is called the balance point. When the heat pump reaches the balance point, it requires a secondary heating source to help meet the home's demands for heat. The heat pump can work with a furnace to supply the necessary heat or it can work with an electric heat strip, which is added to the air handler.