Heating Systems and Services F.E. Moran

Heating

Central Heating

Application:
Central heating is used in applications that utilize a duct system. The furnace heat is distributed throughout the building via ducts. Central heat is the most used form of heat in the commercial, retail, and food service industries (epa.gov). Approximately 86.7% of the occupied homes in the United States are heated via central heating (census.gov).

Operation:
Central heating takes place in a central point, such as a furnace or mechanical room, and then the heat is distributed throughout the building through ductwork. The heat source is created through the ignition of natural gas, propane, or fossil fuel or it can run on electricity.

Special Considerations:
Central heating can have fluctuations in temperature throughout a room; there is no option for zone temperature control; and central heating can carry allergens through the ducts if the ducts or furnace are not properly maintained.

Boiler

Application:
A boiler, furnace, or heat pump can be used in any application. However, there are a few differences. Boilers use hot water distributed throughout the building in pipes to provide heat. This has the advantage of zone controls. Each room can control its own heat. Another benefit is, without ducts, allergens cannot be distributed throughout a facility. These benefits make boilers the best choice for facilities 5,000 square feet or larger. According to eia.gov, boilers are the most popular form of heat for educational and large commercial buildings.

However, because there are no ducts for heat, ducts will need to be installed for air conditioning. Boilers come in various sizes to accommodate different facility types and sizes. There are several different types of boilers to choose from based on each individual application:

  • Fire Tube Boiler
  • Water Tube Boiler
  • Packaged Boiler
  • Fluidized Bed Combustion (FBC) Boiler
  • Atmospheric Fluidized Bed Combustion (AFBD) Boiler
  • Stoker Fired Boilers
  • Spreader Stoker
  • Chain-grate Stoker
  • Traveling-grate Stoker
  • Pulverized Fuel Boiler
  • Waste Heat Boiler
  • Thermic Fluid Heater

Operation:
A boiler is a sealed, usually steel, vessel that contains the combustion of one of several types of fuel including wood, coal, oil, or natural gas. The fuel heats water, which is then sent through pipes to radiators or to a fan coil unit that will heat air.

Special Considerations:
A boiler will need to be bled of excess air periodically. A dehumidifier may be needed to counteract the possibility of a higher humidity derived from the boiler.

Furnace

Applications:
Furnaces can be used to heat most facilities. They are the most popular form of heat for residential and smaller commercial buildings (1,001 - 5000sf) due to the low cost and dual-use ducts for central air conditioning. According to eia.gov, furnaces are most popular in office buildings, retail, service, and food service buildings.

Operation:
When the temperature in the facility falls below a predetermined level, gas flows into the electronic ignition system. The combusted gas rises past the heat exchanger and through a vent leading outdoors. A motor then pulls air into the furnace from an exchange. This air passes the combusted gas, heating the air. From there, the heated air is distributed throughout the building through the ductwork.

Special Considerations:
Furnaces have some maintenance that must be done in order to keep them working efficiently. Without regular maintenance, a furnace can cause numerous problems. Ductwork could leak in the seams, reducing heat efficiency. If filters aren't replaced, allergens can be distributed throughout the building through the ductwork. Dirty burners cause gas not to burn thoroughly. If gas does not burn completely, it will result in less heat and higher gas bills.

Heat pump

Application:
Heat pumps are an efficient form of both heat and air conditioning for small buildings. They are the most popular form of heat in healthcare facilities. Heat pumps are a good choice for those who want an energy efficient system. They distribute heat evenly and are quiet.

Operation:

Step 1: A coolant cycles through the heat pump system and collects the surrounding heat. The absorption of the heat causes the coolant to turn into a gas.
Step 2: The compressor condenses the coolant. Now that the coolant is a gas, the condensing process increases the temperature of the gas.
Step 3: The heated coolant now moves through the water in the radiator. While the gaseous coolant is circulating, it is radiating its heat into the environment. Through this process, it loses its heat and becomes a liquid once again.
Step 4: The coolant runs through the expansion valve and begins the process again.

Special Considerations:
Heat pumps are best for climates that remain above 30 degrees. Below 30 degrees, the ambient outdoor heat is no longer abundant enough to pump into the home once the temperature reaches below 30 degrees. A backup heating system may be needed for climates that reach freezing temperatures. Heat pumps must have regularly scheduled maintenance to guarantee the effectiveness. Heat pump installation takes in-depth expertise due to the complicated system set-up. It is essential to hire an experienced technician to install a heat pump correctly.

 

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