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Confused about many of the terms used when choosing HVAC equipment? Maybe this will help!
ABOVE GROUND STORAGE TANK (AST) - A tank which is "90% above the surface of the ground, that is used by a fuel dealer to dispense gasoline or diesel fuels.
ADD-ON COOLING - Installing cooling into an existing warm air system is often referred to as an "add on". Adding cooling to a heating system involves the installation of an evaporator or cooling coil on the furnace, a condenser outside, and the refrigerant lines to connect them. Add-on cooling generally uses your existing duct work and vents to distribute the conditioned air.
AIR FILTERS - Electronic, pleated and electrostatic filters are common upgrades to the throw-away, fiberglass filter your system probably uses now to remove dust and dirt from circulated air. Depending on your needs, a new type of filter may improve the air quality in your home.
AFUE - Acronym for Annual Fuel Utilization Efficiency. The AFUE rating may be used to compare the efficiency of furnaces. The higher the AFUE rating, the more efficient the unit. The AFUE rating is really the percent of fuel that is not wasted when the useable heat is produced. For example, older furnaces might have an AFUE of 65 or 70 percent. This means that if you buy $1.00 of fuel, $0.65 or $0.70 of that fuel goes to heat the home, the rest is wasted by the furnace and escapes through the flue (vent).
BOILER - (A.K.A. Hydronic system) A boiler produces steam or hot water to be distributed through a network of piping that flows to baseboard or radiators to heat the home. Boilers can be constructed of steel or cast iron and are made up of sections, which are large hollow rings stacked together, like a box of donuts. The water to be heated flows inside the rings, and the burner is mounted to blast its flame into a firebox (sometimes called a refractory) fitted into the hollow created within the sections. Steel boilers can be of the same design or be of stamped steel welded together to form the sections or water chambers. Water expands and contracts as it is heated and cooled, necessitating an expansion tank. Circulators are needed for each loop, or one circulator can be used with zone valves in a hot water system. A hot water boiler is filled with water, and a steam boiler is not. Steam boilers are identical to hot water boilers in construction, but operate at different water levels. In order to make steam, the water is kept below the top of the water jacket. A float valve with a sight glass automatically regulates the water level. Steam moves through the pipes to the radiators under its own pressure. As the steam passes though a radiator it cools and condenses into water, then gravity returns the water to the boiler to repeat the cycle. Many of the hot water boiler controls that are not needed include the circulator, flow check valve, and automatic bleeders.
CENTRAL AIR CONDITIONING - Residential central air conditioning systems that need to cool and dehumidify uses a condenser, evaporator coil, and refrigerant piping to operate. The means of moving the air might differ (furnace, air handler, etc.), but the principal is the same for all split systems. The term "split" refers to the physical separation of the condenser and the evaporator. This is in contrast to a window or wall air conditioner in which they are "packaged" together. The refrigerant is compressed and run through a series of tubes to remove as much heat as possible, then piped to an evaporator coil as a warm liquid. Expansion of the compressed liquid causes it to cool, and as the air passes over the coil, heat is extracted. The cool liquid becomes a cool gas as it gathers heat from the air, and is drawn back to the compressor to start the procedure again. As the air passes over the evaporator coil and cools, moisture in the air condenses and drains off as condensate. The conventional central air system is considered low velocity. In this type of system, the air temperature will drop some 15 to 18 degrees F when it passes through the cooling coil, and a 6 inch round duct will deliver approximately 2,500 BTU's of cooling.
CONDENSER/CONDENSING UNIT -The condensing unit is located outside of your home. This unit contains the compressor, a condenser coil, a fan motor and electrical components necessary for its operation. During the cooling process, the condenser performs the function of transferring heat from your home to the outside air. The efficiency of the air conditioning system is primarily determined by the condensing unit.
CONSUMPTIVE USE - Fuel oil used exclusively for area heating and/or heating of domestic water on the premises where stored.
DEGREE DAYS - Degree days are a measure of how cold it is outside - and, consequently, of customer demand for heating fuel. As an average homeowner, the amount of fuel that you use has a big impact on how much you pay. Conservation and mechanical efficiency will reduce usage. But nothing effects usage more than the weather. Our Bioheat™ Heating Oil delivery system relies upon degree days to project individual customer demand and keep tanks full without excessive small deliveries. For this reason Shipley Energy has a degree day clock on the roof of our King St. facility. Although, granted, this is not real exciting stuff...sharing our downtown York degree day count is something unique that we can offer to an energy information site. Shipley's degree day clock measures how cold it is outside from September through May. The clock records the daily high and daily low temperatures each day. The median average temperature of the day subtracted from 60 is the number of degree days for that day.
DOMESTIC HOT WATER- Domestic hot water (used for washing, cooking, etc.) is produced in several ways. A separate oil, gas, or electric water heater is the most common method. Other ways include the use of a tankless coil (a coil of copper tubing with aluminum fins attached) that is immersed into the water jacket of a hot water or steam boiler to allow the heat exchange and using a "hot water maker" which is a storage tank with a coil inside through which hot water from the boiler is circulated for the heat exchange. Hot water cannot be drawn directly out of the boiler because it may contain anti-freeze or corrosion protecting chemicals.
DUCTWORK - The ductwork in your home is the system by which "conditioned" air travels from the source to the areas to be temperature controlled. This system will be based on the cfm output of the blower, and the total cfm will have to be distributed proportionally to the rooms according to their needs. The furnace will have a specification sheet which will list the various blower speeds and outputs. If you have had problems heating or cooling areas of your home, duct modifications may be needed to solve the problem.
EVAPORATOR COIL - The evaporator coil is located inside the home. The evaporator coil is also referred to as the cooling coil or the evaporator. The evaporator coil can be mounted directly on top or beneath of a furnace depending on the furnaces airflow. If your system is located in an attic or crawlspace, the evaporator coil can be located on the outlet side of a furnace or attached to an air-handler. When cooling your home, the evaporator performs the function of absorbing the heat from the air in the house. For efficient operation, your evaporator coil and condensing unit should be a matched set.
EXISTING FACILITY - A tank system whose construction, installation, or operation began prior to December 31, 1986.
FLAMMABLE AND COMBUSTIBLE LIQUIDS - A flammable liquid is any liquid having a flash point below 100°F. Flammable liquids are known as Class I liquids and are divided into the following classifications: Class IA, Class IB and Class IC (depending on flash point levels). A combustible liquid is any liquid having a flash point at or above 100°F. Combustible liquids are also known as Class II or Class III liquids.
FURNACE - The furnace uses Bioheat™ Heating Oil, propane, or natural gas to produce a flame which heats air moving through it's heat exchanger. The furnace also contains a blower fan which moves the air through a system of air ducts for both heating and cooling the home.
HEATING SYSTEM - The heating system (boiler or furnace) simply heats up water or air respectively, and then moves that heated water or air (or steam) around the house. It's really that simple. However, the technology behind this process is pretty complicated, which means that a professional must perform most maintenance tasks associated with it.
HEAT PUMP - A heat pump is an appliance that extracts heat from one environment and discharges it into another. In heating mode, a heat pump will collect heat from the outdoor unit (condenser), and discharge it inside through the air handler. With the help of a reversing valve, the flow of refrigerant moves in the opposite direction and heat is extracted from the air handler and discharged outside, creating air conditioning. The basic components are: the air handler; comprised of a cabinet, blower, evaporator coil, and controls, the condenser or outdoor unit, and piping to create a closed loop of refrigerant between the two. In some areas the heating demand can be two or three times the cooling demand. Because a heat pump’s efficiency drops as the outside temperature goes down, electric heating elements will be installed as a backup to assist the heat pump when needed.
HUMIDIFICATION - Let's go with the notion that temperature is actually a container that we'll call a bucket. The higher the temperature, the bigger the bucket. The bigger the bucket, the more water it will hold, and vice versa. The amount of water in the bucket effects our sense of comfort. Too much water is uncomfortable, as is too little. Because temperature dictates the quantity of water in the bucket, too little usually occurs in winter, and too much occurs in summer. Adding more water into the bucket is called humidification. Emptying the bucket is called dehumidification. Because a central heating and cooling system is circulating and treating the air in your house, it becomes a convenient place to alter the water content of your air as well as the temperature. Dehumidification is a natural byproduct of a well designed cooling sytem. The cooler air has a smaller bucket and cannot carry as much water as before it was cooled, so it condenses inside your cooling system with little extra effort. Raising the water level in the bucket is not a natural side effect of the heating system, and requires a special effort. A humidifier is the machine that performs this function.
NEW OR REPLACEMENT FACILITY - A tank system whose construction, installation or operation commenced on or after December 31, 1986.
REFRIGERANT LINES - The refrigerant lines connect the condenser to the evaporator coil in AC and Heatpump "split" systems. This (usually copper) tubing carries the refrigerant, which is under pressure (as much as 350 pounds per square inch) to and from the compressor.
SEER - Acronym for Seasonal Energy Efficiency Ratio. The SEER rating may be used to compare the efficiency of condensing units. The higher the SEER rating, the more efficient the unit. The SEER rating of a condensing unit will depend on the particular evaporative coil to which it is connected
SELF CONTAINED UNITS - Self contained or ptu’s (packaged terminal units) are labeled as such because the condenser, furnace, evaporator coil, and blower are contained in one large cabinet. The most common are rooftop units but also includes mobile home air conditioners. Heating only, cooling only, or heating and cooling can be obtained from these machines. Heat can be from any fuel (gas, oil, electricity, or heat pump), and air conditioning will be electric. Designed originally for commercial applications, their versatility has created a demand for residential use; and smaller, quieter machines are produced for the home. Rooftop installations that are ducted out of the bottom require a curb, which not only raises the unit up off the roof but has framework to support and fasten the ductwork to. Mobile home units are usually tied in with the trailers existing heating system by use of flexible ducts and a dampering system.
THERMOSTAT - The thermostat is a device used to detect temperature changes for the purpose of maintaining the temperature of an enclosed area. In a system including relays, valves, switches, etc., the thermostat generates signals, usually electrical, when the temperature exceeds or falls below the desired value. Programmable thermostats can automatically reduce or raise temperatures for added comfort at pre-set times for example.
UNDERGROUND STORAGE, UNDERGROUND STORAGE TANK (UST) - An underground storage tank, connected underground piping, underground auxiliary equipment, and containment system if any. 10% or more of the tank volume and piping must be underground. A UST does not include a freestanding container within a building.
Basic design of an indoor home heating tank:
(outdoor tanks vary slightly)
For additional information on oil tanks and regulations associated with them, please visit the website of Pennsylvania's Department of Environmental Protection: |
