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We realize some of the terminology in our industry can be confusing and difficult to understand. Here is a glossary of common terms to help you out.

Jump to: Plumbing | Heating | Cooling | Indoor Air Quality | Electrical


Plumbing Terms

  • Access panel – A removable cover or door that allows access to plumbing components in walls, ceilings, or other areas.
  • Aerator – A threaded faucet attachment that directs the flow of water, prevents splashing, and limits output.
  • Area drain – A drain that collects runoff or wastewater for a given area and directs it to the main sewer or wastewater system.
  • Backflow preventer – A valve assembly that prevents water from flowing back into the potable water system from a system with higher pressure, such as a fire sprinkler, boiler, or kitchen sprayer.
  • Bypass valve – A valve that allows water to bypass the water softener for uses that require no softening.
  • Direct drain – A drain that flows into the waste arm with no air drop.
  • Elongated water closet – A toilet with an elongated, elliptical bowl.
  • Flapper – A valve between the tank and bowl of a toilet that is pulled up to release water from the tank to the blow and drops back down to allow the tank to refill.
  • Gasket – A rubber or paper seal that prevents leaks between pipes or machined surfaces.
  • Hard water – Water that has high mineral content, such as calcium and magnesium, leading to mineral deposits, plumbing clogs, soap scum, and other problems.
  • Power vent water heater – A water heater that uses a fan to vent combustion air.
  • PVC – Plastic pipes made from polyvinyl chloride that are often used for potable water, drain, and vent systems.
  • Soft water – Water with minimal calcium and magnesium content.
  • Standpipe – A vertical pipe used to store or pressurize water, such as in a fire sprinkler system. It can also refer to a washing machine drain pipe.
  • Stop and waste – A hose bibb that can be drained to prevent freezing.
  • Sump pump – A pump used to remove water from a sump pit, which is often installed in basements or other below-grade areas to remove groundwater accumulations and prevent flooding.
  • Water meter – A meter installed by your local utility company or municipality that measures water usage for billing purposes.

Heating Terms

  • Boiler – A heating system that heats water or creates steam for heating through radiators, baseboard heaters, radiant flooring, fan coils, or air handlers.
  • BTU – British thermal units are a measurement of heat output equivalent to the heat required to increase the temperature of a gallon of water by one degree Fahrenheit.
  • Flue – The pipe required to vent combustion gases from a water heater, furnace, or boiler to the outdoors.
  • Heat loss – The amount of heat lost in a conditioned space, measured in BTUs.
  • Manual/auto zone duct – Ducts that control airflow to different zones, either manually or automatically, through sensors and actuators.
  • Radiant floor heating – Piping installed beneath a finished floor that carries warm water for heating a room.
  • Secondary heat exchanger – A second heat exchanger that extracts heat from the combustion exhaust of a furnace or boiler for maximum efficiency.
  • Volume damper – A plate that opens or closes to adjust airflow in a duct for a particular zone.
  • Warm-air plenum – The cabinet that collects the warm air from the furnace and distributes it to the supply ducts.
  • Zoned system – A heating or air conditioning system that offers independent control of temperatures in each room or zone using airflow dampers or hydronic heating valves.

Cooling Terms

  • Condensation line – A pipe that allows condensed water to drain away from the evaporator to either the outdoors or the home’s drain system.
  • Condenser – The outdoor coil of an air conditioning system that releases heat to the outdoor air.
  • Evaporator or A-coil – The interior portion of an air conditioner that absorbs heat from your home. It is typically installed in the furnace or a stand-alone air handler.
  • Plenum – A box or cabinet that connects multiple supply or return ducts to an HVAC system.
  • SEER – The seasonal energy efficiency ratio is a measure of an air conditioner’s energy usage and relative efficiency over a cooling season.

Air Quality Terms

    • Category One – The Minnesota codes that govern indoor air quality, ventilation, and moisture control in new homes.
    • Electronic air cleaner – An air cleaner that uses a negative charge to attract pollutants like dust and pollen particles from the air and collect them on charged metal plates.
    • Heat recovery ventilator (HRV) – An air-exchange ventilation system that uses heat exchangers to reclaim heat from the air that is exhausted outdoors.
    • HEPA filter – HEPA, or High-Efficiency Particulate Air, is a category of filters that are able to trap 99.97% of particles that are 0.3 microns.
    • Humidifier – A device that uses heat or vibration to evaporate water and add humidity to dry air.
    • IAQ – Indoor air quality represents the air quality or the amount of pollution contained in the indoor air.
    • MERV Minimum Efficiency Reporting Value, or MERV, is the unit of measure for an air filter’s ability to capture larger particles.
  • Source point – The source of air for a ventilation system, such as a return duct.
  • Vent range hood – A hood that gathers exhaust fumes from a stove and vents them outside.
  • Water panel – A panel outside a humidifier that absorbs moisture.

Electrical Terms

  • AC – An electric current that changes direction many times per second, the common form of electric power delivered to your home or business and used for fixtures, for fans, or via wall sockets.
  • Amperage – A measurement used for the flow of electrons or electrical current. Amperage measures the volume of electrons.
  • Circuit breaker – A device designed to shut off an electrical circuit if there is too much current. Circuit breakers fulfill the same purpose as a fuse, but can be reset without being replaced.
  • DC – An electric current that flows in a single direction. Commonly seen in batteries, as it’s used to charge them and is the type of current provided by them.
  • Dimmer – Switches connected to a light fixture that can lower the brightness of light by changing the voltage waveform.
  • Electrical load – Any devices or parts of a circuit that consume electric power, such as appliances or lights.
  • Electrical panelAlso called a breaker panel, service panel, breaker box, or load center. The steel cabinet or box in your home that contains your circuit breakers.
  • Fuse – An electrical safety device, usually a delicate metal wire or strip, which melts when too much current flows through it to stop the current.
  • GFCI – A ground fault circuit interrupter, a type of circuit breaker that shuts off electric power if it senses an imbalance in outgoing and incoming current. Used to protect against electric shocks and fires, most commonly seen in wiring in bathrooms and kitchens.
  • Low voltage – Refers to systems that use less than 50 volts of electricity, such as doorbells or thermostats.
  • Meter – A device that measures the amount of electric energy that a residence, business, or device consumes.
  • Recessed lighting – A light fixture installed into a hollow opening, resulting in more concentrated light shining down out of the hole.
  • Surge protector – An appliance or device that protects the devices connected to it from voltage spikes that might damage them.
  • Voltage – A measurement used for the flow of electrons or electrical current. Voltage measures the potential difference that forces electrons to flow.
  • Wattage – Wattage describes the rate of power flow. It’s a simple result of amps x volts. Think of it as the power you get from a certain amount of water being pushed with a certain amount of pressure. Alternatively, think of the power of a vehicle in motion, considering its weight and the engine pushing it.

For help with these terms or any heating, air conditioning, or plumbing problems that you may have, contact our team today. Call (612) 440-3124 or contact us online for service anywhere in Minneapolis, St. Paul, or the greater Twin Cities area.

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