Words we use

Trade words on your quote and project page, in plain terms.

Heat pump: A machine that moves heat instead of making it. In winter it brings heat in from the outside air. In summer it takes heat out.
Mini-split (ductless heat pump): A heat pump with an outdoor unit and one or more indoor units, joined by small lines instead of ducts.
Indoor head (indoor unit): The part of a mini-split that hangs inside a room and blows warm or cool air.
BTU and tons: BTU is a measure of heat. Heating and cooling is sized in BTU per hour. One ton is 12,000 BTU per hour.
Design load: The heat a room needs on a very cold day for your area, or the cooling on a very hot one. Equipment is sized to cover it.
ACCA Manual J: The standard way to work out how much heat and cooling a home needs. ACCA is the trade group of air conditioning contractors that wrote it.
Climate zone: The energy code's map of U.S. climates, from hot (low numbers) to very cold (8). It sets how much heat a home needs.
Refrigerant (and A2L): The fluid a heat pump moves between its units to carry heat. A2L refrigerants are newer ones that can burn a little, so installers get extra training.
EPA 608 certification: The federal card a tech needs to work on refrigerant. EPA is the U.S. Environmental Protection Agency.
Line set (line run): The pair of covered copper tubes that carry refrigerant between the outdoor unit and an indoor unit. The line run is how far they go.
Pre-charged (quick-connect): It comes from the factory already full of refrigerant. The lines click together, so no one works on the refrigerant at your home.
HVAC: Heating, ventilation and air conditioning. An HVAC license covers heat pump and furnace work.
Breaker, amps and 2-pole: A breaker is a switch in your panel that cuts power if a circuit draws too much. Amps measure current. A 2-pole breaker serves a 240-volt circuit and takes two spaces.
kW and kWh: A kilowatt (kW) is 1,000 watts of power. A kilowatt-hour (kWh) is that much power for one hour; it's what your electric bill counts.
Level 2 charger: A 240-volt home charger for an EV. It charges much faster than a regular outlet.
J1772 / NACS: The two EV charging plugs in North America. NACS is the plug Tesla started; J1772 is the one most other EVs have used.
First-hour rating and UEF: First-hour rating is how much hot water a heater can give in one busy hour. UEF is its federal efficiency rating; higher uses less energy.
Standpipe: The open drain pipe a washing machine empties into.
Rough-in: The first stage of an install: equipment mounted and lines run, before the final hookups.
Commissioning: Starting a new system and testing it, with the readings written down, to show it was put in right.
Pressure and vacuum tests: The tech fills new lines with nitrogen and watches for a drop, which would mean a leak. Then they pump out the air and water, checked in microns, before refrigerant flows.
Permit: Your city's OK to do the work, often with an inspection after. Who gets each permit is shown on your quote.
Change order: A written change to the job's work or price. Nothing extra is done or charged until you approve it.
Allowances and not-to-exceed prices: Some things can only be counted on site. Each has a set price per item and a cap, so the price can't go past the most you saw without your OK.
Contractor of record and qualifier: The licensed business that answers for the work by law. On Ducto that's always your installer, never Ducto. The qualifier is the license holder named for your job.
SEER2 and HSPF2: U.S. ratings for how much power a heat pump uses to cool (SEER2) and to heat (HSPF2). A higher number uses less power.
DOE: The U.S. Department of Energy.