Comfort terms, explained.
Plain-English definitions for the heating, cooling, plumbing, and indoor-air terms you'll see on an estimate — so you can ask sharper questions and recognize honest answers.
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Heat exchanger
The metal chamber inside a furnace where combustion gases transfer heat to the air your blower pushes through …
DefineCondenser coil
The outdoor coil in your AC or heat pump that releases the heat pulled out of your home. Around Evansville and …
DefineEvaporator coil
The indoor coil that sits above your furnace and absorbs heat from the air moving through your ducts. It's als …
DefineCompressor
The motor in the outdoor unit that pressurizes refrigerant and drives the entire cooling cycle. It's the most …
DefineRefrigerant
The chemical fluid that cycles between liquid and gas inside your AC or heat pump to move heat from inside to …
DefineR-410A
The refrigerant used in most residential systems sold from about 2010 through 2024. It's being phased out, so …
DefineR-454B
The lower-global-warming refrigerant replacing R-410A in new residential equipment starting in 2025. It runs a …
DefineSEER2
The current efficiency rating for cooling equipment — higher numbers mean less electricity used to deliver the …
DefineAFUE
Annual Fuel Utilization Efficiency — the percentage of a furnace's fuel that actually becomes heat in your hom …
DefineHSPF
Heating Seasonal Performance Factor — the efficiency rating for a heat pump in heating mode. It matters most i …
DefineBTU
British Thermal Unit — the basic unit of heat used to size heating and cooling equipment. One BTU is roughly t …
DefineTon (of cooling)
A cooling-capacity unit equal to 12,000 BTUs per hour. Most homes around Haubstadt and Evansville need 2 to 4 …
DefineManual J load calculation
The industry-standard math for sizing a heating and cooling system based on your home's square footage, window …
DefineStatic pressure
The resistance your blower has to push against to move air through your ducts and filter. High static pressure …
DefineVariable-speed blower
A furnace blower that adjusts its speed in small steps instead of running flat-out or off. It moves air more q …
DefineTwo-stage furnace
A furnace that runs on low fire most of the time and only kicks to high fire when it's truly cold outside. You …
DefineSingle-stage AC
An air conditioner that runs at one fixed capacity — full blast or off. It's the simplest and least expensive …
DefineHeat pump
An electric system that moves heat instead of burning fuel — cooling your home in summer and heating it in win …
DefineDual-fuel system
A heat pump paired with a gas furnace so the system picks whichever is cheapest to run at the current temperat …
DefineMini-split (ductless system)
A heating and cooling system that uses small wall-mounted indoor units instead of ductwork, with one outdoor c …
DefineLine set
The pair of insulated copper tubes that connect your outdoor condenser to the indoor evaporator coil and carry …
DefineCondensate drain
The PVC line that carries water away from your evaporator coil as humidity condenses out of the air. In our hu …
DefineThermostat cycling
How often your system turns on and off across an hour. Short cycles — under about 10 minutes — usually mean an …
DefineWater-heater anode rod
A sacrificial metal rod inside a tank water heater that corrodes on purpose so the tank itself doesn't. Swappi …
DefineExpansion tank
A small tank installed near your water heater that absorbs the pressure spike when water heats up and expands. …
DefinePressure regulator (PRV)
The brass valve where your main water line enters the home that drops municipal pressure down to a safe 60–75 …
DefineSump pump
The pump in a basement pit that lifts groundwater out before it floods the floor. With Vanderburgh County aver …
DefineSewer cleanout
A capped vertical pipe that gives a plumber direct access to your main sewer line for snaking or camera inspec …
DefineBackflow prevention
A valve that stops contaminated water — from irrigation lines, boilers, or flooded fixtures — from being sucke …
DefineP-trap
The U-shaped bend under every sink, tub, and shower that holds a small amount of water to block sewer gas from …
DefinePolybutylene piping
A gray plastic supply pipe installed in homes from roughly 1978 to 1995 that fails from the inside out, often …
DefinePEX piping
A flexible plastic supply pipe that's now the dominant choice for new construction and repiping. It handles fr …
DefineCopper pipe pinhole leak
A tiny leak that develops when something in the water — usually pH or chloride — slowly erodes a copper pipe f …
DefineTankless water heater
A water heater that heats water on demand instead of keeping a 40- or 50-gallon tank hot all day. It saves spa …
DefineRecirculation pump
A small pump that keeps hot water moving in a loop so it's ready at the tap without waiting. Worth it in large …
DefineDrain snake vs. hydro-jet
A drain snake punches a hole through a clog so water can pass; a hydro-jet uses high-pressure water to scour t …
DefineSoft water vs. hard water
Hard water carries dissolved minerals — mostly calcium and magnesium — that scale up water heaters, fixtures, …
DefineWater softener regeneration
The cycle where a softener flushes the captured hardness minerals out and recharges its resin bed with salt. M …
DefineSediment filter
A whole-house cartridge filter that catches sand, rust, and grit before they reach your fixtures and appliance …
DefineMERV rating
A 1-to-16 scale measuring how well an air filter captures particles — higher numbers catch smaller particles. …
DefineHEPA filter
A high-efficiency filter that captures 99.97% of particles down to 0.3 microns — the standard used in hospital …
DefineUV germicidal light
A UV-C lamp installed in the air handler or near the evaporator coil that disrupts mold and bacteria growing o …
DefineIAQ (indoor air quality)
An umbrella term covering particulates, humidity, ventilation, and contaminants like VOCs and CO inside your h …
DefineDew point
The temperature at which water vapor condenses out of the air. Summer dew points in Southwest Indiana average …
DefineVentilation rate
How much fresh outside air is brought into the home, usually expressed in air changes per hour or cubic feet p …
DefineHRV / ERV
Heat-recovery and energy-recovery ventilators bring fresh outside air into the home while transferring heat — …
DefineHumidity control
Managing indoor moisture so it stays roughly 30–50% year-round. Too high in summer and you get mold and that c …
DefineSmart thermostat
A connected thermostat that learns your schedule, adjusts to outdoor conditions, and reports usage. The saving …
DefineZone control
Dividing your home into separately controlled areas using motorized dampers in the ducts and multiple thermost …
DefineNo terms match your search.
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