Understanding your home's systems

• A. Volt
• B. Ampere ✓
• C. Ohm
• D. Watt

Why: Electrical current is measured in amperes (amps). Volts measure voltage, ohms measure resistance, and watts measure power.

• A. It stores electricity for later use
• B. It converts AC power to DC power
• C. It automatically interrupts the current when it exceeds a safe level ✓
• D. It measures how much electricity the home uses

Why: A circuit breaker trips and cuts off power when current exceeds the rated capacity of the circuit, helping prevent overheating and fires.

• A. Black
• B. Red
• C. White
• D. Green or bare copper ✓

Why: Grounding conductors are typically green or bare copper. Black is usually hot, white is typically neutral, and red is often a second hot wire or a switched leg.

• A. 12 volts
• B. 120 volts ✓
• C. 240 volts
• D. 480 volts

Why: Standard residential outlets in North America provide about 120 volts. 240 volts is used for large appliances like dryers and ranges, and 12 volts is common in low-voltage systems.

• A. To increase the voltage of the circuit
• B. To provide a safe path for fault current to flow back to the source ✓
• C. To carry the normal load current to appliances
• D. To store excess electrical energy

Why: The ground wire gives fault current a low-resistance path to earth, which causes the breaker to trip quickly and reduces the risk of electric shock.

• A. To cool the air during summer months
• B. To generate heat that is distributed throughout the house ✓
• C. To filter dust and allergens from the air
• D. To control the humidity level inside the home

Why: A furnace generates heat, usually by burning fuel or using electric elements, and distributes that warmth through ductwork or other delivery systems to keep the home comfortable.

• A. It stores extra energy for later use
• B. It measures the air temperature and signals the system to turn heating or cooling on or off ✓
• C. It cleans the air by removing particles
• D. It pumps refrigerant through the outdoor unit

Why: A thermostat senses the current temperature and compares it to the desired setting. It then tells the heating or cooling equipment when to run so the home stays at the chosen temperature.

• A. To add moisture to dry indoor air
• B. To absorb heat from indoor air and release it outside ✓
• C. To burn fuel and produce warm air
• D. To filter pollen from incoming air

Why: Refrigerant cycles through the system, absorbing heat from indoor air as it evaporates and releasing that heat outdoors as it condenses, which is how the air conditioner cools the home.

• A. It makes the system run louder so you know it is working
• B. A clogged filter restricts airflow, reducing efficiency and potentially causing damage ✓
• C. It increases the temperature of the air being delivered
• D. It is only needed when the system is first installed

Why: A dirty filter blocks airflow, forcing the system to work harder, which wastes energy, raises costs, and can lead to overheating or breakdowns over time.

• A. Burning natural gas at high temperatures
• B. Both heating and cooling a home by moving heat rather than generating it ✓
• C. Operating without any electricity
• D. Removing carbon monoxide from the air

Why: A heat pump can reverse its refrigerant cycle to either extract heat from outdoor air to warm the home or remove heat from indoors to cool it, providing both heating and cooling from one system.

• A. To adjust the water pressure throughout the house
• B. To stop water flow to the entire home in an emergency or during repairs ✓
• C. To filter sediment from the incoming water supply
• D. To heat water before it reaches the fixtures

Why: The main shut-off valve controls the water entering the home, allowing you to stop flow to the whole house during leaks, burst pipes, or plumbing repairs.

• A. Cast iron
• B. Clay tile
• C. PEX (cross-linked polyethylene) ✓
• D. Galvanized steel with lead solder

Why: PEX is a popular modern choice for water supply lines because it is flexible, resists freezing better than rigid pipes, and requires fewer fittings.

• A. It controls how much hot water is used per minute
• B. It releases water if pressure or temperature inside the tank becomes dangerously high ✓
• C. It adds pressure to weak water lines
• D. It prevents cold water from entering the tank

Why: The pressure relief valve is a critical safety device that opens to release water and prevent the tank from rupturing when pressure or temperature gets too high.

• A. Brighter light fixtures
• B. A sudden unexplained increase in the water bill ✓
• C. Faster internet speeds
• D. Warmer rooms in the winter

Why: A sudden jump in the water bill without a change in usage often indicates a hidden leak, such as a running toilet or a break in a buried line.

• A. To increase the water temperature
• B. To remove sediment buildup that reduces efficiency and can damage the tank ✓
• C. To refill the tank with fresh water
• D. To test the electrical wiring

Why: Minerals and sediment settle at the bottom of the tank over time, which reduces heating efficiency, can cause noise, and may shorten the heater's lifespan. Flushing removes this buildup.

• A. To supply fresh water to fixtures under pressure
• B. To carry wastewater away from fixtures and vent sewer gases safely outside ✓
• C. To heat water for showers and dishwashers
• D. To filter rainwater for garden irrigation

Why: The DWV system removes used water and waste from plumbing fixtures and uses vent pipes to let sewer gases escape above the roof while maintaining proper pressure for drainage.

• A. It stores extra water for emergencies
• B. It regulates water pressure in the supply lines
• C. It holds a small amount of water that blocks sewer gases from entering the home ✓
• D. It catches small objects so they can be retrieved

Why: The curved P-shaped pipe always retains a small water seal, which prevents foul and potentially harmful sewer gases from rising into the living space.

• A. Water pressure in the shower is too high
• B. Multiple drains, such as sinks and tubs, drain slowly or gurgle at the same time ✓
• C. The water heater takes longer to warm up
• D. Light fixtures flicker when the dishwasher runs

Why: When several fixtures back up or gurgle together, the problem is usually in the shared main line rather than an individual drain, which signals a need for professional inspection.

• A. Turn the main water supply on and off
• B. Inspect, clear, or snake the main sewer line without tearing into walls or floors ✓
• C. Test the water heater's pressure relief valve
• D. Connect a garden hose to the home's water supply

Why: Cleanouts are capped openings on the drain line that provide direct access for cleaning blockages and inspecting the line, saving time and repair costs.

• A. Pouring cooking grease down the kitchen sink while it is hot
• B. Flushing flushable wipes and paper towels to keep the toilet clear
• C. Using a drain strainer and disposing of grease in a sealed container ✓
• D. Running the garbage disposal with large bones and fibrous food scraps

Why: Strainers catch hair and food solids, and disposing of grease in a container prevents it from solidifying in pipes, both of which are key to avoiding clogs.

• A. To heat the home evenly during winter
• B. To replace stale indoor air with fresh outdoor air ✓
• C. To filter water supplied to the home
• D. To lower the electricity bill directly

Why: Ventilation exchanges indoor air for fresh outdoor air, diluting pollutants, moisture, and odors that build up inside a home.

• A. Watching television
• B. Showering without an exhaust fan running ✓
• C. Reading books in the living room
• D. Charging phones

Why: Hot showers release large amounts of water vapor. Without exhaust ventilation, that moisture can lead to mold growth and damp surfaces.

• A. It cools the room by lowering the temperature
• B. It removes moisture, odors, and cooking pollutants at the source ✓
• C. It purifies the water in the sink
• D. It increases the humidity to prevent dry skin

Why: Exhaust fans capture humid air, grease, smoke, and odors right where they are produced, keeping them from spreading through the home.

• A. Excess humidity in the air
• B. Low oxygen levels from poor insulation
• C. A colorless, odorless gas produced by fuel-burning appliances ✓
• D. Dust particles from carpeting

Why: Carbon monoxide is colorless and odorless, so it cannot be detected by smell. Detectors are essential near fuel-burning appliances and bedrooms.

• A. Clogged filters make the air taste sweeter
• B. Dirty filters restrict airflow, reduce efficiency, and let more particles circulate ✓
• C. Filters must be changed to keep the thermostat working
• D. Old filters automatically add fragrance to the air

Why: A clogged filter forces the system to work harder, wastes energy, and allows dust and allergens to pass through and circulate in the home.

• A. Only in the kitchen, since most fires start there
• B. On the ceiling or high on a wall, and inside or near every sleeping area ✓
• C. Near the floor in each room, where smoke is thickest
• D. In the garage only, since it stores the most flammable materials

Why: Smoke rises and spreads along the ceiling, so alarms belong high on walls or ceilings. Installing them inside and outside sleeping areas gives early warning while people are sleeping, when they are most vulnerable.

• A. Once every five years, when the battery is replaced
• B. Only after a fire has occurred in the home
• C. Once a year, by replacing the battery every year
• D. Once a month by pressing the test button ✓

Why: Pressing the test button monthly confirms the alarm and its battery are working. Batteries should also be replaced at least once a year (or when the low-battery chirp sounds), and the entire unit should be replaced roughly every 10 years.

• A. Silence it, open a window, and continue as normal
• B. Turn on the ceiling fan to circulate the air and wait for it to stop
• C. Leave the home immediately, move to fresh air, and call emergency services ✓
• D. Check the battery first and go back to sleep if the battery is fine

Why: Carbon monoxide is odorless and colorless and can be fatal. If the alarm sounds, everyone should get outside into fresh air right away and call emergency services or the fire department from a safe location. Do not re-enter until cleared.

• A. Directly above the stove, where cooking gases rise
• B. Inside the furnace room, right next to the fuel-burning appliance
• C. On or near each level of the home and outside sleeping areas, at a height recommended by the manufacturer ✓
• D. Under a kitchen cabinet, where it is out of sight

Why: Carbon monoxide mixes with air fairly evenly, so alarms should be on every level and near sleeping areas. Placing one directly next to a fuel appliance can cause nuisance alarms, and placing it in a hidden spot can prevent you from hearing it.

• A. Pour water on it to cool the grease quickly
• B. Carry the flaming pan outside through the house
• C. Turn off the heat if it is safe to do so, then cover the pan with a fitted lid or use a fire extinguisher ✓
• D. Move the pan to the sink and turn on the faucet

Why: Water causes burning grease to spread violently. Cutting off the heat and smothering the flames with a lid (or using a Class K or ABC extinguisher if available) starves the fire of oxygen. Never carry a burning pan, and leave the area and call for help if the fire grows.

• A. Every 10 to 15 years
• B. Every 1 to 3 months ✓
• C. Once a year, regardless of use
• D. Only when the system stops working

Why: Air filters collect dust and debris that restrict airflow when clogged. Checking monthly and replacing every 1 to 3 months (sooner with pets or heavy use) keeps the system efficient and reduces strain on the blower motor.

• A. The water supply valve is fully open
• B. The flapper valve in the tank is worn or not sealing ✓
• C. The bathroom exhaust fan is malfunctioning
• D. The water heater temperature is set too high

Why: A worn or misaligned flapper lets water leak continuously from the tank into the bowl, causing the refill valve to keep running. Replacing the flapper is an inexpensive and common fix.

• A. Replace the breaker with a higher amp rating
• B. Disconnect all appliances on that circuit and reset the breaker, then add devices one at a time to find the overload ✓
• C. Leave it tripped until an electrician arrives
• D. Remove the fuse box cover and tighten all wires

Why: Repeated tripping usually means the circuit is overloaded or has a short. Isolating devices helps identify the culprit. Upsizing a breaker can create a fire hazard because the wiring may not be rated for the higher current.

• A. Flushing the tank annually to remove sediment ✓
• B. Adding ice cubes to the tank monthly
• C. Turning the thermostat to its maximum setting
• D. Insulating the cold water inlet pipe only

Why: Minerals in water settle at the bottom of the tank, reducing efficiency and causing overheating of the bottom of the tank. Flushing once a year removes sediment and helps the heater last longer.

• A. It emits a chirping sound at regular intervals ✓
• B. It has a green indicator light on
• C. It is mounted on the ceiling in a hallway
• D. It was installed more than a year ago

Why: A periodic chirp usually signals a low battery or a unit reaching end of life. Replace the battery promptly and test the alarm monthly. Most smoke alarms should be replaced entirely about every 10 years.