30 Plumbing Terms Every Kent Homeowner Should Know

For many Kent homeowners, plumbing can feel like a foreign language. When a plumber visits your home or you start researching a plumbing issue, you’re likely to come across terms that sound unfamiliar. Understanding the basic plumbing vocabulary not only helps you communicate better with professionals but also empowers you to make confident decisions about repairs, maintenance, or upgrades.

At CPR Rooter, we believe that a well-informed homeowner is a stronger homeowner. That’s why we’ve created this simple yet comprehensive guide to the 30 most important plumbing terms every Kent homeowner should know — explained in everyday language so anyone can understand.

Water Main

The water main is the primary pipe that brings fresh, potable water from the city’s municipal supply into your home. It typically runs underground and connects directly to your home’s plumbing system. Knowing its location is critical in emergencies like pipe bursts, as shutting off the water at the main can prevent extensive damage. Over time, older water mains may corrode or leak, and it’s important to have them inspected periodically by a professional plumber.

Shut-Off Valve

A shut-off valve allows you to stop the flow of water either to your entire home or to specific fixtures such as sinks, toilets, or appliances. There are main shut-off valves (usually near where the main water line enters your home) and fixture-specific shut-offs. These valves are essential during plumbing repairs, emergencies, or maintenance. Shut-off valves can corrode or become stuck over time; it’s wise to test and inspect them annually to ensure proper function.

P-Trap

A P-trap is the curved section of pipe located beneath sinks and other drains. It traps a small amount of water to act as a seal, preventing sewer gases from coming back up into your home. This simple mechanism is crucial for health and hygiene. P-traps can become clogged with debris, hair, or soap scum, and may need occasional cleaning. If not used for long periods, the water can evaporate, breaking the seal.

Drain-Waste-Vent (DWV) System

This system is responsible for removing wastewater and sewer gases from your home. It includes drain pipes (for water flow), waste pipes (for sewage), and vent pipes (to allow air in and prevent suction or pressure issues). A properly functioning DWV system ensures your water drains quickly and your home stays odor-free. Poor venting or clogging in this system can lead to slow drainage and dangerous gas buildup.

Sump Pump

A sump pump is typically located in a basement or crawl space and helps remove excess groundwater, especially during heavy rains. It sits in a sump pit and activates automatically when water levels rise. Sump pumps are essential in flood-prone areas of Kent. They should be inspected annually, and many homeowners install backup battery systems to ensure operation during power outages.

Water Heater

A water heater is the device responsible for heating water for your household. It can be gas or electric, and either tank or tankless style. Tank heaters store heated water, while tankless models heat water on demand. Over time, sediment buildup can affect efficiency, so annual flushing is recommended. Most tank water heaters last 8-12 years.

Tankless Water Heater

Tankless heaters heat water instantly as it flows through the system, making them more energy-efficient and compact. These are ideal for smaller homes or those looking to save energy. They require descaling at least once a year to prevent mineral buildup. Tankless units can last 15-20 years with proper care.

Anode Rod

This is a critical component inside a tank water heater, designed to attract corrosive elements and protect the tank lining. Over time, it corrodes instead of your tank. Anode rods should be inspected every 2-3 years and replaced when significantly worn. Replacing the rod can extend the life of your water heater significantly.

Water Pressure Regulator (PRV)

A PRV is a valve that reduces and stabilizes incoming water pressure to safe levels. High water pressure can strain your plumbing and appliances. The ideal home water pressure is between 40-60 PSI. If your pressure is too high or fluctuates, the PRV may need adjustment or replacement.

Backflow Preventer

This device prevents contaminated water from flowing backward into your clean water supply. It’s especially important in sprinkler systems or irrigation setups. Some homes have built-in backflow prevention for safety. These devices should be inspected annually to ensure they function properly.

Water Softener

A water softener removes hard minerals like calcium and magnesium from your water. Hard water is common in Kent and can cause buildup in pipes and appliances. A softener protects your plumbing and extends the life of water-using equipment. Salt levels should be checked monthly and the system cleaned regularly.

Aerator

An aerator is a small screen at the end of a faucet that mixes air with water to reduce flow while maintaining pressure. It improves water efficiency and reduces splashing. Aerators can get clogged with sediment and should be cleaned or replaced every few months.

Flapper Valve

This rubber component in your toilet tank lifts during a flush and seals the water afterward. A worn flapper is the most common reason toilets run continuously. Flappers should be checked annually and replaced if they no longer create a watertight seal.

Cleanout

A cleanout is an access point in your plumbing system, usually located outside or in a basement, that allows plumbers to clear clogs and debris. Cleanouts make sewer line maintenance and inspection much easier. If your home doesn’t have an accessible cleanout, installation may be recommended.

Trap Arm

The trap arm connects the P-trap to the wall drain. It must be properly sloped to allow water to drain efficiently. Poor alignment or slope can cause frequent clogs or sewer gas leaks. Trap arms are often overlooked but are essential to a well-functioning drain system.

Air Gap

An air gap prevents contaminated water from siphoning back into your clean water supply. It’s common in dishwashers and some faucet designs. This simple device uses gravity and space to create a barrier between waste and potable water. Air gaps should be checked periodically for blockages or leaks.

Greywater

Greywater refers to used water from sinks, showers, and laundry — not including toilet waste. Some systems repurpose greywater for irrigation. Greywater reuse can reduce water bills, but it must be handled properly to avoid health risks.

Blackwater

Blackwater includes sewage from toilets and kitchen sinks and must be treated before disposal. It contains pathogens and cannot be reused without professional treatment. Understanding this difference is essential for safe waste management in your home.

Hose Bib

Also called an outdoor faucet, this fixture is used to connect garden hoses or irrigation systems. Hose bibs are prone to freezing in winter and should be shut off and drained before cold weather. Freeze-proof models are recommended for Kent homes.

Expansion Tank

This small tank is attached to your water heater system to absorb excess pressure from thermal expansion. It prevents damage to pipes and appliances. If your system lacks an expansion tank, it may not comply with modern plumbing codes. These tanks typically last 5–10 years.

TPR Valve (Temperature-Pressure Relief Valve)

This safety device on water heaters automatically releases water if internal temperature or pressure gets too high. It’s a critical feature to prevent explosions. Test it annually to ensure it’s not stuck or leaking.

Pipe Joint Compound

Also called plumber’s dope, this sealant is used on threaded pipe fittings to prevent leaks. It stays soft and flexible, allowing easy future disassembly. It’s commonly used in gas and water lines.

Plumber’s Snake

Also called a drain auger, this flexible tool breaks up clogs deep in pipes that plungers can’t reach. Available in manual and motorized versions. Snaking your drain is more effective than chemical cleaners.

Water Hammer

A loud banging noise in your pipes caused by a sudden stop in water flow. It can damage pipe joints over time. Installing water hammer arrestors helps absorb the shock and protect your plumbing system.

Pipe Insulation

Material wrapped around pipes to reduce heat loss and prevent freezing. Especially useful in crawl spaces and outdoor walls. It’s a simple, low-cost way to increase energy efficiency and reduce risk of pipe bursts.

Fixture Unit

A standardized measurement of a plumbing fixture’s water usage and drainage requirement. Used in system design to size pipes and drainage components. Knowing fixture units helps ensure your system is balanced and efficient.

PVC (Polyvinyl Chloride)

A common white plastic pipe used for cold water and drain lines. Lightweight and affordable, but not suitable for hot water. Often used in venting and sewage systems.

CPVC (Chlorinated Polyvinyl Chloride)

Similar to PVC but chemically treated to handle hot water. It’s durable, affordable, and easier to work with than copper. Widely used in residential hot and cold water lines.

Cross Connection

Any potential point where contaminated water could enter your clean water system. Common in hose bibs or irrigation systems. Backflow prevention devices are used to eliminate these risks.

Pipe Thread Seal Tape (Teflon Tape)

A thin white tape wrapped around threaded pipe joints to prevent leaks. Commonly used in water, air, and gas line connections. Replace it anytime you disconnect and reconnect plumbing joints.

Call CPR Rooter – Your Kent WA Plumbing Experts

We hope this detailed glossary of plumbing terms has helped you feel more confident about your home’s plumbing system. At CPR Rooter, we’re committed to making plumbing simple and accessible for every Kent homeowner. If you have questions, need service, or just want expert advice, call us today at (425) 647-5800 — we’re always here to help with reliable, affordable plumbing solutions.