Plumbing Supply Glossary: 50 Terms Every Contractor Should Know

Introduction

Miss one fitting on a boiler repipe and your whole afternoon unravels. Grab a consumer-grade ball valve that sticks on start-up and you’ve just bought yourself a callback. Anyone who’s hustled on bid-build timelines or weekend emergencies knows the truth: the right supply house partnership is as critical as your torch and tape. Inventory depth, same-day reliability, and real technical guidance aren’t “nice-to-haves”—they’re the difference between profitable days and nights lost chasing parts.

Meet Mateo Abarca (38), a licensed plumber and owner of Abarca Mechanical in Albuquerque, NM. During a school hydronic retrofit, Mateo burned four hours driving to a big box for PEX tees that didn’t match the manifold threads, then waited two days on an online order that arrived with a counterfeit check valve. He called me frustrated; project downtime was chewing through his profit. Within one call, we matched the exact manifold spec, shipped the correct valves and PEX plumbing adapters from Plumbing Supply And More (PSAM) the same day, and attached installation guides to his order. He finished without a single call back.

This glossary is built for pros like Mateo—and for facility managers and capable homeowners who value precision. I’ve grouped 50 essential terms into 10 practical buckets. Each section shows you where specs matter, what to watch for in the field, and how PSAM helps you avoid expensive mistakes with a complete supply house solution: same-day shipping, real-time inventory, wholesale pricing, and licensed technical support. Use it on your next plumbing supply order, your next HVAC equipment tune-up, or that hydronic heating job that needs to be right the first time.

What you’ll learn:
The exact pressure, flow, and energy terms that drive system performance The joining methods and fittings that prevent leaks, code violations, and callbacks The hydronic and HVAC fundamentals that separate guesswork from craftsmanship Why partnering with PSAM pays you back in time, reliability, and total cost of ownership
Let’s get your glossary sharp and your sourcing dialed—so jobs move faster, margins stay healthy, and customers stay loyal.
#1. Hydraulics That Drive Performance – Static/Dynamic Pressure, Head, and Flow Basics You Size Against
Sizing pumps and pipes isn’t guesswork—it’s math tied to system behavior and code compliance. When you understand hydraulic terms, you eliminate noise, size accurately, and stop band-aiding poor designs in the field.

How PSAM makes it practical: PSAM aligns sizing to real-world conditions—line lengths, elevation, fittings, and fluid temps—then validates with compatibility charts and installation guides. Our expert staff (licensed plumbers and HVAC techs) keep you away from undersized pumps and noisy lines, while our real-time inventory shows exactly what’s on the shelf before you click purchase.

Mateo Abarca used this exact playbook to resolve a circulator whine that was really velocity noise. We recalculated plumbing supply and more https://www.plumbingsupplyandmore.com/ head and velocity targets, swapped to an ECM circulator with proper curve coverage, and ended the issue for good.
Static vs. Dynamic Pressure Static Pressure: The standing pressure in a closed system at rest. It impacts relief valves and expansion tanks. Dynamic Pressure: Pressure under flow; changes with pump operation and valve positions. Head (Feet of Head): The pressure expressed as vertical height; pump curves use head to show capacity. PSI: Pounds per square inch. Convert to head (ft) by PSI × 2.31 for water at ~60°F. ΔP (Delta P): Pressure drop across a component; key for verifying that balancing and control valves are set right. Flow, Friction, and Velocity Control GPM (Gallons Per Minute): Flow rate; pair to pipe size to maintain target velocities (typically 2–8 ft/s). Cv (Flow Coefficient): Valve flow capacity; higher Cv = lower pressure drop at set flow. Friction Loss: Pressure loss per length of pipe and through fittings; use charts and account for elbows/tees. FPS Velocity: Feet per second; control to reduce noise and erosion. Water Column (in. WC): Common in gas/low-pressure readings; 27.7 in. WC ≈ 1 PSI. Sizing Verification in the Field
Pro Tip: Verify ΔP across strainers and coils after cleaning. If static pressure is steady but dynamic pressure spikes, look for obstructions or incorrect balancing.

Key takeaway: Accurate hydraulics vocabulary leads to accurate sizing. PSAM backs you with calculators, pump curves, and fast ship times so you can set systems right the first time.
#2. Heat Transfer & HVAC Capacity – BTU, SEER2, and Delta T That Make Energy Math Work
Misunderstand capacity and you’ll underserve a space or waste energy. Get these right, and controls, coils, and equipment match the real load.

PSAM advantage: Whether you’re pairing coils to HVAC equipment or setting up an outdoor reset hydronic control, PSAM provides load guidelines, installation guides, and brand-specific data for verified matchups—no more guessing.

Mateo leaned on us to interpret coil ΔT and GPM for a classroom loop. That call prevented a repetitive no-heat complaint on cold mornings.
Fundamental Capacity Terms BTU/h: Heat transfer per hour; 1 ton cooling = 12,000 BTU/h. ΔT (Delta T): Supply-return temperature difference; hydronic design often targets 20°F, but 10–30°F may apply. SEER2: Seasonal efficiency for cooling; new standard more accurately reflects field conditions. CFM (Cubic Feet per Minute): Airflow; essential for coil performance, static pressure, and comfort control. GPM (Reinforced): For hydronic loops; pairs with ΔT to determine BTU/h (BTU/h ≈ 500 × GPM × ΔT for water). Competitor Comparison: PSAM vs. Home Depot and Amazon (Inventory, Expertise, Value)
Big box aisles carry basic capacitors, thermostats, and filter grilles—but not the deep bench of professional controls, hydronic valves, and ECM circulators that complex jobs require. Seasonal gaps are common, and matching coils to systems becomes “what’s in stock” rather than what’s correct. Meanwhile, general e-commerce marketplaces list thousands of third-party sellers, so you’re never fully certain of storage conditions or authenticity for compressors, controls, or line driers—high-risk components that don’t forgive mishandling.

Quality tells the real story. Consumer-grade fittings, bargain pumps, and unverified accessories lead to callbacks in tough environments. Without licensed pros at the counter, technical questions fall back to generic spec sheets. That’s not support—that’s guesswork. PSAM fields licensed technical support, verified manufacturer warranties, and a multi-warehouse distribution strategy that keeps critical gear in climate-aware storage. Your order isn’t a gamble; it’s a spec-backed match.

When you factor in same-day shipping, warranty protection, and real guidance, the total cost of ownership beats retail “savings” by a mile—worth every penny.
Field Validation Techniques Check coil performance: measure ΔT across coil and verify airflow with a manometer and anemometer. Adjust setpoints after balancing; overshooting ΔT wastes energy.
Key takeaway: Understand capacity terms, then let PSAM match equipment, controls, and accessories so systems run efficiently—without return trips.
#3. Drainage & Venting Fundamentals – Traps, Primers, and Air Gaps That Keep You in Code
Nobody wants sewer gas complaints, siphoned traps, or cross-connection violations. Master these terms, and your DWV systems stay clean and code-tight.

PSAM edge: We stock comprehensive pipe and fittings, trap primers, AAVs where code allows, and include compatibility charts to align with system materials and local requirements. Our expert staff will cross-check your spec before you buy.

Mateo once chased a smell complaint to a dry trap in a low-use lab sink. A primer kit fixed it permanently.
Trap and Vent Essentials P-Trap: Water seal that blocks sewer gas; correct depth and venting prevent siphoning. Trap Primer: Device that keeps infrequently used traps from drying out. Cleanout: Access point for rodding/jetting; correct placement saves hours on blockages. Air Gap: Physical separation preventing backflow contamination; mandatory in many fixtures. Wet Vent: Vent shared with a drain; code-specific sizing and distances matter greatly. Installation Accuracy Keep trap weir within code distances from vents. Ensure air gap height complies with fixture standards.
Key takeaway: Venting is a science. PSAM helps you select primers, vents, and fittings that pass inspection and keep systems quiet and safe.
#4. Corrosion & Material Protection – Dielectric and Anode Fundamentals That Extend Lifespan
Corrosion is relentless, especially in mixed-metal systems. Understand isolation and anodes to avoid pinholes, seized unions, and tank failures.

PSAM advantage: Full lineup of dielectric fittings, approved anodes, and replacement parts with manufacturer warranties from professional brands—so you prevent hidden corrosion issues that explode costs later.

Mateo beat a chronic corrosion issue on a copper-to-steel connection by installing the correct isolators and verifying water chemistry.
Dielectric Isolation and Corrosion Dielectric Union: Union that isolates dissimilar metals; stops galvanic current. Dielectric Nipple: Nipple with internal lining to reduce galvanic action. Galvanic Corrosion: Electrochemical reaction between dissimilar metals in electrolyte (water). Anode Rod: Sacrificial metal rod inside heaters that corrodes first, protecting the tank. Use correct thread sealants compatible with linings to maintain isolation. Inspection Practices Check anode rods annually in commercial service; replace before depleted. Look for white/green blooms on unions—classic galvanic indicators.
Key takeaway: Material pairing matters. PSAM stocks the right isolation and anodes, backed by tech guidance to outsmart corrosion long-term.
#5. Backflow & Water Hammer Control – Check Valves, RPZs, and Arrestors That Safeguard Systems
Spikes and backflow events quietly wreck valves, meters, and appliances. Design proper protection, and you keep systems safe, quiet, and compliant.

PSAM supports full assemblies, test kits, and sizing advice from licensed pros, plus job site coordination for larger installs.

Mateo ended a complaint of banging lines by combining water hammer arrestors with pressure control and fixture flow balancing. The building stayed silent.
Flow Protection Devices Water Hammer Arrestor: Absorbs shock waves from fast-closing valves; size to fixture units. Check Valve: One-way flow control; choose spring-checks for hydronic zones to prevent ghost flow. Backflow Preventer: Prevents reverse contamination; choose correct type for hazard level. Double Check Assembly: Medium hazard protection; often for fire lines and irrigation. RPZ (Reduced Pressure Zone Assembly): High hazard protection; requires periodic testing and drainage. Competitor Comparison: PSAM vs. Ferguson (Access, Depth, Service Value)
Regional counter restrictions can complicate purchases, especially when you’re a capable homeowner or a small shop without the “right” account structure. Some traditional houses keep inventories segmented by region, so a part in one branch doesn’t help you across state lines. That leads to waits, workarounds, and wasted time. PSAM solves this with a unified multi-warehouse distribution model and transparent real-time inventory—you see what’s in stock across the network and get it from the closest location.

On quality and support, high-stakes devices like RPZs should never be sold without guidance on sizing, test intervals, and drain capacity. PSAM’s licensed technical support answers those questions, provides installation guides, and ensures assemblies are code-aligned. We also handle same-day shipping on stocked SKUs so you’re not idling crews.

When you roll in faster availability, wholesale pricing, and no-nonsense support, your project risk drops and your labor efficiency climbs—worth every penny.
Testing & Maintenance Maintain test schedules on DC/RPZ devices as required by code. Verify downstream drain capacity for RPZ relief discharge.
Key takeaway: Backflow and hammer control aren’t guesswork. PSAM brings the parts and the proof so you pass tests and avoid damage.
#6. Pressure & Temperature Protection – Expansion, Relief, and Vacuum Devices That Prevent Failures
Water expands. Pressures spike. Relief and containment equipment keep fixtures and tanks safe. If you’ve ever replaced a ballooned heater, you get it.

PSAM provides complete kits—expansion tanks, PRVs, relief valves—and the charts to set pressures properly. Our free shipping on $150+ orders helps keep retrofits profitable.

Mateo eliminated nuisance T&P drips by right-sizing the expansion tank and setting the PRV (pressure-reducing valve) with a calibrated gauge.
Key Protection Components Expansion Tank: Absorbs thermal expansion in closed systems; size to heater volume and pressure. Thermal Expansion: Volume increase as water heats; the reason expansion tanks exist. PRV (Pressure-Reducing Valve): Reduces incoming high pressure to safe levels; protects fixtures. Pressure Relief Valve: Opens when pressure exceeds setpoint; last line of defense. Vacuum Breaker: Prevents back-siphonage; critical on hose bibbs and certain fixtures. Set-and-Forget Done Right Pre-charge expansion tanks to match static pressure. Set PRVs with reference gauges, not guesswork.
Key takeaway: Protect your systems with correct sizing and setpoints. PSAM will match tank models to actual duty and ship the exact spec—no substitutions.
#7. Joining Methods & Fittings – Press, Sweat, and PEX Systems That Prevent Leaks and Callbacks
Your connections are your signature. Pick the right method for environment, access, and temperature—and you’ll leave zero-drip installs with confidence.

PSAM carries press, sweat, and push-to-connect systems from professional brands with the tools to back them up—plus Ridgid and Milwaukee Tools for reliable pressing and cutting. We supply everything from copper pipe to manifolds with a strict no-substitution policy.

Mateo standardized on Viega ProPress for school retrofits where torch use was restricted, cutting hours on tie-ins.
Copper and PEX Essentials ProPress: Press-fitting system for copper; fast, flame-free, and reliable when installed to spec. Sweat Fitting: Traditional soldered joint; durable and proven when cleaned and fluxed properly. PEX-A Expansion: Uses expansion sleeves; excellent for cold climates and full-bore fittings. PEX-B Crimp: Common and cost-effective; ensure correct crimp ring sizing and go/no-go verification. SharkBite (Push-to-Connect): Great for rapid repairs; use with manufacturer-declared temperature/pressure limits. Brazing & Prep Clean, flux, and ream pipe ends. Poor prep ruins perfect materials. In hydronic applications, purge thoroughly and use oxygen-barrier PEX as required.
Key takeaway: Choose joining that fits the job and code limits. PSAM stocks the fittings, tools, and gauges you trust, with 24/7 online ordering so you’re never waiting on counter hours.
#8. Hydronic Heating Components – Circulators, Zones, and Air Elimination That Quiet Systems and Save Energy
Hot water distribution lives or dies on circulator selection, zoning strategy, and air removal. Get those right, and comfort becomes stable and efficient.

PSAM carries professional hydronic lines like Taco, Grundfos, manifolds, separators, and controls, with cross-trade help to integrate with boilers and water heaters from brands like Bradford White and Navien.

On Mateo’s classroom loops, switching to ECM motors slashed electrical costs and tightened ΔT across zones.
Core Hydronic Terms Circulator: Pump that moves water through zones; match to head and GPM. ECM Motor: Electronically commutated motor; variable speed, high efficiency. Zone Valve: Directs flow to zones; pair valve Cv to required GPM. Air Separator: Removes microbubbles; critical for quiet, efficient operation. Manifold: Distributes flow; simplifies balancing and service. Competitor Comparison: PSAM vs. Amazon (Authenticity, Packaging, Warranty)
Hydronic installs can’t tolerate knockoff parts. The market is flooded with non-OEM valves, mislabeled pumps, and accessories that arrive in dented boxes with torn seals. On general marketplaces, you often don’t know how long a pump sat in an uncontrolled warehouse, whether it’s gray-market stock, or if the warranty will be honored. I’ve seen “brand-new” pumps show evidence of a wet end already spun up—and fail within weeks.

PSAM sources directly from manufacturers, tracks lot numbers, and ships from climate-controlled facilities. Pumps and expansion tanks are packaged correctly to survive transit—no mashed flanges or dinged housings. And because our manufacturer warranties are verifiable, we handle issues fast if something arrives damaged. Add same-day shipping on in-stock items and actual technical support for curve selection, and your hydronic projects stop being a dice roll.

Yes, sometimes marketplaces look cheaper. After a callback, wasted labor, and a denied warranty, they’re not. With PSAM, you buy once—worth every penny.
Air-Free Startup Purge each loop individually; use a high-point air vent and separator. Verify ΔT and adjust circulator speed for design targets.
Key takeaway: In hydronics, details pay dividends. PSAM equips you with the right pumps, valves, and know-how for quiet, efficient systems.
#9. Refrigeration Side Essentials – Line Sets, TXVs, and Micron-Level Vacuum That Protect Compressors
Refrigerant circuits reward discipline: clean brazes, nitrogen purges, proper superheat/subcooling, and tight vacuums. Cut a corner, and compressors pay the price.

PSAM stocks line sets, filter driers, TXVs, micron gauges, and high-performance vacuum pumps, delivering the full kit for reliable installs and diagnostics.

Mateo knocked hours off a rooftop swap by ordering preinsulated line sets, a recovery tank, and proper flares with our kit builder.
Critical AC/Refrigeration Terms Line Set: Preinsulated suction/liquid tubing; size to manufacturer specs for capacity and distance. TXV (Thermostatic Expansion Valve): Regulates refrigerant into the evaporator; match tonnage and charge. Superheat: Suction line temp above saturation; verify to protect the compressor. Subcooling: Liquid line temp below saturation; ensures solid column to the metering device. Micron Gauge: Measures vacuum quality; target deep vacuum (e.g., 300–500 microns) with decay test. Brazing and Evacuation Integrity Always nitrogen purge while brazing to prevent scale. Replace driers after opening the system; moisture and acids kill compressors.
Key takeaway: Precision on the refrigeration side prevents big-dollar failures. PSAM gets you the instruments, fittings, and data you need, fast.
#10. Water Heater Essentials – Protection, Efficiency, and Recirculation That Keep Hot Water Reliable
From commercial kitchens to residential master baths, water heater performance hinges on safety devices, efficiency specs, and circulation strategy.

PSAM carries Bradford White tanks, Navien tankless, mixing valves, and recirc pumps from Myers Pumps, with controls and expansion solutions so you order once and finish the whole job.

Mateo replaced a string of nuisance scald complaints by installing a high-quality mixing valve and balancing a dedicated recirc line. Problem solved, no callbacks.
Key Water Heater Terms UEF (Uniform Energy Factor): Standard efficiency rating for water heaters; higher is better. T&P Valve: Temperature and pressure safety valve; must be piped to a safe drain per code. Dip Tube: Directs incoming cold to tank bottom; damaged tubes cause quick temp drop at fixtures. Recirc Line: Hot water return loop; reduces wait times, balances with check valves/flow restrictors. Tempering Valve: Mixing valve that blends hot and cold to prevent scalding and extend capacity. System Integration Size recirc pumps to line length and desired ΔT; consider timer/thermostatic controls for efficiency. Confirm expansion control to protect T&P from nuisance discharge.
Key takeaway: Reliable hot water is engineered, not improvised. PSAM gives you proven heaters, valves, and pumps with the documentation to pass inspection and perform.
FAQ: Your Supply House Questions Answered 1) What’s the difference between a professional supply house and big box stores like Home Depot?
Professional supply houses like PSAM focus on contractor-grade components, deep inventory breadth, and licensed technical support. That means you’ll find press fittings, hydronic components, circulators, backflow assemblies, and commercial valves you won’t see on most retail shelves. Big box stores emphasize consumer-grade goods and seasonal stock, which can leave you short on critical items mid-project. For example, your odds of finding a correctly sized expansion tank, an RPZ with documentation, or a coil-matched TXV are far higher at PSAM. We also provide installation guides, compatibility charts, and real-time inventory so you know what’s available before driving. If you value time, code compliance, and fewer callbacks, a pro supply house is the smart play.
2) Can homeowners buy from professional supply houses or are they contractor-only?
Capable homeowners can absolutely buy from PSAM without a license. While some traditional houses restrict access, PSAM offers wholesale pricing directly to customers and the same professional-grade gear used by licensed trades. If you’re replacing a water heater, fixing a PRV, or upgrading a sump pump, we’ll help you select compatible components, share install documentation, and ensure you get the correct fittings the first time. You get the quality the pros use, without gatekeeping.
3) How does PSAM’s pricing compare to Home Depot, Ferguson, and online retailers?
PSAM typically saves customers 20–40% versus big box retail while delivering equal or better brands. Compared to some traditional houses, we eliminate account barriers and minimums, pairing wholesale pricing with free shipping on $150+ orders. Against generic online marketplaces, we win on authenticity, proper packaging, and responsive warranty support. Add same-day shipping for in-stock orders and you’re not just saving on materials—you’re saving billable hours. Total ownership cost is where PSAM shines.
4) What makes contractor-grade materials superior to consumer-grade products?
Contractor-grade means higher pressure/temperature ratings, tighter manufacturing tolerances, and proven longevity. Think full-port ball valves with robust seals, press fittings with durable o-rings, and ECM circulators with precise controls. In consumer aisles, you’ll often find reduced-port valves, thin-wall fittings, or low-grade elastomers that fail under cycling or high temps. The difference shows up as leaks, noises, and callbacks. PSAM prioritizes professional brands engineered for real-world duty cycles.
5) How can I verify I’m getting authentic products and not counterfeits?
Buy from a supply house with direct manufacturer relationships. PSAM ships from owned warehouses, tracks lot numbers, honors manufacturer warranties, and rejects gray-market stock. With general online sellers, you can encounter repackaged or stored-hot components (especially risky for pumps and electronics). If warranty support matters, authenticity is non-negotiable—another reason to keep your supply lines professional.
6) Do professional supply houses carry better brands than big box stores?
Yes. PSAM features brands like Bradford White, Taco, Grundfos, Myers Pumps, Milwaukee Tools, Ridgid, and Navien—the same names contractors spec daily. In big box aisles, you’ll see a narrower selection oriented to DIY price points and seasonal rotation. For specialized needs—press systems, hydronics, boilers, mixing valves—professional houses have both the variety and the expertise to match applications.
7) What kind of technical support can I expect from a professional supply house?
With PSAM, you get licensed experts who’ve brazed copper, balanced hydronic loops, and sized pumps in the field. We help with fixture counts for water hammer arrestors, TN/TP troubleshooting on heaters, circulator curve matching, and backflow selection. We also provide installation guides and recommend best practices tailored to your system. This isn’t generic advice—it’s job-ready guidance that prevents rework.
8) How quickly can I get parts compared to ordering online or visiting retail stores?
Order in-stock parts before 1 PM and PSAM processes the order the same day from the nearest warehouse. Compared to online marketplaces that rely on third-party drop shippers (7–14 days is common), PSAM’s multi-warehouse distribution is faster and more predictable. When retail shelves are empty on seasonal items, PSAM tends to have steady supply. Speed plus certainty equals more billable hours and fewer dead stops.
9) Do I need a contractor license or special account to buy from PSAM?
No license required. You can check out as you need or set up a pro account for volume discounts, job site coordination, purchase tracking, and dedicated support. Pros love consolidating orders by job and sharing carts with techs in the field. Homeowners appreciate wholesale access and expert guidance.
10) What are the benefits of setting up a pro account vs. Ordering as needed?
A pro account unlocks volume pricing, net terms (on approval), saved carts, and fast reorders from your purchase history. You’ll also get dedicated account management, better freight coordination for large equipment, and priority on emergency support. For teams, it standardizes what gets installed—reducing variability and increasing first-time fix rates.
11) How can a supply house help me avoid buying wrong parts or incompatible components?
PSAM pairs parts validation with compatibility charts, and our techs sanity-check specs against your real-world conditions—pipe sizes, material types, pressure/temperature ratings. Whether it’s press jaws for a specific fitting profile or an RPZ sized for fixture units, we make sure your cart is right. That means fewer returns, fewer change orders, and fewer headaches.
12) What should I look for when choosing between multiple supply house options?
Look for: inventory depth across trades (plumbing, HVAC equipment, hydronic heating), transparent real-time inventory, same-day shipping, access for both pros and capable homeowners, licensed technical support, and a strict no-substitution policy. If a house can’t guarantee authenticity or guide you on sizing and code, you’re gambling with your schedule and reputation. PSAM checks all those boxes—consistently.
Conclusion: Turn Terms into Profits with PSAM’s Pro-Grade Support
A glossary is just words until it changes what you buy and how you build. Now you’ve got 50 high-impact terms across hydraulics, drainage, protection, joining, hydronics, refrigeration, and water heating—exactly what it takes to spec with confidence and finish without callbacks. This is where Plumbing Supply And More (PSAM) stands apart: 20,000+ professional-grade products, same-day shipping from a multi-warehouse distribution network, true wholesale pricing, and licensed technical support that’s walked the same job sites you have.

Mateo Abarca’s Albuquerque project is proof. After burning hours on the wrong fittings and a counterfeit valve, he switched to PSAM, closed his loop issues, and cut downtime to near zero. That’s the real power of pairing field knowledge with a supply partner that delivers—on parts, documentation, and speed. When reliable sourcing meets sharp terminology, jobs run smoother, margins go up, and customers stay loyal.

Ready to eliminate guesswork? Build your next cart with PSAM. You’ll get exactly what you specified—no substitutions, no surprises, and solutions that are, every time, worth every penny.
Quick Reference: The 50 Terms Covered
1) Static Pressure 2) Dynamic Pressure 3) Head (Feet of Head) 4) PSI 5) GPM 6) Cv 7) FPS Velocity 8) Friction Loss 9) ΔP 10) Water Column (in. WC) 11) P-Trap 12) Trap Primer 13) Cleanout 14) Air Gap 15) Wet Vent 16) Dielectric Union 17) Dielectric Nipple 18) Galvanic Corrosion 19) Anode Rod 20) (Material Isolation Concept) 21) Water Hammer Arrestor 22) Check Valve 23) Backflow Preventer 24) Double Check Assembly 25) RPZ 26) Expansion Tank 27) Thermal Expansion 28) PRV 29) Pressure Relief Valve 30) Vacuum Breaker 31) ProPress 32) PEX-A Expansion 33) PEX-B Crimp 34) Sweat Fitting 35) SharkBite (Push-to-Connect) 36) Circulator 37) ECM Motor 38) Zone Valve 39) Air Separator 40) Manifold 41) Line Set 42) TXV 43) Superheat 44) Subcooling 45) Micron Gauge 46) UEF 47) T&P Valve 48) Dip Tube 49) Recirc Line 50) Tempering Valve

Note: For term 20, we discussed the concept of material isolation holistically as “Dielectric Isolation,” reinforcing 16–17.