3421AB LF Tankless Water Heater Valve Kit
Engineered specifically for hot-side operation (red handle), this heavy-duty valve delivers reliable performance with:
✔ Lead-free brass construction (NSF/ANSI/CAN 61 & 372 certified)
✔ 600# WOG rating for water, oil, or gas service (non-shock)
✔ Full-port design – Maximizes flow with minimal pressure drop
Key Features
✅ Hot Water Optimized – Red handle ensures correct installation on supply line
✅ Durable Components – Virgin PTFE seats + blow-out proof stem
✅ Easy Maintenance – Integral drain/purge port with protective cap
✅ Safety Ready – 3/4" relief valve port (choose capacity):
- 3420RAB: 200K BTU/hr
- 3420SAB: 500K BTU/hr
- 3420TAB: 2.7M BTU/hr
Technical Highlights:
- ¼-turn operation for quick shutoff
- FNPT x FNPT connections (ASME B1.20.1-NPT compliant)
- Adjustable packing nut – Maintains seal over time
- AB1953 compliant – Safe for potable water systems
Why Installers Choose This Valve
• Trusted Materials: Lead-free brass meets strict plumbing codes
• Proven Design: Withstands high temps in tankless/boiler systems
• Complete Kit: Includes all needed ports (drain + relief valve)
Ideal For:
- Tankless water heater supply lines
- Commercial/residential plumbing
- High-efficiency boiler systems
Order Note: Specify required BTU relief model (RAB/SAB/TAB)
Di m e n s i o n , Weight
| Size | Φ [in] | ΦSC [in] | ΦP [in] | A [in] | B [in] | C [in] | H [in] | Wt.* [lb] |
|---|---|---|---|---|---|---|---|---|
| 3/4" | 3/4 - 14 NPT | 3/4 - 14 NPT | 0.73 | 4.06 | 2.35 | 1.14 | 1.66 | 1.71 / 1.60 |
| 1" | 1 - 11.5 NPT | 3/4 - 14 NPT | 0.98 | 4.34 | 2.54 | 1.35 | 2.11 | 1.92 / 1.80 |
*Weight may vary slightly between models
Material
| Part # | Component | Material Specification |
|---|---|---|
| 1 | Body | Lead Free Brass ASTM B927 C27450 |
| 2 | Fixed end | Lead Free Brass ASTM B927 C27450 |
| 3 | Ball | Lead Free Brass / Cr plated ASTM B927 C27450 |
| 4 | Seat | PTFE PTFE |
| 5 | Stem | Lead Free Brass ASTM B927 C27450 |
| 6 | Packing ring | PTFE PTFE |
| 7 | Packing nut | Brass ASTM B124 C37700 |
| 8 | T-handle | Aluminum ASTM B85 |
| 9 | Handle nut | Steel /Zn plated ASTM A36 |
| 10 | Handle screw | Steel /Zn plated ASTM A36 |
| 11 | Handle | Aluminum ASTM B85 |
| 12 | Stem | Lead Free Brass ASTM B927 C27450 |
| 13 | Union nut | Brass ASTM B283 C37700 |
| 14 | Union | Lead Free Brass ASTM B927 C27450 |
| 15 | O-ring | EPDM Perox NSF approved |
| 16 | Cap retainer | Rubber - |
| 17 | Drain cap | Brass ASTM B283 C37700 |
| 18 | Drain gasket | EPDM Perox NSF approved |
| 19 | Ball | Lead Free Brass / Cr plated ASTM B927 C27450 |
| 20 | Seat | PTFE PTFE |
| 21 | Fixed end | Lead Free Brass ASTM B927 C27450 |