Women Owned Business Enterprise
RED-WHITE VALVE CORP.  |  SKU: 30078517  |  MPN: 3420LRAB 3/4

3420LAB LF Threaded Tankless Water Heater Valve Kit

$156.31
SIZE & KIT
  • All-Threaded FNPT x FNPT System – Fully threaded, solder-free connections ensure leak-proof integrity in high-pressure water/gas lines, ideal for permanent industrial and commercial installations.
  • 200K/500K BTU Scalable Relief – Versatile overpressure protection for residential to mid-commercial systems, eliminating the need for multiple valve models.
  • Long-Body Durability – Extended design simplifies maintenance in cramped spaces and withstands vibration in outdoor/harsh environments.
  • 600 PSI WOG + AB1953 Compliance – Combines industrial pressure resilience with California lead-free standards for potable water safety.
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Engineered for HVAC professionals and contractors, the 420LAB LF Valve Kit delivers industrial-grade performance with fully threaded FNPT connections and a long-body design for seamless integration into residential and commercial tankless water heater systems. Featuring dual BTU relief options, lead-free construction, and unmatched durability, this kit ensures code-compliant safety and reliability in high-pressure environments.

Key Features & Benefits

✔️ Fully Threaded FNPT x FNPT Connections – Simplified, solder-free installations with ASME B1.20.1-NPT threads for leak-proof water and gas line integrations.
✔️ Dual BTU Relief Capacity – Choose 200K BTU/hr (3420LRAB) for residential systems or 500K BTU/hr (3420LSAB) for commercial applications.
✔️ 600 PSI WOG Industrial Rating – Full-port design with virgin PTFE seats ensures maximum flow and durability in water, oil, or gas systems.
✔️ Long-Body Design – Extra length for easier installation and maintenance in tight spaces or complex plumbing configurations.
✔️ AB1953 & NSF-61/372 Certified – Meets California’s strict lead-free standards and North American potable water safety requirements.

Technical Specifications

  • Connections: 3/4" FNPT x FNPT (ASME B1.20.1-NPT)
  • Relief Valve Options:
    • 3420LRAB: 200K BTU/hr
    • 3420LSAB: 500K BTU/hr
  • Materials: Lead-free brass, PTFE seats
  • Pressure Rating: 600 PSI WOG (non-shock)
  • Operation: ¼-turn with blow-out-proof stem
  • Standards: NSF/ANSI/CAN 61, NSF-372, AB1953

Why Choose This Kit?

  • Threaded System Superiority – Ideal for installations requiring robust, permanent threaded connections without soldering.
  • Scalable Performance – Supports both residential and mid-sized commercial tankless units.
  • Maintenance-Friendly – Integral drain/purge ports and adjustable packing simplify upkeep.
  • Corrosion Resistance – Lead-free brass construction withstands aggressive media and harsh environments.

Ideal Applications

  • High-efficiency residential tankless water heaters
  • Commercial kitchens, laundromats, and multi-unit housing
  • Hydronic heating systems with threaded piping
  • Retrofit projects requiring durable, code-compliant upgrades
  • Outdoor installations exposed to weather or vibration

Built for Professional Reliability

✅ Code-Compliant Design – Exceeds NSF, AB1953, and ASME standards.
✅ Industrial Durability – 600 PSI rating and blow-out-proof stem handle extreme pressures.
✅ Contractor-Approved – Pre-assembled kit reduces installation time by 30%.

Engineered for Longevity – Trusted in systems where threaded integrity and high BTU loads are critical.

All-Threaded | Dual BTU Relief | Lead-Free

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