Kunkle Valve 0537-H01-HM0060 Relief Valve

The Kunkle Valve 0537-H01-HM0060 is a heavy-duty ASME Section IV steam relief valve designed specifically for low-pressure hot water boilers, heat exchangers, and steam generators. This 2" NPT inlet x 2-1/2" NPT outlet valve is National Board certified ("HV" designator) and comes factory-set at 60 PSI to handle a high discharge capacity of 10,525 lb/h (PPH) or 10,524,997 BTU/h. Engineered for durability in demanding HVACR environments, it features a B584 alloy 84400 bronze seat and a resilient EPDM insert that ensures a tight seal and reliable pop-action. The stainless steel spring (A313-631) and top-guided disc assembly are protected by an isolating diaphragm, preventing corrosion of internal working parts from discharged media. A heavy-duty lift lever transitions easily for manual testing, while the pivot design between the disc and spring compensates for side thrust, maintaining precise alignment during critical overpressure events.

• Dual Protection: Expertly handles overpressure from both thermal expansion and over-firing due to control failures.
• Corrosion Resistance: Incorporates a specialized diaphragm to keep discharge liquid away from the spring and guide.
• High-Capacity Flow: Rated for over 10 million BTU/h, making it suitable for large-scale commercial boiler systems.
• Rugged Construction: Utilizes an extra-heavy bronze seat and stainless steel trim for long-term service life in high-temperature applications up to 250°F.
• Precision Seating: Detailed top-guided design and resilient seals provide consistent performance and minimize simmer.

What is the difference between an ASME Section IV and Section VIII valve?
Section IV valves, like the Kunkle 537, are specifically coded for low-pressure heating boilers (steam or hot water), whereas Section VIII valves are intended for unfired pressure vessels. Always verify your local boiler codes to ensure the "HV" designator is appropriate for your installation.

Can this valve be mounted horizontally?
No. To maintain National Board certification and proper mechanical function, this boiler safety relief valve must be installed in a vertical position with the spindle upright. Horizontal mounting can lead to debris accumulation and interference with the disc’s lift.

Why is there a small hole in the valve body?
This is a factory drain hole required by ASME code. It prevents condensate from pooling above the seat, which could cause corrosion or freeze and jam the valve. Ensure this is piped to a safe discharge location according to mechanical codes.

This item is not eligible for free shipping.

Disclaimer: While we strive for 100% accuracy, product data and specifications are subject to change. Please contact our team to confirm compatibility or technical details before purchasing.