16 Va. Admin. Code § 25-50-440

Current through Register Vol. 41, No. 8, December 2, 2024

Section 16VAC25-50-440 - Automatic low-water fuel cutoff and/or water-feeding device

A. Each automatically fired and unattended steam or vapor system boiler, except miniature boilers, shall be equipped with at least two automatic low-water fuel cutoffs located so as to cut off the fuel or energy supply automatically when the surface of the water falls to the lowest safe water line. Functioning of the lower of the two controls shall cause safety shutdown and lockout. The manual reset may be incorporated in the lower cutoff control. If a water-feeding device is installed, it shall be constructed so that the water inlet valves cannot feed water into the boiler through the float chamber and located so as to supply requisite feedwater. The lowest safe water line should be not lower than the lowest visible part of the water glass.

B. The fuel cutoff or water feeding device shall be attached directly to a boiler or in the tapped openings available for attaching a water glass directly to a boiler, provided the connections are made to the boiler with nonferrous tees or Y's not less than 1/2-inch pipe size between the boiler and the water glass so that the water glass is attached directly and as close as possible to the boiler; the run of the tee or Y shall take the water glass fittings, and the side outlet or branch of the tee or Y shall take the fuel cutoff or water feeding device. The ends of all nipples shall be reamed to full-size diameter.

C. Fuel cutoffs and water feeding devices embodying a separate chamber shall have a vertical drain pipe and a blowoff valve not less than 3/4-inch pipe size, located at the lowest point in the water equalizing pipe connections so that the chamber and the equalizing pipe can be flushed and the device tested.

D. A forced circulation coil or water tube type boiler, with a heat input greater than 400,000 BTU's per hour shall have a flow sensing device installed to cut off the fuel supply at a minimum water circulation flow rate in the boiler. The boiler manufacturer's specifications for the safe minimum flow rate, setting, and location of the flow sensing device shall be utilized.

16 Va. Admin. Code § 25-50-440

Derived from VR425-01-75 § 4.6, eff. July 1, 1974; amended, eff. November 1, 1978; July 1, 1991; September 1, 1993; Virginia Register Volume 15, Issue 5, eff. January 1, 1999; Volume 19, Issue 19, eff. July 2, 2003.

Statutory Authority

§ 40.1-51.6 of the Code of Virginia.