4BE3.5 U3 C1 Obj 4 Matching

HLW-800.1 = Each water heater shall have at least one officially rated temperature and pressure safety relief valve or at least one officially rated safety relief valve. HLW-801 = These pressure relief valves must be installed not lower than 100 mm from the top of the shell. ASME BPVC IV, Part HLW = Commercial and industrial potable water heaters and hot water storage tanks operate at pressures not exceeding 1100 kPa, and temperatures not exceeding 99°C. ASME BPVC Section IV = Refers to safety relief valve requirements for industrial and commercial potable water heaters.

Water heater = Highest working pressure rating. Valves = May have a lesser working pressure rating than the water heater. Pumps = May have a lesser working pressure rating than the water heater. Expansion or storage tanks = May have a lesser working pressure rating than the water heater.

a) Not lower than 100 mm from the top of the shell = Vertical installation requirement. b) Directly to one of the following: = Connection requirements for the relief valve. c) With their spindles upright and vertical = Directional requirement for the spindles. With no horizontal connecting pipe = Restriction on connecting piping.

<p>Pressure setting = Less than or equal to the maximum allowable working pressure of the water heater. Temperature setting = Not specified in the content. Working pressure rating = Based on the component with the lowest maximum allowable working pressure rating. Valve installation = Not specified in the content.</p> Signup and view all the answers

<p>Temperature and pressure safety relief valves = Protect against the additional explosion dangers associated with super-saturated hot water. Safety relief valves = May be used on commercial and industrial potable water heaters and hot water storage tanks. Expansion or storage tanks = Part of the hot water supply system. Piping = Part of the hot water supply system.</p> Signup and view all the answers

<p>Y-base = Connection requirement for the relief valve. Tapped or flanged opening in the top of the water heater = Connection requirement for the relief valve. Fitting connected to the water heater by a short nipple = Connection requirement for the relief valve. Valveless header connecting water outlets on the same heater = Connection requirement for the relief valve.</p> Signup and view all the answers

<p>Commercial and industrial potable water heaters = Operate at pressures not exceeding 1100 kPa, and temperatures not exceeding 99°C. Hot water storage tanks = Operate at pressures not exceeding 1100 kPa, and temperatures not exceeding 99°C. Safety relief valves = Not specified in the content. Pumps = Not specified in the content.</p> Signup and view all the answers

<p>Valves = Part of the hot water supply system. Pumps = Part of the hot water supply system. Expansion or storage tanks = Part of the hot water supply system. Water heater = Supplies hot potable water.</p> Signup and view all the answers

<p>d) No piping or fitting used to mount the safety relief valve can be of a nominal pipe size smaller than that of the valve inlet. = To ensure proper installation and operation ASME does not prohibit the installation of relief devices sensitive only to temperature. = However, ASME considers these devices to be insufficient for vessel protection The combination temperature and pressure relief valve provides protection for both over-pressurization, and dangerously high water temperatures. = It provides protection against thermal expansion of water and high water temperatures The safety relief valve operates with a pop action when over-pressurization occurs. = It is a characteristic of the safety relief valve</p> Signup and view all the answers

<p>Fusible element = Melts at 99°C, and allows the hot water to escape, but does not reseat Rod and tube arrangement = Opens the device at 99°C, and closes it at 71°C, and automatically recloses T&amp;P valve = Has a wax-filled thermostatic sensor probe that expands against the force of the compression spring, and lifts the valve disc off its seat Compression spring = Holds a disc shut against a seat in a safety relief valve</p> Signup and view all the answers

<p>In this case, the valve may be installed in the horizontal position with the outlet pointed down. = To ensure proper installation and operation Safety relief valves shall not be connected to an internal pipe in the water heater or a cold water feed line connected to the water heater. = To prevent improper installation and operation ASME considers these devices to be insufficient for vessel protection. = Relief devices sensitive only to temperature The combination temperature and pressure relief valve provides protection for both over-pressurization, and dangerously high water temperatures. = It provides protection against thermal expansion of water and high water temperatures</p> Signup and view all the answers

<p>Wax-filled thermostatic sensor probe = Expands against the force of the compression spring, and lifts the valve disc off its seat Compression spring = Holds a disc shut against a seat in a safety relief valve Temperature element = Opens when the water temperature rises to about 99°C Disc = Lifts off its seat when the wax-filled thermostatic sensor probe expands</p> Signup and view all the answers

<p>The pressure element opens to relieve excess pressure, usually caused by thermal expansion of water during times of low hot water consumption. = To prevent over-pressurization The temperature element opens when the water temperature rises to about 99°C. = To prevent overheating The combination temperature and pressure relief valve provides protection for both over-pressurization, and dangerously high water temperatures. = It provides protection against thermal expansion of water and high water temperatures The valve disc lifts off its seat when the wax-filled thermostatic sensor probe expands. = To discharge the overheated water</p> Signup and view all the answers

<p>It is recommended that T&amp;P valves receive annual try lever tests. = To ensure proper operation and maintenance The safety relief valve operates with a pop action when over-pressurization occurs. = It is a characteristic of the safety relief valve The fusible element does not reseat after melting. = It must be replaced after use The rod and tube arrangement automatically recloses after opening. = It is a characteristic of the rod and tube arrangement</p> Signup and view all the answers

<p>Disc = Lifts off its seat when the pressure exceeds a certain level Compression spring = Holds a disc shut against a seat in a safety relief valve Non-adjustable compression spring = Provides the force to hold the disc shut against a seat Seat = Provides a surface for the disc to shut against</p> Signup and view all the answers

<p>Safety relief valve = Operates with a pop action when over-pressurization occurs Temperature and pressure relief valve = Provides protection for both over-pressurization, and dangerously high water temperatures Temperature relief device = Only provides protection against high water temperatures Fusible element = Melts at 99°C, and allows the hot water to escape, but does not reseat</p> Signup and view all the answers