Safety valve for hot water heater

A shutoff valve (10) for use with a container (62), the shutoff valve (10) comprising:

• a housing (12, 14) having an inlet (34) operatively connected to a source of pressurized fluid (64B) and an outlet (36) operatively connected to the container (62), the outlet (36) having a valve seat (24);
• a valve member (26) moveable to a first position in which the valve member (26) sealingly engages the valve seat (24) to prevent a flow of fluid through the outlet (36), the valve member (26) further moveable to a second position in which the valve member (26) disengages the valve seat (24) to allow a flow of fluid through the outlet (36);
• a bias spring (54) urging the valve member (26) to the first position;
• a piston (18) operatively attached to the valve member (26), the piston (18) being disposed in a chamber (20), the chamber (20) being in fluid communication with the outlet (36) such that the pressure in chamber (20) is equal to the pressure in outlet (36), the piston (18) operating to oppose the bias spring (54) such that pressure in chamber (20) produces a force that urges valve member (26) to the second position, whereby falling pressure in outlet (36) causes the pressure in chamber (20) to fall by an equal amount thereby allowing bias spring (54) to overcome the force urging valve member (26) to the second position, thus allowing valve member (26) to move to the first position, preventing the flow of fluid through the outlet (36) into container (62);
• and
• a reset lever (32) operably attached to the valve member (26), the reset lever (32) being movable to an engaged position, in which the reset lever (32) moves the valve member (26) to the second position, the reset lever (32) further movable to a disengaged position in which the reset lever (32) allows the valve member (26) to be moved to the first position.