초록 ▼

A tankless electric water heater having instantaneous hot water output includes an open-ended folded tubular conduit having a separate metal-sheathed immersion heating element inserted in to each end of the conduit and carried by a cap member sealing the open end. Each cap member carries a thermosta

A tankless electric water heater having instantaneous hot water output includes an open-ended folded tubular conduit having a separate metal-sheathed immersion heating element inserted in to each end of the conduit and carried by a cap member sealing the open end. Each cap member carries a thermostat having a preset temperature of about 140°F. and connected in series with the heating element carried by the respective cap member. A self-regulating PTC heating cable, either disposed in or wrapped around the tubular conduit, is continuously energized independently of the metal-sheathed heating elements to maintain the water in the tubular conduit a constant temperature of about 150°C. during standby periods. A water inlet conduit connected to one cap member is provides with a water flow responsive switch connected in series with the thermostastic for energizing the metal-sheathed heating elements upon demand for hot water flow and hot water is discharged through an outlet conduit connected to the other cap member.

대표청구항 ▼

A tankless water heater having instantaneous hot water output and comprising: a. an open ended hollow insulated housing fitted with a folded tubular conduit, having a separate metal-sheathed electrical resistance heating element inserted into each end of the tubular conduit, and a cap member sealed

A tankless water heater having instantaneous hot water output and comprising: a. an open ended hollow insulated housing fitted with a folded tubular conduit, having a separate metal-sheathed electrical resistance heating element inserted into each end of the tubular conduit, and a cap member sealed to each end of the tubular conduit and serving to mount the first and second heating elements therein; b. a water inlet conduit joined to a first cap member, and a water outlet conduit joined to the other cap member; c. a temperature-sensing thermostat mounted in each cap member, and having a preset temperature of about 140°F., and connected in series with the adjacent heating element mounted on the respective cap member, and a water flow meter mounted in the water inlet conduit and in series with each thermostat; d. a third, continuously energized independently of said metal-sheathed heating elements, self-regulating PTC heating cable in heat exchange relationship with the folded tubular conduit, for maintaining the water temperature therein at a predetermined temperature at about 150°F., whereby the electrical resistance of this heating cable increases as the temperature increases, and the heat output drops to a level that is just enough to replenish the heat losses, and maintain the water within the folded conduit at a temperature of about 150°F., so that the water heater will always supply hot water, when water is caused to flow from the water outlet conduit.