Two-stage water heater assembly

Abstract

A two stage water heater assembly comprising a tankless stage, which preheats water, and water storage tank stage, which stores the preheated water and maintains the water at a desire temperature. This water heater assembly provides the user with an unlimited supply of hot water on demand while doing so in a more energy efficient manner than either an inline tankless water heater or a traditional tank-type water heater.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic view of the apparatus of the invention.

FIG. 2 is a perspective view of the apparatus of the invention.

FIG. 3 is a top view of the tankless stage of the apparatus of the present invention.

DETAILED DESCRIPTION OF THE INVENTION

FIG. 1 illustrates a two stage water heater assembly 1, comprising a tankless stage 2 and a storage stage 3. Water 4 enters the tankless stage through cold water inlet 5. The water 4 circulates through entrance chamber 6 through coiled tubing 7 and is heated by a first heating means 8. In FIG. 1, a natural gas burner is used as the heating means although the heating means could also include a propane burner, a heating oil burner or electric heating elements. Heating means 8 is connected to control valve 9. Exhaust gas from heating means 8 is vented to the atmosphere through exhaust flue 24. After being heated by heating means 8, pre-heated water 14 exits tankless stage 2 through hot water outlet 10. Pre-heated water 14 then enters storage stage 3 through hot water inlet port 11, which is connected to flow control valve 12. Pre-heated water 14 is stored in water storage tank 13 until it is desired for use. Pre-heated water 14 is maintained at a desired temperature by second heating means 15, which is located beneath lower wall 17 and connected to control valve 16. Exhaust from heating means 15 is vented to the atmosphere through exhaust flue 18. Heated water 19 exits storage stage 3 for use by the user through hot water outlet 20, which is activated by hot water flow control valve 21. Temperature sensing means 22 and tank water level sensing means 23 are located within storage tank 13. Temperature sensing means 22 is connected to control valve 16, which activates heating means 15 when temperature sensing means 22 indicates that the temperature of pre-heated water 14 in storage tank 13 is below a temperature selected by the user. Tank water level sensing means 23 is connected to flow control valve 12, which activates hot water inlet port 11 when tank water level sensing means 23 indicates that pre-heated water 14 has dropped below a certain level within storage tank 13. Flow control valve 12 is connected to control valve 9. When flow control valve 12 activates hot water inlet port 11, it also sends a signal to control valve 9, which in turn activates heating means 8, which heats water 4 flowing through coiled tubing 7.

When the user desires hot water and turns on a hot water tap, control valve 21 is activated and opens hot water outlet 20 permitting hot water 19 to flow through pipes to the user. This will result in a drop in the water level within storage tank 13 causing tank water level sensing means 23 to send a signal to flow control valve 12, which then permits pre-heated water 14 to enter storage tank 13 through hot water inlet port 11.

The assembly is approximately the same size as traditional tank-type water heater, which is predominantly used in the U.S., so it can easily fit into the space that was previously occupied by a traditional tank-type water heater. Thus, it provides a cheaper, more efficient, more reliable option to either an inline tankless water heater or a traditional tank-type water heater.

The description of the invention above should not be interpreted as limiting the invention to the disclosed embodiment because those who are skilled in the art to which the invention relates will be able to devise other equivalent forms thereof within the scope of the invention. Variations and changes, which are obvious to one skilled in the art, are intended to be within the scope and nature of the present invention.

Claims

1. A two-stage water heater assembly comprising: a tankless stage comprising an entrance chamber with an elongated, coiled tube located within said entrance chamber, said tube connected in fluid receiving relation to a cold water inlet and located above first heating means, said first heating means are adapted for heating water that flows through said tube, said water being allowed to exit the tankless stage through a hot water outlet;a storage stage comprising an upright thermally insulated cylindrical water storage tank with a hot water inlet port connected in fluid receiving relation to the hot water outlet of said tankless stage and attached to a flow control valve, second heating means for heating the water within the storage tank, temperature sensing means for said water storage tank, said temperature sensing means producing a signal indicative of the water temperature in said water storage tank, tank water level sensing means, said tank water level sensing means producing a signal indicative of the water level in said water storage tank, said water being allowed to exit the storage stage through a second hot water outlet; andcontrol means connected to said flow control valve and responsive to the signals produced by said tank water level sensing means to maintain the water stored in the water storage tank at a certain level by activating the hot water inlet port only if the tank water level sensing means indicate that the water is below the required water level; andcontrol means connected to said second heating means and responsive to the signals produced by said temperature sensing means to maintain the water stored in the water storage tank and released through said second hot water outlet at a desired temperature by activating the heating element in the storage stage only if the water temperature sensing means indicate that the water is below the desired outlet temperature as selected by an outlet temperature selecting means.

2. The two stage water heater assembly of claim 1 wherein the heating means is electrical.

3. The two stage water heater assembly of claim 1 wherein the heating means is natural gas.