US8276548B2 - Low Cost Tankless Portable Water Heater - Google Patents

5 to 10 gallons of scorching water with recovery occasions starting from 30 to 60 minutes. Burner apparatus together with a burner, is disposed in an operative relationship with the heat exchanger for heating water flowing by means of the heat exchanger. An electronic direct spark ignition board and a Gas Regulator with an robotically controlled Dual Solenoid shut-off valve are supplied for operating the burner apparatus in accordance with the requirements of the ANSI Z21.10.3 security standard. BTU ranges at totally different water circulate rates. This characteristic is achieved using a low price metallic disc thermostat to instantly activate the Dual BTU valve with out the need of an costly microprocessor management. It is a necessary safety characteristic often referred to as a Limit Switch. A further safety function is achieved by incorporating a Relay and a steel disc thermostat on the exhaust housing that cause the induced draft blower to remain working after each burn till the exhaust housing reaches a low temperature, thus eliminating thermal stress on the heat exchanger and exhaust parts.



FIG. Three is a perspective view of the heater proven in FIGS. FIG. 4 is one other perspective view of the heater shown in FIGS. FIG. 5 is a functional diagram of the heater shown in FIGS. 10 in accordance with the present invention features a sealed housing 14 , fabricated from any appropriate material equivalent to metallic, which includes an air inlet 18 and a flue outlet 22 . 26 includes a plenum 30 with surround tubing 34 connected to a cold-water inlet 36 and a scorching water outlet 38 . As proven in FIG. 2 , the cold-water inlet 36 and sizzling water outlet 38 lengthen outdoors of the sealed housing 14 . Burner apparatus forty two includes a burner 44 which is disposed in an operative relationship with the heat exchanger 26 for heating water flowing through the tubing 34 . Seventy four also displays the flame of the burner forty four verifying the presence of ionization at the location of a spark igniter 76 and promptly shuts off the gasoline circulate via the dual solenoid valves fifty four .



44 , regulator 48 , and solenoid valves fifty four are typical and are available from several domestic and foreign suppliers for use in conventional gasoline appliances. BZB02A0502 with Dual BTU choice. An exhaust system fifty eight together with a blower 60 with blower motor sixty two , blower relay sixty four , ignition relay 66 , and time delay swap 68 (See FIG. 5 ), is supplied for inducing draft of air from the air inlet 18 through the heat exchanger 26 and out of the flue outlet 22 . This enormously enhances the effectivity of the burner 44 heat exchanger 26 , and as hereinbefore famous, provides the performance benefits relating to condensation supplies stressing and wind resistance. 74 with a spark igniter 76 which could also be of any accredited conventional design certified by an appropriate company (i.e. CSA, UL or different), is provided for operating the burner apparatus forty two and the exhaust system fifty eight .



80 is provided in the hot water line to offer pressure relief in case of overheating in the new water line 38 in a traditional manner. Eighty four is disposed in the outlet scorching water line 38 and a solenoid valve 86 , related to each the anti-freeze thermostat switch 84 and outlet sizzling water line 38 , small space heater offers for drawing water from the hot water outlet line 38 upon receipt of the sign from the anti-freeze thermostatic switch which is configured for offering a signal at a preselected temperature. Such anti-freezing thermostatic switches are available from Thermo-Disc, Klixon, Cantherm and different accepted suppliers. 86 is disposed outdoors the housing 14 and diverts water by a drain line 90 to the atmosphere or to a recycle tank (not proven). 90 to the atmosphere or to a recycle tank (not proven). 94 interconnected with the ignition board for igniting the burner forty four and heating water to a selected temperature at which the temperature freeze switch closes the solenoid valve.



98 could also be disposed in the outlet sizzling water line 36 and is interconnected with the ignition board and the solenoid valves 54 to control the burner operation to a decrease of the two BTU levels at a selected water temperature, for example 45° C. At this temperature, the burner at a lower BTU supplied reduced water heating to keep up a desirable output water temperature in the recent water outlet 38 and faucet 102 . "flow switch" 94 which, in flip, activates the "ignition relay" 66 that applies power to the system. After a successful ignition, the system will instantly start supplying hot water. At regular (less than 60 F) the output water temperature starts rising significantly at any time when the movement is diminished to below 1 gal/min. This isn't unusual in an RV where the water supply could also be small space heater when "dry camping" utilizing a storage tank. If the temperature exceeds one hundred twenty F the t-mod change 98 opens; this causes the twin BTU valve to reduce the fuel stream and the water temperature decreases.