Classifications

• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F24—HEATING; RANGES; VENTILATING
  • F24H—FLUID HEATERS, e.g. WATER OR AIR HEATERS, HAVING HEAT-GENERATING MEANS, e.g. HEAT PUMPS, IN GENERAL
  • F24H1/00—Water heaters, e.g. boilers, continuous-flow heaters or water-storage heaters
  • F24H1/48—Water heaters for central heating incorporating heaters for domestic water
  • F24H1/52—Water heaters for central heating incorporating heaters for domestic water incorporating heat exchangers for domestic water
  • F24H1/523—Heat exchangers for sanitary water directly heated by the burner
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F24—HEATING; RANGES; VENTILATING
  • F24H—FLUID HEATERS, e.g. WATER OR AIR HEATERS, HAVING HEAT-GENERATING MEANS, e.g. HEAT PUMPS, IN GENERAL
  • F24H1/00—Water heaters, e.g. boilers, continuous-flow heaters or water-storage heaters
  • F24H1/48—Water heaters for central heating incorporating heaters for domestic water
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F24—HEATING; RANGES; VENTILATING
  • F24H—FLUID HEATERS, e.g. WATER OR AIR HEATERS, HAVING HEAT-GENERATING MEANS, e.g. HEAT PUMPS, IN GENERAL
  • F24H1/00—Water heaters, e.g. boilers, continuous-flow heaters or water-storage heaters
  • F24H1/48—Water heaters for central heating incorporating heaters for domestic water
  • F24H1/52—Water heaters for central heating incorporating heaters for domestic water incorporating heat exchangers for domestic water

Definitions

• the present invention relates to a gas boiler.
• the present invention relates to a wall-mounted combination gas boiler, i.e. a wall- mounted boiler for supplying both hot water to a heating circuit - hereinafter referred to as heating water - and domestic hot water.
• a wall-mounted combination gas boiler i.e. a wall- mounted boiler for supplying both hot water to a heating circuit - hereinafter referred to as heating water - and domestic hot water.
• a wall-mounted combination gas boiler normally comprises a heating circuit, along which hot heating water is conducted; and a domestic circuit, along which domestic water is conducted.
• the heating circuit is connected to an external heating circuit equipped with radiators; and the domestic circuit is connected at one end to the water mains or other domestic water source, and, at the other end, to a circuit for distributing hot domestic water to one or more user devices.
• a wall-mounted combination gas boiler also comprises a gas burner, and at least one heat exchanger for transferring the heat produced by the burner to the heating water and domestic water.
• a boiler of the above type When hot domestic water is drawn off by a user device, a boiler of the above type operates as follows: on detecting domestic water flow, a flowmeter located along the domestic circuit lights the burner; and the domestic water is heated as it flows through the heat exchanger, and is fed to the user device.
• the wall- mounted gas boiler described above has several drawbacks, by failing to supply the domestic water user device immediately with water at a predetermined temperature . That is, between the water being supplied and reaching a predetermined temperature, there is a transient period during which the domestic water is supplied at gradually increasing temperature until the predetermined temperature is reached.
• Patent EP 719,989 proposes a wall-mounted combination gas boiler equipped with a storage tank, located along the domestic circuit, downstream from the heat exchanger, and with an auxiliary heating device for keeping the domestic water within a given temperature range inside the tank.
• the auxiliary heating device is defined by an electric resistor inside the tank; a temperature sensor; and a control unit for activating the resistor as a function of the temperature detected.
• the auxiliary heating device comprises an auxiliary heat exchanger inside the tank; a temperature sensor; and a control unit for selectively diverting hot water to the auxiliary heat exchanger, which is defined by a coil fed by the heating circuit.
• a combination gas boiler for producing heating water and domestic water
• the boiler comprising a heating circuit and a domestic circuit, a gas burner, a heat exchanger located along the domestic circuit, and at least one domestic water storage tank located downstream from said heat exchanger; the boiler being characterized by comprising a pump incorporated in said tank, and a domestic recirculating branch for selectively conducting domestic water from the tank to said heat exchanger.
• auxiliary heating devices are provided, those already forming part of the boiler being used.
• integrating the pump in the tank greatly simplifies the recirculating branch, and minimizes the number of component parts and assembly work required to implement recirculation.
• the present invention also relates to a method of operating a gas boiler.
• Figure 1 shows a schematic view, with parts removed for clarity, of a gas boiler in accordance with the present invention and connected to external circuits;
• Figure 2 shows a larger-scale view in perspective of a storage tank of the Figure 1 boiler
• Figure 3 shows a larger-scale section, with parts removed for clarity, of a detail of the Figure 2 tank;
• Figures 4 and 5 show larger-scale exploded views in perspective of a detail of the Figure 2 tank;
• Figure 6 shows a schematic view, with parts removed for clarity, of a variation of the Figure 1 boiler.
• Number 1 in Figure 1 indicates as a whole a wall- mounted combination gas boiler for supplying hot heating water and hot domestic water.
• Boiler 1 comprises a casing indicated by a dot-and-dash line in Figure 1, and is connected to an external heating circuit 2 equipped with radiators indicated schematically by 3, to the water mains 4, to a domestic water user device 5, and to the gas mains 6.
• boiler 1 comprises a heating circuit 7, a domestic circuit 8, a burner 9, and a bithermal exchanger 10 for exchanging combustion- generated heat with both the heating water circulating in circuit 7, and the domestic water circulating in domestic circuit 8.
• Heating circuit 7 comprises a delivery branch 11, a return branch 12, and a bypass branch 13 connecting 5 branches 11 and 12.
• Return branch 12 is fitted with a heating water circulating pump 14, and an expansion vessel 15; and branch 13 is fitted with a bypass valve 16.
• Domestic circuit 8 comprises a branch 17 for feeding
• circuit 8 also comprises a temperature probe 23 located along branch 18, between heat exchanger 10 and tank 20; and boiler 1 comprises an
• tank 20 extends along an axis A, and comprises a cup-shaped body 25 open at one end; and a pump 26 fitted to, so as to form the cap of, cup-shaped body 25.
• Cup-shaped body 25 is made of plastic
• fitting 25 material extends along axis A, and comprises an end wall 27, a truncated-cone-shaped lateral wall 28 (tapering at an angle of close to zero) , longitudinal stiffening ribs 29, and transverse stiffening ribs 30.
• Three fittings 31, 32, 33 are located along cup-shaped body 25 to connect tank 20 to branches 18 and 21. More specifically, fitting
• fitting 31 is located along wall 28, close to wall 27, to connect tank 20 to branch 18 from exchanger 10, and therefore defines a domestic water inlet of tank 20;
• fitting 32 is located at pump 26 to connect branch 18 supplying user device 5, and defines a domestic water outlet of tank 20; and fitting 33 is located on the opposite side to fitting
• body 25 comprises, at the open end, a flange 34 having, inside, a shoulder 35 perpendicular to axis A, a cylindrical wall 36, and a groove 36A ( Figure 4) extending along wall 36 and parallel to axis A, so as to form a seat 37 for pump 26.
• pump 26 comprises a motor assembly 38 and a diffuser 39, which are fitted to cup-shaped body 25 to form tank 20.
• Motor assembly 38 comprises a synchronous electric motor 40; a shaft 41 ( Figure 3); a radial-blade impeller 42; and a one-piece support 43 incorporating motor 40, and from which shaft 41 projects partly, and impeller 42 projects completely.
• Motor assembly 38 comprises a rotor 44 incorporated in support 43.
• support 43 comprises a shell 43A enclosing rotor 44; and a flange 45, from which impeller 42 projects, and along which is located a cylindrical projection 46 extending about axis A. That is, shell 43A and flange 45 are formed in one piece with no openings, and are made of plastic material permeable to electromagnetic waves, so that, in addition to supporting the component parts of motor assembly 38,
• support 43 also acts as a cap for cup-shaped body 25.
• Diffuser 39 is formed in one piece of plastic material, is cup-shaped, and comprises a flat wall 47 perpendicular to axis A, and from which projects a cylindrical outer wall 48 having a rib 49 parallel to
• Diffuser 39 also comprises a volute 50 projecting on the opposite side to wall 48, and comprising a central suction hole 51 coaxial with axis A, and a lateral delivery hole 52 for connecting volute 50 to fitting 33.
• Diffuser 39 is housed inside seat 37 with wall 47 resting
• boiler 1 also comprises a control unit 54, which receives signals from flowmeter 19 and probe 23, provides for on-off control of burner 9 and motor 40 of pump 26, and provides for setting external data, such as the desired domestic hot water temperature.
• boiler 1 operates as follows.
• tank 20 contains a mass of relatively hot domestic water heated in the course of the previous draw.
• the temperature of the domestic water in tank 20 gradually falls.
• pump 26 is activated, and the domestic water is recirculated through exchanger 10 and tank 20, while probe 23 detects a temperature T R related to the domestic water temperature.
• the temperature values T R are compared with a set value T SF . ⁇ ; and, when the detected temperature T R is below the set temperature T SET? burner 9 is lit, and pump 26 is kept running until temperature T R reaches the set temperature T SF .
• number 55 indicates a boiler mostly comprising component parts similar to those of boiler 1, and which are indicated in Figure 6 using the same reference numbers as in Figure 1.
• Boiler 55 substantially differs from boiler 1 by bithermal exchanger 10 being replaced by a primary exchanger 56, which provides solely for heating heating water, and by a secondary exchanger 57 for transferring heat from heating circuit 7 to domestic circuit 8.
• tank 20 and probe 23 are located along branch 18 of domestic circuit 8, downstream from secondary exchanger 57.
• Heating circuit 7 comprises a recirculating branch 58 connecting branch 11 to exchanger 57; a branch 59 connecting exchanger 57 to branch 12; and an electrically controlled three-way valve 60 at the junction of branches 59 and 12.
• control unit 54 is connected to three-way valve 60 and to pump 14 to regulate recirculation and heating of the heating water through exchangers 56 and 57.
• exchanger 57 the heating water yields heat to the domestic water. Operation differs from that described above by the temperature in tank 20 being maintained by recirculating the heating water and the domestic water. In all other respects, the temperature of the water in tank 20 is maintained as described with reference to the previous embodiment .
• tank 20 of preferably 2 to 5 litre capacity, a pump 26 of 2 to 6 litre/minute capacity, and a synchronous electric motor 40 of about 20 W, which provide for extremely short temperature-restoring cycles with very little electricity consumption.
• tank 20, by incorporating pump 26, also has the advantage that hydraulic testing of tank 20 actually also comprises hydraulic testing of pump 26.
• tank 20 is compact and made of plastic material .

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• Engineering & Computer Science (AREA)
• General Engineering & Computer Science (AREA)
• Chemical & Material Sciences (AREA)
• Thermal Sciences (AREA)
• Combustion & Propulsion (AREA)
• Mechanical Engineering (AREA)
• Physics & Mathematics (AREA)
• Steam Or Hot-Water Central Heating Systems (AREA)
• Heat-Pump Type And Storage Water Heaters (AREA)
• Gas Separation By Absorption (AREA)
• Treating Waste Gases (AREA)
• Glass Compositions (AREA)
• Percussion Or Vibration Massage (AREA)
• Adjustment Of The Magnetic Head Position Track Following On Tapes (AREA)
• Instantaneous Water Boilers, Portable Hot-Water Supply Apparatuses, And Control Of Portable Hot-Water Supply Apparatuses (AREA)

Priority Applications (2)

Applications Claiming Priority (2)

Publications (1)

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Family Applications (1)

Country Status (8)

Cited By (3)

Families Citing this family (2)

Citations (3)

• 2003
  • 2003-02-21 IT IT000319A patent/ITMI20030319A1/it unknown
• 2004
  • 2004-02-20 DE DE602004005671T patent/DE602004005671T2/de not_active Expired - Lifetime
  • 2004-02-20 ES ES04713083T patent/ES2283987T3/es not_active Expired - Lifetime
  • 2004-02-20 WO PCT/EP2004/050182 patent/WO2004074744A1/en active IP Right Grant
  • 2004-02-20 CN CNB2004800048630A patent/CN100516704C/zh not_active Expired - Fee Related
  • 2004-02-20 EP EP04713083A patent/EP1595097B1/en not_active Expired - Lifetime
  • 2004-02-20 PL PL376936A patent/PL211041B1/pl unknown
  • 2004-02-20 AT AT04713083T patent/ATE358801T1/de not_active IP Right Cessation

Patent Citations (3)

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