Vehicle heater

1. A vehicle heater comprising:

a plurality of heating units, wherein each heating unit comprises a burner unit comprising a combustion chamber for receiving fuel and combustion air and for burning a fuel/combustion air mixture, wherein a separate combustion air delivery device and a separate fuel delivery device are associated with each burner unit, each separate fuel delivery device comprising a separate fuel feed pump for feeding liquid fuel to the combustion chamber of a respective burner unit and each separate combustion air delivery device comprising a separate air blower for delivering combustion air to a respective combustion chamber; and

a heat exchanger device transmitting heat provided in the heating units to a heat carrier medium, wherein the heat exchanger device comprises a heat exchanger zone associated with each heating unit for transmitting heat provided in this heating unit to the heat carrier medium, the heat exchanger device comprising an outer housing unit defining a heat carrier medium flow space relative to an outside, the heat exchanger device further comprising an inner housing unit, which defines the heat carrier medium flow space relative to an inside, towards waste gas flow spaces of the different heat exchanger zones and encloses the heat carrier medium flow space together with the outer housing unit, the outer housing unit comprising an outer housing part defining the heat carrier medium flow space areas of at least two of the heat exchanger zones relative to an outside, the heat carrier medium flow space areas of the at least two heat exchanger zones being separated by a partition of the outer housing part, at least one flow opening being provided in the partition for a flow of heat carrier medium from the heat carrier medium flow space area of one heat exchanger zone to the heat carrier medium flow space area of another heat exchanger zone.

2. A vehicle heater in accordance with claim 1 , wherein the heat exchanger device comprises:

a heat carrier medium inlet; and

a heat carrier medium outlet, wherein the heat carrier medium flow space comprises a heat carrier medium flow space area associated with each heat exchanger zone.

3. A vehicle heater in accordance with claim 2 , wherein at least one of:

the heat carrier medium flow space areas of at least two heat exchanger zones are connected with one another to provide a serial flow of the heat carrier medium; and

the heat carrier medium inlet and the heat carrier medium outlet are provided associated with the heat carrier medium flow space areas of different heat exchanger zones.

4. A vehicle heater in accordance with claim 1 , wherein the inner housing unit comprises an inner housing part defining the heat carrier medium flow space areas of at least two of the heat exchanger zones relative to the inside.

5. A vehicle heater in accordance with claim 1 , wherein the inner housing unit comprises inner housing parts associated with at least two heat exchanger zones, which are formed separately from one another and define the heat carrier medium flow space areas of these heat exchanger zones towards the waste gas flow spaces thereof relative to the inside.

6. A vehicle heater in accordance with claim 1 , wherein one burner unit is arranged next to another burner unit with an essentially parallel waste gas flow direction, the burner unit of one of the heating units receiving a first flow of liquid fuel and a first flow of air, the burner unit of another one of the heating units receiving a second flow of liquid fuel and a second flow of air, the first flow of liquid fuel being located at a spaced location from the second flow of liquid fuel, the first flow of air being located at a spaced location from the second flow of air.

7. A vehicle heater in accordance with claim 1 , further comprising a common waste gas outlet open to waste gas flow spaces of the heat exchanger zones, the common waste gas outlet being associated with at least two of the heat exchanger zones.

8. A vehicle heater in accordance with claim 1 , wherein each burner unit is actuated independent of another burner unit.

9. A vehicle heater in accordance with claim 1 , wherein each combustion air delivery device is operated independent of another combustion air delivery device and each fuel delivery device is operated independently of another fuel delivery device, the burner unit of one of the heating units receiving a first flow of liquid fuel and a first flow of air, the burner unit of another one of the heating units receiving a second flow of liquid fuel and a second flow of air, the first flow of liquid fuel being separate from the second flow of liquid fuel, the first flow of air being separate from the second flow of air.

10. A vehicle heater in accordance with claim 1 , wherein said combustion chamber associated with one burner unit is located adjacent to said combustion chamber associated with another burner unit, said combustion chamber associated with said one burner unit being separated from said combustion chamber associated with said another burner unit via at least a housing of at least one of the one burner unit and the another burner unit.

11. A vehicle heater comprising:

a plurality of heating units, wherein each of the heating units comprising a burner unit to provide a plurality of burner units, each of the burner units comprising a combustion chamber;

a first combustion air delivery device comprising a first air blower;

a first fuel delivery device comprising a first fuel feed pump for feeding liquid fuel, the combustion chamber of one of the plurality of burner units receiving fuel from the first fuel delivery device and air from the first combustion air delivery device;

a second combustion air delivery device comprising a second air blower, the second combustion air delivery device being operated independently of the first combustion air delivery device;

a second fuel delivery device comprising a second fuel pump for feeding liquid fuel, the second fuel delivery device being operated independently of the first fuel delivery device, the combustion chamber of another one of the plurality of burner units receiving fuel from the second fuel delivery device and air from the second combustion air delivery device; and

a heat exchanger device transmitting heat provided in the heating units to a heat carrier medium, wherein the heat exchanger device comprises a heat exchanger zone associated with each heating unit for transmitting heat provided in a respective heating unit to the heat carrier medium, the heat exchanger device comprising an outer housing unit defining the heat carrier medium flow space relative to an outside, the heat exchanger device further comprising an inner housing unit, which defines the heat carrier medium flow space relative to an inside, towards waste gas flow spaces of the different heat exchanger zones and encloses the heat carrier medium flow space together with the outer housing unit, the outer housing unit comprising an outer housing part defining the heat carrier medium flow space areas of at least two of the heat exchanger zones relative to an outside, the heat carrier medium flow space areas of two heat exchanger zones being separated by a partition of the outer housing part, at least one flow opening being provided in the partition for a flow of heat carrier medium from the heat carrier medium flow space area of one heat exchanger zone to the heat carrier medium flow space area of another heat exchanger zone.

12. A vehicle heater in accordance with claim 11 , wherein the first fuel delivery device, the first combustion air delivery device, the second combustion air delivery device and the second fuel delivery device are located at a spaced location from one another.

13. A vehicle heater comprising:

a plurality of heating units, wherein each heating unit comprises a burner unit comprising a combustion chamber for receiving fuel and combustion air and for burning a fuel/combustion air mixture, wherein a separate combustion air delivery device and a separate fuel delivery device are associated with each burner unit; and

a heat exchanger device transmitting heat provided in the heating units to a heat carrier medium, wherein the heat exchanger device comprises a heat exchanger zone associated with each heating unit for transmitting heat provided in this heating unit to the heat carrier medium, wherein the heat exchanger device comprises an outer housing unit and an inner housing unit, the outer housing unit defining the heat carrier medium flow space relative to an outside, the inner housing unit defining the heat carrier medium flow space relative to an inside, towards waste gas flow spaces of the different heat exchanger zones and the inner housing unit enclosing the heat carrier medium flow space together with the outer housing unit, the outer housing unit comprising an outer housing part defining the heat carrier medium flow space areas of at least two of the heat exchanger zones relative to an outside, the heat carrier medium flow space areas of two heat exchanger zones being separated by a partition of the outer housing part, at least one flow opening being provided in the partition for a flow of heat carrier medium from the heat carrier medium flow space area of one heat exchanger zone to the heat carrier medium flow space area of another heat exchanger zone.

14. A vehicle heater comprising:

a plurality of heating units, wherein each of the heating units comprising a burner unit to provide a plurality of burner units, each of the burner units comprising a combustion chamber;

a first combustion air delivery device;

a first fuel delivery device, the combustion chamber of one of the plurality of burner units receiving fuel from the first fuel delivery device and air from the first combustion air delivery device;

a second combustion air delivery device operated independently of the first combustion air delivery device;

a second fuel delivery device operated independently of the first fuel delivery device, the combustion chamber of another one of the plurality of burner units receiving fuel from the second fuel delivery device and air from the second combustion air delivery device; and

a heat exchanger device transmitting heat provided in the heating units to a heat carrier medium, wherein the heat exchanger device comprises a heat exchanger zone associated with each heating unit for transmitting heat provided in a respective heating unit to the heat carrier medium, the heat exchanger device comprising an inner housing unit and an outer housing unit, the outer housing unit defining the heat carrier medium flow space relative to an outside, the inner housing unit defining the heat carrier medium flow space relative to an inside, towards waste gas flow spaces of the different heat exchanger zones and the inner housing unit enclosing the heat carrier medium flow space together with the outer housing unit, the outer housing unit comprising an outer housing part defining the heat carrier medium flow space areas of at least two of the heat exchanger zones relative to an outside, the heat carrier medium flow space areas of two heat exchanger zones being separated by a partition of the outer housing part, at least one flow opening being provided in the partition for a flow of heat carrier medium from the heat carrier medium flow space area of one heat exchanger zone to the heat carrier medium flow space area of another heat exchanger zone.