Abstract: A compact hydronic space and water heating apparatus and system is disclosed for use in a recreational vehicle. A liquid heating medium, stored within a low pressure tank, is recirculated through a gas fired heater thereby maintaining a desired set point temperature. The liquid heating medium is further circulated through the vehicles hydronic space heaters to heat the interior of the vehicle. Further fresh domestic water is passed through a heat transfer coil within the tank whereby hot domestic water may be provided. An auxiliary heating device is attached to the tank whereby hot combustion engine coolant may assist in maintaining the temperature of the liquid heating medium within the tank and/or reversed to pre heat the combustion engine if and when needed.

Abstract: A compact hydronic space and water heating apparatus and system is disclosed for use in a recreational vehicle. A liquid heating medium, stored within a low pressure tank, is recirculated through a gas fired heater thereby maintaining a desired set point temperature. The liquid heating medium is further circulated through the vehicles hydronic space heaters to heat the interior of the vehicle. Further fresh domestic water is passed through a heat transfer coil within the tank whereby hot domestic water may be provided. An auxiliary heating device is attached to the tank whereby hot combustion engine coolant may assist in maintaining the temperature of the liquid heating medium within the tank and/or reversed to pre heat the combustion engine if and when needed.

Abstract: A compact hydronic space and water heating apparatus and system is disclosed for use in a recreational vehicle. A liquid heating medium, stored within a low pressure tank, is recirculated through a gas fired heater thereby maintaining a desired set point temperature. The liquid heating medium is further circulated through the vehicles hydronic space heaters to heat the interior of the vehicle. Further fresh domestic water is passed through a heat transfer coil within the tank whereby hot domestic water may be provided. An auxiliary heating device is attached to the tank whereby hot combustion engine coolant may assist in maintaining the temperature of the liquid heating medium within the tank and/or reversed to pre heat the combustion engine if and when needed.

Abstract: Disclosed is a gas instantaneous water heater for use in boats or recreational vehicles comprising a housing divided into a large upper portion and a small lower portion. A gas valve and electric filament lighter are controlled by an electronic module which opens the gas valve and ignites the gas in response to a signal from a sensor capable of sensing water flow or a pressure drop. The heater employs a photoelectric flame sensor and a thermal override switch to shut off the gas in the event the igniter fails to ignite the gas or if the water temperature is excessively high.