Combination heating system for recreational vehicles and boats

A combination heating system that combines forced air heating, domestic water heating, and hydronic heating in one self-contained system, the combination heating system comprising:

• a combustion chamber;
• a combustion heat exchanger receiving heat from the combustion chamber, wherein the combustion heat exchanger includes first fins extending outward from the combustion heat exchanger, wherein at least some of the first fins have a profile that is at least partially curved;
• a glycol tank having:
• an outer wall,
• an inner wall, wherein glycol is contained between the outer wall and the inner wall, wherein the inner wall forms a hollow passageway through which the combustion heat exchanger extends, and
• second fins extending inward from the inner wall toward the combustion heat exchanger, wherein the first fins interdigitate with the second fins in a spaced-apart manner such that airgaps exist between adjacent interdigitated ones of the first fins and the second fins;
• and
• a blower that moves heated air across or through the combustion heat exchanger.

A method of combustion heating a recreational vehicle with a self-contained heating system that combines forced air heating, domestic water heating, and hydronic heating in one unit, wherein the method includes:

• activating heating of glycol in a glycol tank via a combustion chamber heating a combustion heat exchanger extending in a hollow passageway formed through the glycol tank, wherein the combustion heat exchanger includes first fins extending outward from the combustion heat exchanger toward inner walls of the hollow passageway, wherein at least some of the first fins have a profile that is S-shaped or forms at least one sinusoidal wave form;
• actuating a blower to move heated air across or through the combustion heat exchanger;
• sensing periods of low heat demand via one or more sensors or settings;
• and
• shutting off the combustion chamber during the periods of low heat demand, while energy stored in the glycol tank continues to provide heat to be used by the self-contained heating system.