Patent ID: 7410619

Claim:
A system for keeping a medium in a container warm, comprising; a container having a heatable surface through which heat may be conducted into a medium within a container; a supply of hydrogen; a thermostatic valve having a temperature responsive member disposed in proximity with said container and operable to open in response to said temperature responsive member being below a first temperature and to close in response to said temperature responsive member being above a second temperature, said second temperature being higher than said first temperature, said valve connected to said supply to provide, when said valve is open, a source of hydrogen for combustion to heat said heatable surface; and a hydrogen/oxygen catalytic combustor selected from (a) an ejector combustor comprising— a chamber having a heating surface, through which heat is to be conducted to a heat utilizing apparatus; an ejector having an outlet, a principal inlet in fluid communication with said source of hydrogen, and a secondary inlet in fluid communication with atmospheric air; and a hydrogen/oxygen combustion catalyst disposed between said ejector outlet and said chamber; and (b) a diffusion combustor comprising: a hydrogen/oxygen combustion catalyst having first and second sides; a heating surface, through which heat is to be conducted to a heat utilizing apparatus, separated from said first side of said catalyst by a first space; a hydrogen conduit for conducting hydrogen from said source to said first space; and a diffusion control plate disposed in atmospheric air and separated from said second side of said catalyst by a second space; said heatable surface in contact with one of said heating surfaces, whereby hydrogen passing through said valve is catalytically combusted to heat the medium within said container.