Device for extracting heat from a fireplace

Device for keeping warm or cooling foods or beverages

Device for minimizing hot water heat loss in a water heater

Device for reopening an ice-bound water source

Device for steam cooking food

Device for supplying outside combustion air to a fireplace

Direct contact water heater

Direct contact water heater

Direct contact water heater

Direct contact water heater

Direct contact water heater with dual water heating chambers

Direct contact water heater with hybrid heat source

Direct contact water heating system

Direct fired hot water generator with more than one heat exchang

Dish for holding food to be heated in a microwave cooking chambe

Dish for holding food to be heated in a microwave cooking chambe

Door for brew kettle

Double boiler and steam cooker

Down-fired U-tube water heater

Draft air control system