燃やす
alternative
appliance
background
boiler
briquette
central
chamber
closeup
component
condenser
condensing
consume
consumption
dark
device
domestic
door
economical
energy
environmentally friendly
fire
fireplace
fuel
glove
hand
heat
hold
home
hot
human
hydraulic
indoors
industrial
industry
interior
man
metal
opening
pellet
pipe
power
red
solid
solid fuel boiler
solidfuel
system
technology
warmth
wood