the side walls such that the top wall 40 is inclined to comprise a cathedral of domed chamber type ceiling for fuel burning chamber 30 the fuel burning chamber top wall 40 preferably comprises four trapezoidally configured sheets a catalyst device 56 is located contiguous to the fuel burning chamber top wall port 42 for catalytic burning of effluent flue gases the catalyst device 56 preferably comprises a honeycomb configuration constructed of platinum coated or palladium coated honeycomb or screen elements suspended just above catalyst 56 is a catalyst cap member 57 this catalyst cap can be a thin stainless steel plate the plate acts to raise the temperature of the top part of the stove i e effluent chamber 44 thus enhancing the combustion efficiency of the catalyst the plate also acts to protect the top of the stove itself from excess heat coming from the catalyst the net effect of the plate acting in concert with the insulation 59 around the catalyst is to create what substantially is a secondary combustion chamber air inlet port 60 to the fuel burning chamber 30 is provided contiguous to the fuel substance air inlet port 60 has a selectively controllable air opening exposed to the environment of stove 10 preferably in the form of the selectively controllable air opening closure device thermostat 61 is coupled to the stove over aperture or port 60 provided in one wall thereof the aperture admits air to the combustion chamber of the stove to oxidize the fuel contained therein a preheating baffle 216 may be secured to the inner surface of the stove wall air admitted through the aperture is preheated by contact.