To remove the buildup of creosote tars from the grate and fireplace tools, just take it outside your house and simply hose it down. Then sprinkling an abrasive cleanser on the surface, scrub it with the help of a steel-wool soap pad or a stiff bristle brush. You can also apply some polish on them to make them shine.
Using a wood or coal stove? Put an approved stove board under the unit to shield the floor from the heat and the hot coals, which might fall out. For the maintenance and installation of the unit, follow the manufacturers instructions.