1. FIRE BEHIND FURNACE PANELING 8:30 AM MST I NOTICED SMOKE COMING FROM UNDER THE FURNACE PANEL. I SHUT DOWN THE FURNACE AND OPENED THE FURNACE PANEL. UPON OPENING, I DISCOVERED THE LINOLEUM BURNING IN A SIX INCH DIAMETER OVAL AREA. I EXTINGUISHED THE FIRE. EXAMINATION SHOWED THE FURNACE FEEDS THE DUCT SYSTEM UNDER THE FLOOR BY MEANS OF A HOLE IN THE FLOOR THAT IS SUPPOSED TO ALIGN WITH THE FURNACE CHAMBER HOLE. THE SPACE BETWEEN FURNACE AND FLOOR HAS A FITTED GASKET AND ALUMINUM-LIKE FOIL PROTECTING THE FLOOR FROM THE HEATED AIR. HOWEVER, THE HOLE IN THE FLOOR WAS MISALIGNED BY 3" SUCH THAT THE FURNACE SLOT WAS OVERLAPPING 3" OF ACTUAL LINOLEUM COVERED FLOOR. THIS ALLOWED THE FURNACE HEATED AIR TO BLOW DIRECTLY ON THE LINOLEUM AND SET IT ON FIRE. THIS VEHICLE IS LOCATED ON-SITE OF OUR HOUSE BUILDING, SO I ENLISTED HELP FROM THE HVAC CONTRACTOR WORKING ON THE HOUSE; AND WE CORRECTED THE HOLE ALIGNMENT AND PUT IN SHEET METAL, INSULATION, GASKETS, AND HEAT BARRIERS TO CORRECT THE SITUATION. 2. EARLIER HAZARD PROBLEM. SEVERAL MONTHS EARLIER, WHEN ATTEMPTING ACCESS TO BLACK AND GRAY WATER VALVES, IT WAS VERY EASY TO CUT YOUR HAND ON SHARP EDGED SHEET METAL PANELS ABOVE THE VALVES. I CORRECTED THIS PROBLEM BY PUTTING TUBING OVER THE SHARP EDGES. HOWEVER, WHEN I CALLED THE COMPANY ABOUT THIS HAZARD, I WAS TOLD BY A CUSTOMER SERVICE PERSON THAT IT "WASN'T WARRANTY". I EXPLAINED I WAS ALERTING THEM TO HAZARD, DESIGN AND QUALITY CONTROL PROBLEMS. 3. MISALIGNED BATH ROOM DOOR, UNL