Oak Hills sits at 3,600-4,200 ft elevation, which makes furnace repair higher-stakes than in lower-elevation HD cities. Winter overnight lows here hit the high teens regularly, lower than Hesperia or Victorville. When a furnace fails on a 17°F overnight, indoor temps can drop to dangerous levels within hours. Fast dispatch matters more here than in milder climates. Oak Hills is mixed gas service: SoCalGas covers parts of the area, propane covers others. Propane furnaces have different orifice sizing, regulator work, and tank-supply diagnostics. We confirm fuel type at the door and carry both natural gas and propane parts on every Oak Hills dispatch. Larger Oak Hills custom homes (2,500-4,000+ sq ft) typically run 100-120k BTU furnaces vs. the 60-80k systems common in tract homes. Bigger furnaces means bigger components: bigger ignitors, bigger gas valves, bigger blower motors. Parts are slightly more expensive but the diagnostic process is the same.