Altitude matters more than most people realize
Littleton sits around 5,350 feet, and thin air changes how an oven bakes and how a gas Miele Range burns. Recipes brown and rise differently, which sometimes gets blamed on a 'broken' oven that is actually calibrated fine.
On gas Miele Range models, altitude affects the air-to-gas mixture and can leave burners running rich, sooting, or lifting off. We check orifice sizing and combustion, and on electric ovens we verify the sensor calibration so the cavity actually holds the temperature you set. Colorado's dry air is also hard on door gaskets, and a hardened seal lets heat escape and skews baking long before the oven itself fails.