From the shop
Denver HVAC written plainly
No heat, a furnace at a mile high, cooling that falls behind, and whether the furnace stays. Within 40 miles of Denver.

Latest
The furnace quits on the first cold night
Denver heating calls pile up when the first real cold hits. Most of them are a furnace that sat all summer, not a dead house.
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A Denver furnace is not a sea-level furnace
At 5,280 feet the air holds less oxygen. A gas furnace left on factory settings burns wrong.
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The AC runs all day and the house stays warm
Denver summers are shorter than a hot-climate city, and the cooling still falls behind. Thin air and a blocked coil are the usual reasons.
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Heat pump, furnace, or both
A lot of Denver houses do not need the furnace pulled. A heat pump can carry the mild hours. The furnace stays for the cold ones.
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