Heat pumps below freezing
Central Kentucky is heat pump country: winters real enough to need heating, mild enough that moving heat beats making it. But a heat pump in the cold behaves in ways its owners were never briefed on — and every January the trade fields calls where the machine is fine and the surprise is the problem.
Normal, and only looks broken
Long run times below freezing are design, not failure — a heat pump delivers gentler, steadier heat than a gas flame, and cold mornings mean near-continuous running. Steam rising off the outdoor unit a few times a day is defrost: the machine briefly runs backwards to melt frost off its coil, sometimes with a whoosh and a puddle. Air from the vents that feels merely warm rather than hot is also normal — it is still well above room temperature, just below the temperature of your hand.
What deserves attention is the pattern that never resolves: ice that ARMOURS the outdoor coil and stays there through the day (a defrost failure), a unit that runs nonstop while the house loses ground, or the electric meter suddenly running wild — which usually means the auxiliary resistance heat has quietly taken over for a heat pump that is no longer pulling its weight. The house stays warm; only the bill tells the truth.
The auxiliary heat trap
Backup electric heat exists for the coldest snaps and for defrost — and it costs several times what the heat pump costs per unit of warmth. Two habits hand it the house all winter: setting the thermostat back deep at night and cranking it in the morning (the jump summons auxiliary heat every day), and ignoring a failing heat pump because the house is still warm. Gentle setbacks, or none, suit this equipment; and a January bill far above the neighbours’ is a service call wearing a disguise.
The freezing rain this region gets adds a note: a unit sheathed in glaze ice cannot breathe and will lean on backup until it clears. Keeping the unit’s sides clear of drifted leaves, snow and ice — gently, never chipping — is the one piece of owner maintenance that matters in winter.