Q: Why Does It Take a Long Time for a Heater to Warm Up in Winter?

The heater in a vehicle gets its warmth from the engine. The engine has to warm up, and heat up the liquid coolant circulating throughout the engine, before any heat is available for people comfort. During winter, when outside temperatures are lower, that process takes longer. An efficient heater relies on the engine’s cooling system components to all be functioning well.

A few things that cause automotive heaters to work less well are low coolant levels in the radiator, a faulty heater valve, or the thermostat is stuck open. Have a certified mechanic replace your thermostat if necessary or diagnose and repair other cooling system issues, such as leaking coolant.

One more thing to be aware of: it’s possible for a vehicle to be warming up to proper operating temperature, but be unable to provide enough warm air flow from the heater due to a restricted cabin air filter which needs to be replaced.