How to tell if the blend door is leaking? | Ford Explorer - Ford Ranger Forums - Serious Explorations

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How to tell if the blend door is leaking?


Well-Known Member
August 18, 2004
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City, State
Year, Model & Trim Level
'93 XLT
I'm a little suspicious my AC is pulling some air in from the heater core, as it dumps more condensation out the bottom than I've ever seen from a car.

This is in MAX mode, when the cabin should dehumidify after a little while.

Is there a way to tell whether my blend door is leaking hot air into the AC stream?

I suspect it because both my heater hoses going to the dash are hot all the time, leaving the barrier between heater core and AC evaporator as the only thing separating hot from cold.