Q: Heater is blowing cold air 1999 Hyundai Elantra

asked by on December 14, 2016

I have replaced the thermostat, flushed the system and felt all the hoses and they are hot. I am told that it may be a blend door actuator. I took out the glovebox to get to the blower and what I think is the actuator (vacuum switch). I am not sure the switch I am looking at is the blend door actuator. It works to switch to defrost and internal ventilation.

Where is the blend door actuator and how do I replace it. Is it vacuum or electronic?

My car has 119000 miles.
My car has an automatic transmission.

Heater is not working Inspection $94.99 - $114.99 Get a Quote

Hi there - yes, it could be the air blend door stuck in the outside air (cold) position). The lack of heat could also be the heater control valve or it’s controlling switch or control which is not allowing hot water into the heater core. I would recommend having a heater inspection by a mobile, professional mechanic, such as one from YourMechanic, who will come to your location, diagnose this problem, give you an accurate assessment of damage and cost estimate for repairs.

Hi there. The blend door actuator is located toward the bottom of the HVAC box. It may be difficult to access, let alone replace. It looks like it may be located on the driver side of the box. One way to check for sure is to operate the controls while watching each actuator; the one that does not move with any controls is the target. I suggest having a qualified technician perform an inspection to avoid replacing unnecessary parts or causing undue damage. Your Mechanic has several technicians available that can assist you with a car has no heat inspection.

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