Air from vents always warm

2000 FORD F-250
425,000 MILES • 7.6L • V10 • 4WD • AUTOMATIC
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BARBARA HARRIS
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  • 2 POSTS
In the past with the temperature adjustment set to cool and outside air it has been comfortable.
Now it blows out warm air at the cool setting and hot when turned up. I have replaced the blend door actuator and the temperature potentiometer. The blend door appears to be working when I had everything apart. Is there a possible vacuum that diverts from the heater core when set for cool? Sure do not need warm air blowing out in the summer.
Jun 28, 2017 at 9:10 AM
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HMAC300
  • CERTIFIED EXPERT
  • 48,601 POSTS
check for a vacuum leak first and check to see if motor is working where arrow is that is an air inlet and probably not working or stuck.
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Jun 28, 2017 at 9:51 AM
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BARBARA HARRIS
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Thanks HMAC300. I will check that out on my days off. I only remember seeing a vacuum valve on the shifter for the vent control, but will get the glove box out again and a brighter light to see if it is tucked back under further.
Jun 28, 2017 at 10:01 AM
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HMAC300
  • CERTIFIED EXPERT
  • 48,601 POSTS
all the doors except for temperature are operated by vacuum. you might also check if you have a water valve for heat as that should have vacuum all the time except when on heat. it may be a bad valve as well although it does not show one that will be on heater line or engine.
Jun 28, 2017 at 11:52 AM