AC blows hot

Tiny
KRISTISWOPE
  • MEMBER
  • 2004 MERCURY MARQUIS
Air Conditioning problem Two Wheel Drive Automatic

my ac started blowing hot all of a sudden. We tried to put freon but it did nothing. It doesn't blow warm. It blows hot like the heater is on. The blower works on all settings. Please help
Saturday, May 15th, 2010 AT 4:03 PM

11 Replies

Tiny
KEN L
  • MASTER CERTIFIED MECHANIC
  • 48,363 POSTS
Hello,

It sounds like you have a temperature blend door actuator that needs to be replaced. When these go out it causes the heater to come on. Here isa guide to help you see what you are in for when doing the job.

https://www.2carpros.com/articles/replace-blend-door-motor

Here is what it will be like for your car (below)

Please let us know if you need anything else to get the problem fixed.

Cheers, Ken
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Monday, November 20th, 2017 AT 2:54 PM
Tiny
VEGASCHUCK
  • MEMBER
  • 7 POSTS
  • 2001 MERCURY MARQUIS
  • V8
  • 2WD
  • AUTOMATIC
  • 100,000 MILES
Air Conditioning problem
2001 Mercury Marquis V8 Two Wheel Drive Automatic 100000 miles

Replaced Control Panel and Control module

When A/C is first turned on it has a knocking noise and hot air starts blowing.

Any ideas on what is causing this?
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Monday, November 20th, 2017 AT 2:55 PM (Merged)
Tiny
RASMATAZ
  • MECHANIC
  • 75,992 POSTS
Hi vegaschuck, Welcome to 2carpros and TY for the donation

Could be the compressor is on its way out, air in the system, pressure too high, and loose support mount
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Monday, November 20th, 2017 AT 2:55 PM (Merged)
Tiny
VEGASCHUCK
  • MEMBER
  • 7 POSTS
All of that has been checked. Are there sensors that operate the vent doors between hot and cold?
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Monday, November 20th, 2017 AT 2:55 PM (Merged)
Tiny
RASMATAZ
  • MECHANIC
  • 75,992 POSTS
Could be a door problem with the air mix/blend/mode, also a vacuum and actuator or the HVAC control module itself-it needs to be open up and investigated.
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Monday, November 20th, 2017 AT 2:55 PM (Merged)
Tiny
VEGASCHUCK
  • MEMBER
  • 7 POSTS
Does that consist on taking the dashboard apart to get to those panels?
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Monday, November 20th, 2017 AT 2:55 PM (Merged)
Tiny
RASMATAZ
  • MECHANIC
  • 75,992 POSTS
Yes sir-plus it can get complicated its not an easy job to do, been there don't like it-
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Monday, November 20th, 2017 AT 2:55 PM (Merged)
Tiny
VEGASCHUCK
  • MEMBER
  • 7 POSTS
Is removing the dashboard like on a Thunderbird or is it in pieces?
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Monday, November 20th, 2017 AT 2:55 PM (Merged)
Tiny
RASMATAZ
  • MECHANIC
  • 75,992 POSTS
No its not the same
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Monday, November 20th, 2017 AT 2:55 PM (Merged)
Tiny
TYRA
  • MEMBER
  • 1 POST
  • 2000 MERCURY MARQUIS


https://www.2carpros.com/forum/automotive_pictures/92044_l_48ee2ef9b14b1fa8c06124bb85cbc575_2.jpg



My air conditioner just started blowing hot air a few days ago. When I went to get my oil changed the guy told me i either needed to change my air filter or he saw some cracks in my belt said i might need that replaced. I just bought a brand new cooling fan system July of 05, and I changed the filter that day. Still hot air. I was told to buy Freon...but Im a female I dont know about any of these things......PLEASE HELP ME!!
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Monday, November 20th, 2017 AT 2:55 PM (Merged)
Tiny
JEFFROHOTROD
  • MEMBER
  • 31 POSTS
Get a a/c recharge hose with a gauge. You can check the freon level and fill it with that.
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Monday, November 20th, 2017 AT 2:55 PM (Merged)

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