Where is the check valve located?

Tiny
MBFOR99
  • MEMBER
  • 2000 FORD F-250
  • 5.4L
  • V8
  • 4WD
  • AUTOMATIC
  • 230,000 MILES
Okay, my normally the A/C works great, but when I go into acceleration it goes to default which is defrost then comes back. Now I have that new valve but for the life of me I cannot find the location of that check valve. If you guys know where the valve may be located, please let me know. Thanks, Matt
Saturday, April 2nd, 2022 AT 12:17 PM

1 Reply

Tiny
JACOBANDNICKOLAS
  • MECHANIC
  • 110,144 POSTS
Hi,

As you are aware, the HVAC is vacuum controlled. There could be a leak at any point in the system causing the vacuum to drop and the airflow to change direction.

When you say check valve, I'm not 100% sure what you are referring to. So, I attached a pic below showing the vacuum schematic for the system. Take a look through it and let me know the specific name of the component you are referring to. Once you let me know, I can locate it for you.

Take care,

Joe

See pic below.
Image (Click to make bigger)
Thumb
Was this
answer
helpful?
Yes
No
Saturday, April 2nd, 2022 AT 10:01 PM

Please login or register to post a reply.

Related Defroster Content

Vents Stay in Defrost Mode
GUIDE
Vents Stay in Defrost Mode
Your car's de­froster is de­signed to re­move mois­ture (fog) from the in­side of the wind­shield in cold weather. It can be a safety prob­lem if the de­froster is not work­ing, or...
VIEW MORE