A/C not working on Max

Discussion in 'Heavy Duty Diesel Truck Mechanics Forum' started by Razorwyr, May 1, 2020.

  1. Razorwyr

    Razorwyr Road Train Member

    2,284
    2,824
    Jul 27, 2010
    Meridian, Mississippi
    0
    Ok, so I have a 2015 Prostar and my ac quit blowing icy cold a few weeks ago. I just figured I had a leak and/or just time for a recharge so I bought a kit. Temp outside was around 65-70 the day I checked it, low side was at about 60 psi. After doing a better visual inspection, and not seeing anything immediate, I decided to play with the switches. Air blows strong on all settings, but not cold enough. "NORM"al a/c setting feels cool (not cold), but "MAX" blows warm. Defrost and heat work fine. Its mid 70s outside today, so not sure why normal is at least trying to work and MAX has decided to self-quarantine. What are some possible causes?

    Also bunk a/c stopped blowing cold on the same day. And on max it blows fairly hard, but not as hard as it does on normal.
     
    Last edited: May 1, 2020
    Reason for edit: Adding note
  2. Truckers Report Jobs

    Trucking Jobs in 30 seconds

    Every month 400 people find a job with the help of TruckersReport.

  3. Razorwyr

    Razorwyr Road Train Member

    2,284
    2,824
    Jul 27, 2010
    Meridian, Mississippi
    0
    .
     
    Last edited: May 1, 2020
    Reason for edit: Delete
  4. Powder Joints

    Powder Joints Subjective Prognosticator

    7,877
    8,174
    Sep 25, 2007
    Rosamond, SoCal
    0
    Could be a vacuum door is not opening or closing, could be most anything.
     
    Razorwyr Thanks this.
  5. Razorwyr

    Razorwyr Road Train Member

    2,284
    2,824
    Jul 27, 2010
    Meridian, Mississippi
    0
    That's what figured and was afraid of. That there isnt just one or 2 possible causes, but I'm going to spend all weekend chasing a ghost. Well, I havent had the truck very long, but I'm changing the air filters with my oil change this weekend. Maybe it's just that stupid and simple.
     
  6. Powder Joints

    Powder Joints Subjective Prognosticator

    7,877
    8,174
    Sep 25, 2007
    Rosamond, SoCal
    0
    See if the lines from to the cab are freezing up, make be its not circulating properly
     
    Razorwyr Thanks this.
  7. Razorwyr

    Razorwyr Road Train Member

    2,284
    2,824
    Jul 27, 2010
    Meridian, Mississippi
    0
    I was trying all of the fuses and checking to make sure everything was plugged in and noticed the lines were either hot or just roughly ambient temp. I checked the compressor the other day and thought it was spinning, but rechecked it today and it was not, so I'm guessing that's my problem.
     
  8. lights787

    lights787 Light Load Member

    118
    41
    Sep 26, 2019
    0
    Funny, you mention this. I have the same issue with my 2015 ProStart+. My dilemma is that I have already paid the International Dealership Service department $4k to fix the AC. At first, they changed the compressor and everything else. In less than 100 miles it stopped working again so I took it back and was told the Condensor somehow took a rock and had to be replaced. So here comes another $1k bill on top of $3k I had paid them. I have not driven the truck even 500 miles and it was blowing arctic cold air then all of sudden it stopped working. Mind you this has taken over 11 days of shop time and I have yet to see what else is wrong with the AC. My issue is I am beginning to believe this dealership is either gouging me or they don't what they are doing. I mean the Truck has only 177k miles on it and everything else works great in it.

    I'll post the update here I'd love to hear your opinion. I am thinking about disputing the whole charge if it breaks again or if they want more money to get this fixed and taking it elsewhere.

    What is a good alternative to an International Dealership to get mechanical work done?
     
    Razorwyr Thanks this.
  9. Powder Joints

    Powder Joints Subjective Prognosticator

    7,877
    8,174
    Sep 25, 2007
    Rosamond, SoCal
    0
    Sometime its confusing as the outside of the pulley on the clutch spining,but the clutch is not engaged, you may just need to have the clutch on the compressor changes since you already mentioned you had pressure on the low side
     
    Razorwyr Thanks this.
  10. Razorwyr

    Razorwyr Road Train Member

    2,284
    2,824
    Jul 27, 2010
    Meridian, Mississippi
    0
    I dropped mine at the dealership about 20 mins ago, we shall see what they say. Which dealer did you go to? Hopefully not the same one I'm at lol
     
  11. x1Heavy

    x1Heavy Road Train Member

    34,017
    42,141
    Mar 5, 2016
    White County, Arkansas
    0
    When my AC went bad I had the TA in Savannah replace the entire system after they checked and said yep its gone.

    The money, yep thats gone too. 1500 dollars.

    Thats when the yelling started. They raged that I could have gone all the way to the midwest throwing away two tanks of fuel for 700 dollars in work.

    So I yelled back, what part of dumb do they not understand money math?

    The yelling started all over again.

    Right. Ice sheets coming off my tractor that summer. THUNK! Sound of comfort.
     
    Razorwyr Thanks this.
  • Truckers Report Jobs

    Trucking Jobs in 30 seconds

    Every month 400 people find a job with the help of TruckersReport.