Sign up for The Wire Newsletter!

Freightliner m2 A/C problem. Heater core all frozen/ icy

Discussion in 'Truck Talk' started by kamilski, Jun 25, 2013.

  1. kamilski

    kamilski Active Expediter

    Joined:
    Apr 24, 2012
    Messages:
    25
    Trophy Points:
    33
    Ratings:
    +0 / 0 / -0
    Every now and then my ac stops blowing the right way and it happens because the heater core gets all iced up and frozen and doesn't let the air to flow thru. I was wondering if anyone has experienced this and if there's any way to stop this from happening. Thanks
     
  2. davekc
    Cloud_9

    davekc Senior Moderator Staff Member Fleet Owner

    Joined:
    Nov 6, 2001
    Messages:
    14,927
    Trophy Points:
    755
    Ratings:
    +4,977 / 0 / -0
    Carrier:
    Panther & V3
    Vehicle:
    Lazy-Boy
    That is usually from low freon. Second cause would be a bad expansion valve.
     
  3. BobWolf
    Happy

    BobWolf Veteran Expediter

    Joined:
    Jan 2, 2011
    Messages:
    1,571
    Trophy Points:
    140
    Ratings:
    +192 / 0 / -0
    Carrier:
    Wolf Trucking
    You might be low on refridgerant or have a blockage. First thing you need to find out is what the specs for your truck and the ammount of refridgerant, line preasuers. After that you need a guage set to check how much freon is actualy in the system, and preasures on the high and low side both with the compressor idling and engaged. I dont recomend just adding refridgerant too litte as well as too much can destroy your systeme.

    Any aditional reading and or doing is at your own risk
    If your truck has alot of mileson it, and you have owned it for at least a few months, and you know the pressure specs, and you have the guage set, and the tools, and the knowhow you can try adding one can of refridgerant to the low presure side
    and see if this inproves things if you dont get good results take it to an AC shop.
     
  4. hossman2011
    Zorro

    hossman2011 Expert Expediter Owner/Operator

    Joined:
    May 12, 2011
    Messages:
    300
    Trophy Points:
    95
    Ratings:
    +49 / 0 / -0
    I just replaced the compressor, dryer, expansion valve in my M2.. compressor was bad and leaking. Be sure to have them look at your hoses while it is apart..... Great people in the Houston area... Jordy's truck and trailer parts.. fair and fast...know what they are doing
     
  5. spongebox1

    spongebox1 Seasoned Expediter

    Joined:
    Dec 23, 2012
    Messages:
    643
    Trophy Points:
    70
    Ratings:
    +71 / 0 / -0
    My m2 does the same thing, I just replaced the evaporator coil, condensor and it would freeze up from time to time, I took the cab filter door off and found debris blocking the drain hole, cleaned out the drain tube and seems to be working better now

    Sent from my VS910 4G using EO Forums mobile app
     
  6. Dynamite 1
    Fine

    Dynamite 1 Moderator Staff Member Fleet Owner

    Joined:
    Apr 7, 2005
    Messages:
    3,992
    Trophy Points:
    355
    Ratings:
    +1,137 / 1 / -0
    Carrier:
    Load One
    Vehicle:
    Straight Truck
    There is also a resistor that can be bought that plugs inline in the temp probe that is in the front of the cabin filter housing that also helps with the problem. Was common when the M2's first came out. Any dealer that does expedite units should know about and have or be able to get the resistor. You can google the problem and find info on it but by all means check out everything else also.
     
  7. Monty

    Monty Expert Expediter

    Joined:
    Mar 7, 2011
    Messages:
    1,752
    Trophy Points:
    113
    Ratings:
    +2 / 0 / -0
    Carrier:
    Retired from Express America
    Consider what is freezing ..... (that will be the humidity in the air). An occasional "thaw out" of the system by turning the a/c off for a bit can be helpful.
     
  8. BobWolf
    Happy

    BobWolf Veteran Expediter

    Joined:
    Jan 2, 2011
    Messages:
    1,571
    Trophy Points:
    140
    Ratings:
    +192 / 0 / -0
    Carrier:
    Wolf Trucking
    Have you checked BOTH A/C coils Condenser behind the grille and Evap in the heat/airbox and any cabin filters. If theyre crudded up you wont have airflow and you will turn your A/C into an icemaker. Most hardware stores sell a condenser brush th clean the coils use the brush and a shop vac. You will have to disassemble the dash to get to the evap coil.

    Bob Wolf
     
Loading...

Share This Page