Volvo vnl 670 2011, Fan short cycling when ac on

Discussion in 'Volvo Forum' started by RoadRanger^^, Jun 25, 2025 at 3:40 PM.

  1. RoadRanger^^

    RoadRanger^^ Light Load Member

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    Back again fellas,

    I have issues with my ac not cooling off enough. Here is the story. When i turn on the ac compressor runs for 30 seconds then shuts off and fan runs for 3-4 seconds and repeats and I’m thinking fan running that short is not enough to cool of the compressor. My friends truck when the fan kicks on runs around 50-60 seconds. Yesterday one of the airline broke and the fan was constantly on and the AC was blowing ice cold so i know the truck is not low on freon there is no leak in the system. What could be the issue ? Possible faulty high pressure switch ? No codes so far on the dash

    thank you
     
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  3. Big Road Skateboard

    Big Road Skateboard Road Train Member

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    You need to put some gauges on it. Sounds like it could be overfull, but gauges will verify what pressures are doing.

    Sounds like high pressure is spiking causing fan to engage and kicking out the clutch
     
    RoadRanger^^ Thanks this.
  4. RoadRanger^^

    RoadRanger^^ Light Load Member

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    Do you know by any chance what should be the numbers ? Or it depends of the outside temperatures ?
     
  5. Big Road Skateboard

    Big Road Skateboard Road Train Member

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    Yeah I do, but it won't do you any good. Just hook em up and let us know what thet do. Even better, uplosd a video
     
  6. RoadRanger^^

    RoadRanger^^ Light Load Member

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  7. Big Road Skateboard

    Big Road Skateboard Road Train Member

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    Most put ir on YouTube then link it
     
  8. Big Road Skateboard

    Big Road Skateboard Road Train Member

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    Looks overcharged. Have you worked on it? I'd be getting some freon out of the system and see how it reacts.

    With the fan on, high side should be 170-200ish
    Low side 30-45ish

    Those are rough #'s, several factors in play there
     
    Last edited: Jun 25, 2025 at 7:19 PM
    RoadRanger^^ Thanks this.
  9. RoadRanger^^

    RoadRanger^^ Light Load Member

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    Yes i worked on it maybe couple months and recharged it myself with cans.
     
  10. Big Road Skateboard

    Big Road Skateboard Road Train Member

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    See my edited post above. I'm surprised you haven't burnt up the clutch already
     
    RoadRanger^^ Thanks this.
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