Viair 85-105 Weatherproof Pressure Switch with 40A Relay


  • One of the best pressure switches on the market. Turns your compressors on when pressure goes below 85 PSI, and automatically turns off once pressure reaches 105 PSI.

    You cannot make a warranty claim on your Viair Compressor without using this device.

    Tested to last over 10,000 cycles. This heavy duty, moisture resistant pressure switches come with built-in relays for longevity.

    Leads are pre-fitted with insulated 14in male push-to-connect terminals. Each lead wire is clearly labeled for easy electrical hook up.

  • Use With The Following To Run At 105 PSI:

    • Viair 275C (Partnumber: AC-275)
    • Viair 280C (Partnumber: AC-280)
    • Viair 325C (Partnumber: AC-325, AC-325C)
    • Viair 330C (Partnumber: AC-330, AC-330IG)
    • Viair 350C (Partnumber: AC-350, AC-350C)
    • Viair 400C (Partnumber: AC-400, AC-400C)
    • Viair 450C (Partnumber: AC-450, AC-450C, AC-350IG)

    May Be Used As A Replacement With:

    • 150 PSI Shocker Train Horn Kits (Partnumbers: HK-S4-240, HK-S4-328, HK-S4-340, HK-S4-540)
    • 150 PSI AirChime Train Horn Kits (Partnumbers: HK-P3-528, HK-K3-540, HK-K5-540)
    • 150 PSI Outlaw Train Horn Kits (Partnumbers: HK-230-328, HK-231-328
    • HornAir 150 PSI Onboard Air Systems (Partnumbers: HA-232, HA-240, HA-540, HA-840)
    • Viair 150 PSI Onboard Air Systems (Partnumbers: AS-232, AS-240, AS-245, AS-232D, AS-235D)
    1. Moisture Resistant
    2. Built-In Relay
    1. One Viair 85/105 PSI Pressure Switch with Built-In Relay
    1. Part Number: PS-105R
    2. Ports: 1x ⅛″ NPT male
    3. Turn-Off Pressure: 105 PSI
    4. Restart Pressure: 85 PSI
    5. Voltage: 12 Volts DC
    6. Max Amps: 40 Amps
    7. Length: 4.25″ (107.95 mm)
    8. Width: 2.25″ (57.15 mm)
    9. Weight: 1 lb (0.45 Kg)


This product contains chemicals known to the state of California to cause cancer.