Possible causes

  • Power supply AC input voltage is not within normal range (140v - 280v)
  • Module drive board bus voltage not within normal range (290v - 410v)


  • Test the input voltage between L1 & L2 on the primary input.
    • If this is not stable and within spec, please call an electrician to correct the problem
  • Measure the bus voltage as shown below.
    • If the main power is stable and this measurement is incorrect... please contact Arctic Heat Pumps as the drive board may require replacement.