Home › Forums › Stay Dirty Lounge › Service and Repair Questions Answered Here › 2006 Jeep Commander Heater Core suspected clogg › 2006 Jeep Commander Heater Core suspected clogg January 20, 2020 at 3:23 am #895798 Richard KirshyParticipant Core flow direction isn’t really important considering you should flush the core both directions. If there is a concern about which hose goes where just mark one hose and the port it attaches to.