FORD E 150 HEAT AND COOLING
MY FORD VAN E 150 HEATER CORE HAS TO HOSES , SOME ONE PUT OPEN & SHUT VALVE ON THEM BOTH IF I WANT AC I TURN THEM BOTH OFF IF WANT HEAT I TURN THEM ON , CAN I TURN THEM ON ,THE WAY THEY SHOULD BE , AND BE ABLE TO SWITCH THEM FROM THE AC CONTROL SWITCH. MAYBE THE BLEND DOOR IS NOT WORKING NOT SURE