Heater

[binx_19]

I was on my way home from work tonight and early in the trip my heat worked. When I arrived at home 15-20 minutes later, cold air was blowing out the vents. Any ideas on what could be going on here? the Temp outside is 38*F

[garbonzo1991gt]

Check the vaccum line next to the evaporator in the engine bay is still hooked up to the heater bypass valve... Looks like a vaccum valve on the heater core hose going back to the firewall. See the gray line in the pic.