2005 ford 450 hvac vaccuum leak?
Greetings! I've been to a couple RV and Ford boards and remember someone with a similar problem. He said the vacuum reservoir was replaced to clear his problem. My take is that all cabin air is direc...
Forum Discussion
No the air isn't routed through the heater core before it gets to the different stages (for a better word. There is a blend door before the heater core which directs the air to where ever you set the controls, whether it be heat, vent (outside air) or A/C, adding heat redirects the blend door and heater shut off to start to open so some air goes through the heater core thus warming the air if requested. You'll have to look under the dash and watch which door is moving when you operate the controls. You may not see all the doors/vacuum motors as some may be inside the housing. I'll try and dig up the schematic for you vehicle.
