the heat blows out the defrost when it should blow out floor vents only
Fuel level, heat or air conditioning up, both high and low, high only, floor only. Center vents are for air conditioning output only, no heat. Heat is designed to blow out side and floor vents only. NOT center. Center is only for air conditioning or summer vents.
If you have the control panel set to the heat setting, it is only designed to blow out on the floor. If you desire hot air out of the middle, you must set the control panel to vent.
vacuum leak the vacuum reservoir is below the left head light, check the hoses
blow me
ANSWER:No. Heat lightning only explodes in the clouds. It doesnt reach the ground. So it isn't harmful to people.
Most likely a bad or disconnected vacuum hose to the defrost/floor selector in the heater ducting.
You have lost engine vacuum to the control head. Look under the hood back near the distributor and there should be a vacuum check valve. it is most likely broken or the vacuum line is loose or broken.
some thing is probley cloging the vents take it appart and ckeck.
You may have a faulty switch that controls the speeds on the a/c blower fan.
Your compressor has possibly stopped working. If you are lucky, the serviceman will only have to replace the freon to get it going again.
the blower resistor is bypassed on high. a direct path to ground. if high is the only operational speed the resistor is bad.
Pliers, screwdriver and mechanic