Faulty thermostat. Plugged heater core. Temp blend door malfunction.
The blower on the back heater may need to be replaced on the 2000 Ford Winstar.
you may not have the heater water hoses plugged in
probably the heater core is clogged
Leak in heater core. Replace core.
One of the reasons a 2000 Jeep Cherokee heater would randomly blow cold air and then hot air and then cold might be that there is a problem with the hot/cold duct. The air or a vent might be inadvertently blowing periodically.
heater core possibly plugged and leaking
The front expansion valve is clogged.
heater will not blow on a 1996 ford contour
if the heater does not blow out warm air change the setting.
It doesn't really blow it out it just warms the cold air.
Could be a bad thermostat.
Poor coolant circulation from a plugged up heater core. Try flushing the heater core and replacing the thermostat.
Probably your thermostat
Low coolant in the system. Defective heater control valve. Clogged heater core.
it has a partially clogged heater core.replace the heater core
The heater does not blow air because it emits infrared rays that have heat molecules within them, thus releasing heat, not blowing it. A heater does not blow air becasue there is no moving air source within the heater. The heater emits infrered rays that cause heat to slowly flow out of the heater.
either need a blend door accuator or a heater box
The heater blend doors have failed. It is likely that the drivers side has failed shut whilst the other side is stuck partly open.
Your heater will blow cold air only.
The temperature blend door may be at fault.
The heater might blow cold air in a 2000 Silverado because the thermostat is sticking and not changing from cold to heat. The thermostat is usually located in a hose that leads from the radiator to the motor.
You need to replace the heater coil !
It is either your water pump or your thermostat