The front expansion valve is clogged.
Your heater will blow cold air only.
check the antifreeze level in the radiator, when a heater blows cool/cold air there is not enough antifreeze/water in the radiator.
Probably your thermostat
It doesn't really blow it out it just warms the cold air.
There is a divertor controller under the dash that controls between heat and cold. Sometime the wireing harness works loose.
you need to replace your heater core
it wont blow heat itll blow cold air
heat works in back not in front front blows hot for a few mins then cold
heater core possibly plugged and leaking
you are low on coolingliquid !
Probably because coolant level is low
No, not if it's on a heat setting. Most home thermostats have a "Fan" setting that will blow cold air if the attic is cold.
you may not have the heater water hoses plugged in
need Answerdid you fine out why this happens I got the samr problem The rear A/C has a heater blend door actuator that is stuck open to the heater core. I purchased one at Rockauto.com part #1572792.
Get the air out of your heater core.
Your problem sounds like the common blend door problem on the Ford Expeditions, and Ford Explorer. Check related link below
the heater core was stopped up just flushed it out ok now
heater hoses might have been disconected
You have run out of coolant, or the heater matrix is blocked.
Could be a bad thermostat.
Cause its broke!
Low on coolant, stuck open thermostat, plugged heater core, faulty temperature blend door,