99 Expo heat problem

[Kn1cks20]

my heat dose not work, it is blowing out cold air, i have added anti-freeze but that did not help.

[grogden]

check that the temp control knob is actualy working, mine did the same thing i pullled the knob off and moved the control manualy and had heat.a new knob is like $5 and wiil fix the problem(assuming that was the problem)

[mnehky]

If it's the fan. or lack thereof there is a very inexpensive resistor that goes in the fan dial.

If it is warm to hot when accelerating, then cold when not accelerating, let me know what it was, 'cause thats what mine does.

If it's constant cold and the dial is working properly, the coolant to water ratio could be too much water, or a clogged or bad heater core. Does it have multi zone heat (front and rear controls)? If so, do they both blow cold or does only one?