Ac running, blower running, no air flow. replaced filter. is there a control unit to open or close in the duct?

The blower must be operating during the test procedure
for the blower pressure switch. Start by checking the
voltage between test point 1 and the common and
normally open contacts of the air flow switch.
Leaving the black lead of the meter on test point 1, check
the voltage at test point 11. If there is not 20-28 Volts
AC at this point, the eight-pin wire harness is faulty and
must be replaced. If 20-28 Volts AC is detected at this
point, then move the red lead of the meter to the Air Flow
Switch NO contact.
If 20-28 Volts AC is detected at this point, the device in
this circuit is closed and the circuit is working properly.
If there is not 20-28 Volts AC at the Air Flow Switch
NO contact, the pressure switch contacts are open. This
is usually due to a blower speed problem or a problem
with the air pressure tube connection between the blower
housing and the switch.
Be sure that the blower is on and that it is working
properly. Check that the gray flexible tube between
the blower pressure switch and the blower housing
is connected at both ends and has no holes or splits.
Replace the tube if necessary. If there is no problem with
the blower or the tube, check for blockages in the vent,
flue or heat exchanger that would prevent air flow. If no
blockages are found, replace the pressure switch.
If the Air Flow Switch NO contact shows 20-28 Volts AC
and the ignition control shows an air flow fault, then there
is a bad connection between the blower pressure switch
and the ignition control, or the ignition control is faulty.

This almost always lack of air flow. Pull out the lint filter and vacuum inside, if you don't have a narrow enough attachment, try to blow it out with a shop vac or even one of those compressed air cannisters for computers.

Remove the aluminum duct from the back of the dryer and make sure it is debris free and unkinked. Check the duct connector in the back and make sure there is no obstructions or lint build up there. Lastly check the vent leaving your house, make sure it is not clogged and that it opens and closes freely and easily.

Turn the dryer on without reattaching the duct, and check that air is flowing out of the back of the dryer, if not, your blower is faulty and will have to be replaced.

If you have hard ducts, you can use some flex duct between the supply plenum and the hard ducts as a way to quiet the noise down.

Sounds like the flap door is not closing. Does the air come out of the defrost ducts and heat ducts?

Crushed duct, restricted air flow in the return air duct. Failing blower motor dirt build up on scroll cage for blower motor. Could also have an open duct in your supply trunk line.

Without more info I am guessing you have an air flow problem.ckeck filter and return air duct

i had a similar problem, and a six inch duct and inline booster fan didnt help, the room was just to far away from the furnace and ac. to save energy, i use an oil rad in the winter, and a portable ac in the summer, it works great.my house is a back split, so its a common problem. in the summer, all downstairs dampers should be closed to push the cold air upstairs ,as it will come back down anyway and the basement is cooler as it is. so if you have 4 flores, you close the bottom 2. bungalow you close the basement

Dusty;
Look in the 14x14 hole the ac sets on. See the openings, those are where the air flows through the ceiling. If you block those off you will not get air. The air box kit is for ducted air. If you notice it will direct air to the ceiling ducts.
Thanks for using Fixya
Jerry

The filter is located before the blower if your Coleman is in a mobile home it will be in the door facing. If it is a standard ac/heat application and a regular residential furnace the blower in the cabinet on down flow (ducts in floor) will be above it and possible in the duct connecting in the top. If its the other way (ducts in ceiling) it could be right under the blower. Either of these could have a filter cabinet on the furnace or could have a filter grille at the end of the return air duct (where the air is sucked in).

Please check for any blockage and in the ac duct, IF the duct is clean you need to refill the AC gas and get it serviced as the AC thens to weak over the years ........................







good luck................