Air conditioning vents do not blow air?

Answer 1

Question is too vague to provide a proper answer.

Is the air conditioner compressor working? Have you checked the fuse?

First off the question was formed using the word VENTS and an action word (VERB) BLOW

then the word AIR is not a vague question at all. the asking party did not inquire as to why the air is warm, but to why there is none at all.

Bad blower motor, bad capacitor, systems power switches all on, are you positive that tstat is calling.

Upon initial diagnosis I would check DO I HAVE 120 volts @ the primary side of the transformer, IF YES continue with diagnostic, IF NO verify that there is voltage coming from the circuit breaker and all wires are connected, switches are all closed IF YES breaker will need replaced (this is very uncommon as breaker shows in on position but there is no measurable potential between L1-L2 on board ) I continued with diagnostic.

IF 120v is established at transformer and transformer is working correctly you should get between 22-28 volts on secondary side (this is where the power supply for R comes from ultimately off of and into circuit board, should you not get any voltage thru secondary then transformer is bad and needs to be replaced)

THE next step is to make sure all switches are closed and passing continuity, are there any switches or fuze's wired in series that are open, can you actually turn motor by hand is it tight, or does it grind or wobble. Next I would check the Capacitor's Microfarad's as well as see if the motor is pulling hi amperage when comparing to blower rated amp draw door, if motor fails to turn while energized it will still try to consume the energy in the windings of the motor and show a significant amp flow across meter , generally you can hear this type of failure. IE

humming motor or transformer you then un-tapp motor from board and ohm the leads together just as with a compressor the sums of the legs should be equal the greatest or at least close.

One last test before we condim this units blower, try passing continuity thru the Windings to shell of motor, if so then motor needs replaced as it is shorted to ground. If still no blower on, then un-wire tstat at board and jump R-G this should jump fan into running if no action, do not rewire stat to board instead I usually remove door switch circuit and leave the neutral connected to spade at board, remove black wire from fan door switch and place it directly to cool wire to verify motor failure blower with 115v if motor is static need new motor..

NOTE when dealing with ecm motors you use same exact proceedures except you need to check motor module seperatly after assessing 1st inital failure.

NOTE 2 There is also one other reason to have unit calling for cooling but no air is being distributed thru venting, this maybe caused by a dirty indoor coil that was unable to transferring any heat thru frozen block -coil or filter the indoor side this can happen anytime the air flow across coil is signifigantly impinged