Weak A/C after multi freon charging

[Omar_Eltahan]

I have a chery A5 car, its model has only fresh air filter, no filter for circulation a/c. I was running a/c with low and fan speed at 2 or 3 Max. I'm in Egypt so temp. Reaches 40+ easily in summer. A few months ago a/c went weak in air flow not cooling temp. Means that front seats passengers will feel ok with fan on 4+ while back seat passengers feel hot even with the back air vents located in middle console. freon Ratio is fixed and I've changed freon machines many times by changing places, also I've cleaned the evaporator and external fresh air filter, even changing it also I've cleaned the blower, all of that without positive results. Do I have to change the blower or you may recommed another solution?

 

[SHOZ]

Maybe a blend door problem in the duct work?

 

[nthach]

How are the system pressures between the low and high side? Are the blend doors properly switching over between the heater core and evaporator? Did you blindly add refrigerant without checking for leaks and the system high/low side pressures?

 

[Omar_Eltahan]

I've tested pressure and leak on vacuum pressure machine and everything is ok. What're blend doors?

 

[SHOZ]

Blend door is under the dash after the blower and before the evap and heater core. Usually a motor goes bad on it.

 

[Omar_Eltahan]

It works fine, have tested it too.

 

[SHOZ]

Maybe the fan blade/cage on the blower is slipping? I would take the blower out and apply 12v directly too it and see what it does.

 

[SHOZ]

Some newer cars use solid state controllers for the fan speed output. When these go bad the fan becomes unresponsive to input commands. Is there a way to do a self test on the Climate Control system? Maybe something in your manual says how to do this.

 

[Omar_Eltahan]

I'll check.