Hello,
Well, if you are unable to effectively change the speed of the air then your issue might be the blower motor or the blower switch.
Even if your A/C needs recharge, you still be able to increase/decrease the fan speed as normal. Only issue you would have is the temperature will not the ideal but the fan speed would be correct.
Do check your A/C to make sure it is fully charged, however if the issue does not change the blower fan is a good place to look. I have attached diagrams for your blower system.
Let me know of any questions.
Thank you.
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Monday, July 19th, 2021 AT 6:34 AM