My AC dosen't blow the air hard?

Is this something that just started happening? Where is the air not blowing hard? Is it not blowing hard out of only one or two supply registers or is it not blowing hard out of all the supply registers? It could be the system is doing all it can do, especially if it's extremely hot outside. Also, it's possible there are dampers in the duct work that need adjusting, too. It's really hard to say what's going on with your system based on the little information you have provided. Your best bet is to have the system looked over by a reputable and knowledgeable HVAC contractor.

Sounds like you need to get the unit serviced an checked over but one unit for a 2 story house is always a bad idea. A return on the second floor would help some

My AC doesn't blow hard but it is designed that way. I have a two stage AC and most of the time it runs at the lower stage. By running at the lower level it is more effective at taking the humidity out of the air. If you don't have one already, I would look at getting your house zoned so you can heat and cool the floor independently. If your current system is older, it would be a good thing to do when you are replacing it. Be sure to get all of the available rebates and tax incentives.

You should make its every thing clean and check the gas in it

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