A new AC not cooling properly is usually due to installation errors — incorrect pipe length, insufficient gas charge, wrong tonnage, or poor indoor unit placement.
Data Verified: 2026Installation quality is critical. Common new AC installation errors: gas not filled to correct weight for the pipe length used, pipes bent at sharp angles reducing flow, indoor unit installed too high or aimed at a wall, or outdoor unit placed in a confined space without airflow.
Verify the AC is the correct tonnage for your room. A new 1 ton AC in a 200 sq ft room will never cool the room no matter how good the installation. Use our tonnage calculator to confirm sizing.
If you believe the installation is at fault, contact the dealer or installation team within the warranty period (typically 1 year on installation). They are obligated to fix installation defects at no charge. Document the issue with photos of the installation.
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My brand new AC is not cooling — is it defective?
Usually it is an installation issue, not a product defect. Check gas fill levels, pipe routing, and outdoor unit placement. Contact the installer within the warranty period for a free inspection.
Can wrong tonnage cause a new AC to not cool properly?
Yes. A new AC that is undersized for the room will never cool effectively, regardless of installation quality. Verify tonnage matches room size.
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