Abacus had corrected my 3yrs AC noise problem in 30mins. Many handymen couldn't fixed it over 3 yrs.
As it turned out: The main drain line ties into the plumbing of that sink. The main drain line coming off the unit in the attic into bathroom sink. Abacus installed two vents to stop the noise.
I was a very customer of Abacus.
I will use Abacus again & highly recommend them for AC and plumbing services.
Thank you Isaac Middleton for your excellent work!
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