We had an issue with AC not cooling efficiently after the initial 21 pt checkup. This was late on Friday. Cool Air contacted me immediately and Irving scheduled a Saturday appointment. The tech ( Marcus, I believe ) was polite and knowledgeable, explained everything he was doing. I actually learned a few things. Seems issue was a loss of refrigerant which may have come during previous check, so the cause is undetermined. He charged the unit to proper levels and the AC is running great. And no charge to me for the Saturday visit, so the company went above and beyond, Highly recommend. : )