It is difficult to say which brand of residential air conditioning is the most reliable, as the reliability of an air conditioning system will depend on a variety of factors, including the quality of the equipment, the skill of the installation team, and the level of maintenance and care that the system receives. That being said, here are a few factors to consider when looking for a reliable air conditioning brand:

1. Reputation: Look for brands with a reputation for producing high-quality, reliable equipment. You can check online reviews and consumer organizations for information about the reliability of different brands.
2. Warranty: Look for brands that offer strong warranties on their equipment. This can help to protect you in case of any issues with the equipment and can give you peace of mind knowing that you are covered in the event of any problems.
3. Customer service: Consider the level of customer service that is offered by different brands. Look for brands that have a reputation for providing good customer service and are responsive to customer needs.
4. Energy efficiency: Energy efficiency is an important consideration when selecting a residential air conditioning system, as it can help to reduce energy costs and improve the overall efficiency of the system. Look for brands that offer energy-efficient equipment.

By considering these factors, you can help to ensure that you select a reliable brand of residential air conditioning. It is always a good idea to do your research and compare different brands to find the one that best meets your needs.