Recent Review: After a regular tune-up of central AC, technician said a couple of parts might need to be replaced, but system was old (about 19 years) and used obsolete refrigerant, so I might consider replacement. Sila sent a project manager to review system. He spent about 45 minutes at house, taking measurements, talking to me about what I wanted, and suggesting options. They apparently deal exclusively with Lennox products. He gave me an estimate of a little over $10,000 for a new furnace, AC, and a bypass humidifier, which I hadn't had before. There was no hard sell; it felt like a professional presentation. (I got an estimate from another company. The guy spent about 15 minutes at the house, which didn't seem like enough time to consider what the house might need and what I was looking for in a major project. He sent an estimate that was a little lower, for American Standard products, but it wasn't exactly an apples-to-apples comparison. I didn't get the same professional vibe.) As I was still considering the offer from Sila and was close to deciding to use them, the project manager informed me they had an opening in the schedule for 2 days later and offered a bit of a discount if I took that date, so I accepted. The crew came at the appointed time and spent about 10 hours doing the installation. They had a professional attitude and tried to be as little disruptive as possible and cleaned up after themselves. The system has been working fine since then. The new AC is quieter than the old one and is supposed to be more energy efficient. The week after the installation they sent someone to check it out, check the refrigerant level, explain how things work, etc.