I do not know much about heating/cooling or even how to chose a service company. I used ABC once through a recommendation when doing a final walk through during the purchase of my first home. The A/C wasn't working and ABC came right out. 4 years later it was time to service my A/C again (just an old unit, nothing to do with their previous service) so I called them again and luckily they were able to come out same day. Great service, friendly technitian. I'd recommend ABC to everyone!
Changed out piston and cleaned out condenser... everything running great
Installed water heater and humidifier
Changing out run cap and charging unit with freon