There are a lot of successful ways to force carb. For example, my process is transferring my room temp beer from the fermenter to the keg and then it goes into my kegerator which sits at 40. I set the pressure to 30psi for 48hrs and then move it down to serving temp for a week. This provides my brews perfect carbonation for me after a week and I've never overcarbed any of my brews. If you chill the keg first, you wouldn't need high pressure for as long due to the absorption rate of colder liquids and co2. Honestly, just play with different things and find out what works for you.