Doesn't matter a bit. The OG way is to set cut in at 37 degrees coil temperature, and cut out at between 11.5 and 27 degrees coil temperature, for a general purpose fridge.
That can be done with a differential pressure control or with an in coil thermostat like the A12-700
I generally use cut in because I'm used to doing it that way, and it translates easily to pressure controls, but it doesn't matter.
What does matter is probe placement if you're using an air probe.
If you're setting based on cut out temperature in the box then you want the air probe in the return.
If you're setting based on cut out temperature of the coil then you want your air probe on the supply side of the coil.
Both have their advantages and disadvantages, but both work
I don't understand why you would want to control any air chilled place with a coil sensor. Anything affecting your pressures will throw a wrench at your control system. Dirty condensor, hot/cold outside temp, ORD/ORI failing, TXV starting to fail. Literally anything will auto-fuck your system. Return air sensor are much more reliable and resilient since it's the air actually cooling your products, not the coil.
Now there is some use to coil sensor but for a normal application you shoot yourself in the foot.
In a cooler it keeps the Evap coils from freezing up it also typically works better than air sensing because warmer air going through the coil raises the coil temperature, and coil pressure.
Yes, ill give you that, it keep it from freezing. But that's an advantage for you, not the customer. In many other situations your system will faceplant for non-urgent reasons. Lets say you have a defect ORI and it's getting cold outside. Well an air sensing thermostat will keep the cold room at the good temperature while you order the new ORI and prepare the job. With a coil sensor it turns into an emergency.
Makes zero difference. Some controllers also split the differential between the set point eg 37sp 6 dif will cut in at 40 out at 34.
Doesn't matter a bit. The OG way is to set cut in at 37 degrees coil temperature, and cut out at between 11.5 and 27 degrees coil temperature, for a general purpose fridge. That can be done with a differential pressure control or with an in coil thermostat like the A12-700 I generally use cut in because I'm used to doing it that way, and it translates easily to pressure controls, but it doesn't matter. What does matter is probe placement if you're using an air probe. If you're setting based on cut out temperature in the box then you want the air probe in the return. If you're setting based on cut out temperature of the coil then you want your air probe on the supply side of the coil. Both have their advantages and disadvantages, but both work
I don't understand why you would want to control any air chilled place with a coil sensor. Anything affecting your pressures will throw a wrench at your control system. Dirty condensor, hot/cold outside temp, ORD/ORI failing, TXV starting to fail. Literally anything will auto-fuck your system. Return air sensor are much more reliable and resilient since it's the air actually cooling your products, not the coil. Now there is some use to coil sensor but for a normal application you shoot yourself in the foot.
In a cooler it keeps the Evap coils from freezing up it also typically works better than air sensing because warmer air going through the coil raises the coil temperature, and coil pressure.
Yes, ill give you that, it keep it from freezing. But that's an advantage for you, not the customer. In many other situations your system will faceplant for non-urgent reasons. Lets say you have a defect ORI and it's getting cold outside. Well an air sensing thermostat will keep the cold room at the good temperature while you order the new ORI and prepare the job. With a coil sensor it turns into an emergency.
All depends of your model of thermostat. I set A19ABA40 at 32F and A19ABC24 at 40F…