Hello forum. Does anyone know a window or through-the-wall A/C with programmable temp differential? This sometimes is also called the temperature swing. Th room where I need to install such an A/C is quite small and there is a heat source, which raises the temp quickly. I want to be able to set some differential to reduce the power on cycles. Any brand or ideas?

I can consider rigging an A/C with some external thermostat (with temp differential) if this is reasonably easy.

Usually all a/c equiptment has a built in differential in the thermostat. They have to have this to prevent short cycle and destruction of the compressor over time. You can wire a thermostat in place of the built in one if you want more or different control settings.