there is a relay that turns on the radiator fan as soon as the ac is turned on, so tell your electrician to install that relay.
by using that relay, your radiator fan will be automatic w/o ac but when you will turn the ac on, fan will start. this relay system is fitted in all new cars by factory.
keep the fan automatic with thermostat valve, as it is good for engine.
in the summer, if the temperature needle exceeds halfway i.e 50 %, check your car with mechanic.