1) direct the fan of radiator direct
2) add coolant (pink coolant).
as green coolant is less powerful.
coolant is anti-heating, anti-freezing and anti-rust.
your heat level will be 40% drop as the radiation of water will not be heated.
if your radiator is in good condition, i.e. it doesn't has any rust in it, then add as much coolant you want. but do not full the radiator with coolant if the radiator is rusted. to full the radiator with coolant you should get your radiator get serviced.
and then ask the radiator mechanic if your radiator is weak!.
if it is good then fill coolant as much you want.