Warm-up apparatus for vehicle

A warm-up apparatus for a vehicle including a system which charges a battery by using an external power supply, the warm-up apparatus comprising:

• a heater for warming up, mounted in the vehicle, and configured to produce heat by receiving electric power from the external power supply;
• a current detector configured to determine an allowable current value that can be supplied to the vehicle by the external power supply and differs depending upon a specification of a charging equipment, based on a stored value which is stored in advance;
• a voltage detector configured to detect an output voltage value of the external power supply;
• and
• a resistance changer configured to change an electric resistance value of the heater based on the allowable current value detected by the current detector and the output voltage value detected by the voltage detector.