Heating system for an automotive vehicle

A method of operating a heating system in a vehicle, the method comprising the steps of:

• (a) determining if a power plant is operating;
• (b) determining if a temperature of a coolant in a power plant coolant loop is above a predetermined temperature threshold;
• (c) when the temperature in the power plant coolant loop is not above the predetermined temperature threshold and the power plant is operating, actuating a valve to isolate a heater core coolant loop from the power plant coolant loop, activating a coolant pump in the heater core coolant loop and activating a coolant heater in the heater core coolant loop to heat the coolant in the heater core coolant loop before the coolant flows through a heater core in a first direction;
• and
• (d) actuating the valve to direct the coolant from the heater core coolant loop into the power plant coolant loop and the coolant from the power plant coolant loop into the heater core coolant loop and through the heater core in the first direction when the temperature in the power plant coolant loop is at or above the predetermined temperature threshold.