A method of operating a vehicle climate system includes, by a controller, responsive to a same blower motor request, operating a blower motor at a first speed responsive to a heater core isolation valve (HCIV) directing coolant used to heat a cabin to an engine. The method further includes, by the controller, responsive to the same blower motor request, operating the blower motor at a second speed less than the first speed responsive to the HCIV directing the coolant to an electric heater and not to the engine.