Heater cores transfer heat from the engine's cooling system to the inside of the vehicle. Thermostat housing and water outlets are connections that transfer coolant between the radiator and the engine block and generally house the thermostat.
7PP819810A HVAC Heater Control Valve,Heater Control Valve Compatible with Porsch
UAC HV 1212C HVAC Heater Control Valve -- Heater Control Valve
HVAC Heater Control Valve-Heater Valve 4 Seasons 74004 fits 94-99 Toyota Celica
HVAC Heater Control Valve-Heater Valve 4 Seasons 74628
HVAC Heater Control Valve-Heater Valve Cable UAC HV 1228C
HVAC Heater Control Valve-Heater Valve 4 Seasons 74646 fits 01-03 Toyota Sienna