Water Valves
Temperature regulation on IHKA systems is accomplished by solenoid actuated water valve(s). The valve(s) are normally held open by spring pressure (failsafe), and are electrically closed by pulses from the IHKA control module to regulate the flow of hot coolant to the heater core(s).
The water valve(s) are pulsed according to the Y-factor, which is calculated from the following inputs:
- Desired temperature request (left and right if equipped)
- Interior temperature
- Heater core temperature(s)
- Ambient air temperature
- Blower speed request
When the desired temperature calls for maximum heat, the water valve(s) do not receive pulses and are mechanically sprung open.
Similarly, when maximum cooling is requested, the IHKA control module powers the water valve(s) completely closed.