Abstract: A thermal input system is provided for a dishwasher having an interior wash chamber receiving soiled dishes and wash liquid. A heater is disposed in a sump region of the wash chamber along with a wash pump which operates to recirculate wash liquid through out the wash chamber. A soil collection chamber receives a portion of recirculating wash liquid from the wash pump wherein soils entrained in the wash liquid are captured within the soil collection chamber. A pressure sensor senses fluid pressure within the soil collection chamber. Control means are provided for energizing the heater during a thermal hold period in response to the pressure within the soil collector exceeding a predetermined limit pressure. In particular, the control means operates to sequence the dishwasher through a predetermined period of operation but bypasses the thermal hold cycle when the pressure within the soil collector does not exceed the predetermined limit pressure.