Crystal dry uses a heat exchanger for drying, so I guess that is what they are referring to. I guess you could try to claim that only the way HVAC's move heat around qualifies for being called a heat pump, not any other way of moving it should count right?
Here is what I got from Gemini:
Bosch does not refer to their dishwashers as having a "heat pump" in the same way the term is used for HVAC systems; rather, the part is often called a circulation motor and heating assembly or a combined "heater/pump" unit by users and repair sites. Bosch dishwashers use a flow-through water heater (a type of resistive element) to heat the water and a different, non-refrigerant-based system for drying. How the Bosch System Works
Water Heating: All Bosch dishwashers use a flow-through water heater, which is a heating element integrated with the circulation pump. This system rapidly increases the water temperature to the required level. It uses electrical resistance, not the reverse-refrigeration cycle of a true heat pump.
Drying: Bosch dishwashers (especially the higher-end models with features like CrystalDry) typically do not use a separate heating element for drying. Instead, they rely on a process involving a stainless steel tub and a heat exchanger or a mineral-based drying technology (like Zeolith for CrystalDry) to condense moisture and wick it away from the dishes. This is an energy-efficient method of moisture removal, not active heat generation for drying.
CrystalDry is an “upsell” feature on the high end versions of their dishwashers for more efficient drying. It’s not the thing that they’re calling a heat pump, that’s the water pump that also does resistive heating. Bottom line is, Bosch (nor anyone else afaik) does not make dishwashers that are more efficient due to using “heat pump” technology.
> I guess you could try to claim that only the way HVAC's move heat around qualifies for being called a heat pump, not any other way of moving it should count right?
Anything that moves heat from one area to another, not just evening them out but actually forcing the heat to move, counts as a heat pump. HVAC style, or peltier style, or other methods with tension or chemical reactions all count.
A combination heater and circulator does not do that. It is not a heat pump.