According to the drying temperature range, it can be divided into four types.

1. Low temperature heat pump - a heat pump with a drying temperature between 10-45 degrees Celsius, which may be lower than the ambient temperature. In addition to heating up and drying, it may also need to cool down and dry. Low temperature heating is more suitable for open-loop machines, and closed-loop can also be achieved, but regardless of whether it is open-loop or closed-loop, the drying time is relatively long and the efficiency is low. Therefore, unless there are special requirements, low-temperature heat pumps are generally avoided as much as possible.

2. Medium temperature heat pump - a heat pump with a drying temperature between 45-65 degrees Celsius, where the drying temperature is higher than the ambient temperature. The temperature range of 45-65 degrees is the golden temperature for agricultural and seafood products. Basically, all agricultural and seafood products are suitable for drying in this temperature range, and the speed, quality, and efficiency can be optimized. Therefore, for food drying, it is advisable to consider or try using a medium temperature machine as much as possible.

3. High temperature heat pump - a heat pump with a drying temperature between 65-85 degrees Celsius. High temperature has a significant impact on the evaporation of water, and some agricultural, seafood, and industrial products require a certain level of high temperature to evaporate the bound water inside. Therefore, there is a high demand in the market.

4. Ultra high temperature heat pump - a heat pump with a drying temperature between 85-105 degrees, complex structure, expensive accessories, and high efficiency. Due to the need for high-temperature heat pumps to use refrigerants with high boiling points (above 40 degrees) such as R14 or R140, closed-loop heat pumps can only be used. A drying temperature close to 100 degrees Celsius can basically achieve flash drying, and the drying speed is very fast, but currently there are few drying products of this type on the market.