The heat pump type low-temperature evaporator cannot manually input kilowatts to adjust power like electric heating, but can achieve heating output capacity adjustment in two ways: fixed frequency and variable frequency models.

1. Fixed frequency compressor (common low-end models on the market, accounting for the majority)

The compressor has only two gears: fully open/stop, and the power cannot be continuously and continuously adjusted.

PLC temperature control based on start stop duty cycle: the compressor starts at full power when the temperature is low; When the set evaporation temperature is reached, the compressor stops. By starting and stopping, the equivalent average heating power changes.

Disadvantages: Large fluctuations in environmental temperature (especially in winter), and larger temperature fluctuations in incoming materials; Frequent start stop when the load is low.

Main electric heating (pipeline tank anti freezing): This part of the electric heating power is mostly controlled by on-off, and a few models support thyristor power adjustment.

2. Variable frequency compressor (high-end model)

The compressor frequency can be continuously adjusted, and the heating output power can be infinitely adjusted.

The PLC automatically changes the operating frequency of the compressor based on the temperature of the feed liquid, ambient temperature, and vacuum degree, and the output heat can be continuously adjusted from 30% to 100%.

Advantages: In winter, when the incoming material temperature is low and the amount of wastewater feed fluctuates, the heating output is automatically raised; When the load is low, reduce frequency and start stop, resulting in more stable temperature and lower energy consumption.

Note: This is only for adjusting the heating capacity output, not manually inputting values such as "5kW, 8kW" on the screen. Generally, the evaporation temperature is set and the equipment automatically matches the power.

3. Key points for practical selection (combined with previous winter working conditions)

Northern/outdoor winter working conditions, priority should be given to variable frequency heat pump models, which can automatically increase heating output in low temperature environments with less evaporation attenuation. Fixed frequency models can only rely on repeated start stop in winter, and the evaporation rate will significantly decrease.

Don't expect manual locking of heating power; The device sets the evaporation temperature and the system automatically matches the output power.

The additional tank and pipeline antifreeze heating belong to auxiliary heating and not to the main evaporative heating system.