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Hello community,

I've been working on modeling a walk-in freezer in EnergyPlus with a volume of 38 m3, utilizing a ThermostatSetpoint:SingleCooling set at -18°C with a 4 deltaC for Temperature Difference Between the Cutout and Setpoint. The simulation accurately reflects temperature fluctuations between -22°C and -18°C, as shown in the attached graph below, that present Air Zone Temperature, Compressor Electric Power, and Compressor Runtime Fraction.

However, I've observed an anomaly: when the compressor is not working (power = 0W), the runtime fraction is not equal to 0, which seems abnormal. The temperature rises when the compressor is shut down, but the runtime fraction persists. Any insights or suggestions on addressing this issue would be greatly appreciated!

Hello community,

I've been working on modeling a walk-in freezer in EnergyPlus with a volume of 38 m3, utilizing a ThermostatSetpoint:SingleCooling set at -18°C with a 4 deltaC for Temperature Difference Between the Cutout and Setpoint. The simulation accurately reflects temperature fluctuations between -22°C and -18°C, as shown in the attached graph below, that present Air Zone Temperature, Compressor Electric Power, and Compressor Runtime Fraction.

However, I've observed an anomaly: when the compressor is not working (power = 0W), the runtime fraction is not equal to 0, which seems abnormal. The temperature rises when the compressor is shut down, but the runtime fraction persists.

Any insights or suggestions on addressing this issue would be greatly appreciated!

Hello community,

I've been working on modeling a walk-in freezer in EnergyPlus with a volume of 38 m3, utilizing a ThermostatSetpoint:SingleCooling set at -18°C with a 4 deltaC for Temperature Difference Between the Cutout and Setpoint. The simulation accurately reflects temperature fluctuations between -22°C and -18°C, as shown in the attached graph below, that present Air Zone Temperature, Compressor Electric Power, and Compressor Runtime Fraction.

However, I've observed an anomaly: when the compressor is not working (power (Compressor Electric Power = 0W), the runtime fraction both Compressor Heat Transfer Rate and its Runtime Fraction is not equal to 0, which seems abnormal. The temperature rises when the compressor is shut down, but the runtime fraction persists. abnormal (the highlited parts in Fig.1 and 2 below).

Any insights or suggestions on addressing this issue would be greatly appreciated!

Fig.1

Fig.2

Hello community,

I've been working on modeling a walk-in freezer in EnergyPlus with a volume of 38 m3, utilizing a ThermostatSetpoint:SingleCooling set at -18°C with a 4 deltaC for Temperature Difference Between the Cutout and Setpoint. The simulation accurately reflects temperature fluctuations between -22°C and -18°C, as shown in the attached graph below, that present Air Zone Temperature, Compressor Electric Power, and Compressor Runtime Fraction.

However, I've observed an anomaly: when the compressor is not working (Compressor Electric Power = 0W), both Compressor Heat Transfer Rate and its Runtime Fraction is not equal to 0, which seems abnormal (the highlited parts in Fig.1 and 2 below).

Any insights or suggestions on addressing this issue would be greatly appreciated!

Fig.1

Fig.2

Hello community,

I've been working on modeling a walk-in freezer in EnergyPlus with a volume of 38 m3, utilizing a ThermostatSetpoint:SingleCooling set at -18°C with a 4 deltaC for Temperature Difference Between the Cutout and Setpoint. The simulation accurately reflects temperature fluctuations between -22°C and -18°C, as shown in the attached graph below, that present Air Zone Temperature, Compressor Electric Power, and Compressor Runtime Fraction.

However, I've observed an anomaly: when the compressor is not working (Compressor Electric Power = 0W), both Compressor Heat Transfer Rate and its Runtime Fraction is not equal to 0, which seems abnormal (the highlited parts in Fig.1 and 2 below).

It can be seen in the EXCEL table, between the timestep 0.08h and 0.22h the compressor is off but the Runtime Fraction in this period is equal to that of the last timestep (0.07h) and equals 0.82, and the same thing for the Compressor Heat Transfer it gives the capacity value of the last timestep.

Is this a bug in the code, or is there an explanation that I don't know?

Any insights or suggestions on addressing this issue would be greatly appreciated!

Fig.1

Fig.2