PlantEquipmentOperation:OutdoorDryBulb

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Hello, I'm a design builder user so hopefully you can extract the E+ objects from the following description:

When setting up a loop like this, I connect the W2AHP in series with the boiler. The W2AHP is first in line. In the Plant Equipment Operation, Scheme, heating load, I select the equipment (heat pump and boiler) and set the priority, with the heat pump as priority 1. This configuration allows the heat pump to provide as much heating as capacity allows and the boiler will add to meet the plant loop temperature setpoint. You can set the -10C minimum outdoor air temperature for heating in the object of the heat pump.

I think this post shows a incorrect behavior on the EnergyPlus code. Here is the link to the line of code that gets that particular error: E+ Github Condenser Loop Operation

The code for the lower limits of PlantEquipmentOperation have different values in terms of errors: Heating/Cooling Load or relative humidity cannot have a lower limit below 0, but others (such as OutdorDrybulb) are allowed to have a lower range down to -70oC.

Yet the upper range is limited to "cannot be negative" for ALL operation schemes. I cannot think of a reason to do so other than an oversight. I have created an issue in the E+Github linked to this post: Issue link

The proposed solution of priorities in Design Builder is not even an exact equivalent because the boiler will work at any outside temperature, even if this is "adequate" or "realistic", the bad behavior on the side of the code remains.