Question-and-Answer Resource for the Building Energy Modeling Community
 | 1 | initial version |
I figured out the cause by comparing my model and HVACTemplate-5ZoneVRF.idf in ExampleFiles.
The cause was Maximum Outdoor Temperature in Heating Mode in HVACTemplate:System:VRF. The default value is 16ºC. However, if a value that is less than 26.5ºC is input, the WaterCooled VRF doesn't heat zones even when the actual outdoor temperature is much lower than the input value. This might be a bug.
This does not occur when AirCooled is selected as Condenser Type of VRF. The value in HVACTemplate-5ZoneVRF.idf is set to 30ºC (below image), and it runs fine. My model used default 16ºC.
| | 2 | No.2 Revision |
I figured out the cause by comparing my model and HVACTemplate-5ZoneVRF.idf in ExampleFiles.
The cause was Maximum Outdoor Temperature in Heating Mode in HVACTemplate:System:VRF. The default value is 16ºC. However, if a value that is less than 26.5ºC is input, the WaterCooled VRF doesn't heat zones even when the actual outdoor temperature is much lower than the input value. This might be a bug.
This does not occur when AirCooled is selected as Condenser Type of VRF. The value is set to 30ºC in HVACTemplate-5ZoneVRF.idf is set to 30ºC (below image), and it runs fine. My model used default 16ºC.
| | 3 | No.3 Revision |
I figured out the cause by comparing my model and HVACTemplate-5ZoneVRF.idf in ExampleFiles.
The cause was Maximum Outdoor Temperature in Heating Mode in HVACTemplate:System:VRF. The default value is 16ºC. However, if a value that is less than 26.5ºC is input, the WaterCooled VRF doesn't heat zones even when the actual outdoor temperature is much lower than the input value. This might be a bug.
This does not occur when AirCooled is selected as Condenser Type of VRF. The value is set to 30ºC in HVACTemplate-5ZoneVRF.idf (below image), and it runs fine. My model used default 16ºC.16ºC. When I changed it to 26.5°C or higher, my model started to heat zones in winter.
| | 4 | No.4 Revision |
I figured out the cause by comparing my model and HVACTemplate-5ZoneVRF.idf in ExampleFiles.
The cause was Maximum Outdoor Temperature in Heating Mode in HVACTemplate:System:VRF. The default value is 16ºC. However, if a value that is less than 26.5ºC is input, the WaterCooled VRF doesn't heat zones even when the actual outdoor temperature is much lower than the input value. This might be a bug.
This does not occur when AirCooled is selected as Condenser Type of VRF. The value is set to 30ºC in HVACTemplate-5ZoneVRF.idf (below image), and it runs fine. My model used default 16ºC. When I changed it to 26.5°C 26.5ºC or higher, my model started to heat zones in winter.winter. Conversely, when I changed the value to less than 26.5ºC in HVACTemplate-5ZoneVRF.idf, the model stopped heating.
