Question-and-Answer Resource for the Building Energy Modeling Community
 | 1 | initial version |
I think you actually want to put a max PLR greater than 1. Perhaps 1.2 or so.
If you read the Engineering Reference for Electric Chiller Model Based on Condenser Entering Temperature, you'll see that it is actively being limited to the max PLR you define:
The part-load ratio is then calculated as the ratio of the evaporator heat transfer rate to the available chiller capacity. The part-load ratio is not allowed to be greater than the maximum part-load ratio specified by the user or less than zero as follows:
$$PLR = \max{(0.0, \min (\frac{\dot{Q}_{evap}}{\dot{Q}_{avail}},PLR_{max}))}$$
| | 2 | No.2 Revision |
I think you actually want to put a max PLR greater than 1. Perhaps 1.2 or so.
If you read the Engineering Reference for Electric Chiller Model Based on Condenser Entering Temperature, you'll see that it is actively being limited to the max PLR you define:
The part-load ratio is then calculated as the ratio of the evaporator heat transfer rate to the available chiller capacity. The part-load ratio is not allowed to be greater than the maximum part-load ratio specified by the user or less than zero as follows:
$$PLR = \max{(0.0, \min (\frac{\dot{Q}_{evap}}{\dot{Q}_{avail}},PLR_{max}))}$$
Interestingly, looking at the IDF example files briefly, I couldn't find a chiller with a PLR greater than 1, though 1.1 or 1.2 is often used for Boiler:HotWater.
