Question-and-Answer Resource for the Building Energy Modeling Community
 | 1 | initial version |
This error is saying that the temperature of the water coming into the cooling coil is too hot to provide cooling to the air. So when EnergyPlus opens the valve to increase the flow rate it doesn't provide more heating and the numerical solver fails.
My guess is that the controls for the water-side economizer aren't working correctly. Double-check the control type for the HX and all the setpoints and sizing variables for the water loops. Plot the supply outlet temperatures for both loops to see if/when they aren't providing cold enough water.
