Updated warning message and test.

Author: tanaya-mankad

src/EnergyPlus/VariableSpeedCoils.cc

@@ -4749,16 +4749,20 @@ namespace VariableSpeedCoils {
                         TotCapTempModFac =
                             Curve::CurveValue(state, varSpeedCoil.MSCCapFTemp(varSpeedCoil.NormSpedLevel), MixWetBulb, RatedSourceTempCool);
 
-                        if (MixEnth > SupEnth) {
-                            CoolCapAtPeak = (rhoair * VolFlowRate * (MixEnth - SupEnth)) + FanCoolLoad;
-                        } else {
-                            CoolCapAtPeak = (rhoair * VolFlowRate * (48000.0 - SupEnth)) + FanCoolLoad;
-                        }
-                        if ((CoolCapAtPeak < 0) && (MixTemp < SupTemp)) {
+                        CoolCapAtPeak = (rhoair * VolFlowRate * (MixEnth - SupEnth)) + FanCoolLoad;
+                        if (CoolCapAtPeak < 0) { // This conditional will also catch the initialization value, -999.0
                             ShowWarningError(
                                 state,
-                                format("On design day {}, cooling coil entering air temperature {:.2R} is less than design supply air temperature {:.2R}. This would "
-                                "yield negative coil capacity sizing for {}.", state.dataSize->FinalSysSizing(state.dataSize->CurSysNum).CoolDesDay, MixTemp, SupTemp, varSpeedCoil.Name));
+                                format(
+                                    "In calculating capacity for coil {} on design day {}, the air state would yield negative coil capacity sizing.",
+                                    varSpeedCoil.Name,
+                                    state.dataSize->FinalSysSizing(state.dataSize->CurSysNum).CoolDesDay));
+                            ShowContinueError(state, format("The air properties are: T_mix = {:.4R}", MixTemp));
+                            ShowContinueError(state, format("                        T_supply = {:.4R}", SupTemp));
+                            ShowContinueError(state, format("                        H_mix = {:.4R}", MixEnth));
+                            ShowContinueError(state, format("                        H_supply = {:.4R}", SupEnth));
+                            ShowContinueError(state, format("                        W_mix = {:.4R}", MixHumRat));
+                            ShowContinueError(state, format("                        W_supply = {:.4R}", SupHumRat));
                             ShowContinueError(state, "Cooling capacity is set to zero during sizing; simulation continues.");
                         }
                         CoolCapAtPeak = max(0.0, CoolCapAtPeak);

tst/EnergyPlus/unit/UnitarySystem.unit.cc

@@ -6767,7 +6767,7 @@ TEST_F(EnergyPlusFixture, VSCoilUnitary_NoNegativeCapacity)
     Real64 constexpr SpeedRatio{0.0};
     int constexpr SpeedCal{1};
     VariableSpeedCoils::InitVarSpeedCoil(*state, DXCoilNum, SensLoad, LatentLoad, fanOp, OnOffAirFlowRatio, SpeedRatio, SpeedCal);
-    EXPECT_TRUE(compare_err_stream_substring("This will yield negative coil capacity sizing", true));
+    EXPECT_TRUE(compare_err_stream_substring("the air state would yield negative coil capacity sizing", true));
     // Cooling design day name should be populated, but is not. This appears to be a separate issue that should be addressed at a later time.
     // EXPECT_TRUE(compare_err_stream_substring("Annual Cooling 1 %", true));
 }