diff --git a/GHEtool/Validation/comparison_with_other_sizing_tools/test4/sensitivity_analysis.py b/GHEtool/Validation/comparison_with_other_sizing_tools/test4/sensitivity_analysis.py
index e6b44d85..54c53613 100644
--- a/GHEtool/Validation/comparison_with_other_sizing_tools/test4/sensitivity_analysis.py
+++ b/GHEtool/Validation/comparison_with_other_sizing_tools/test4/sensitivity_analysis.py
@@ -122,7 +122,7 @@ def test_4_sensitivity():
     ## Spacing 1 --S_1
     # 6 m 
     # initiate ground, fluid and pipe data
-    ground_data = GroundFluxTemperature(k_s=2.3, T_g=15, volumetric_heat_capacity=2052000, flux=0)
+    ground_data = GroundFluxTemperature(k_s=1.9, T_g=15, volumetric_heat_capacity=2052000, flux=0)
     fluid_data = FluidData(mfr=0.074*139.731/25, rho=1026, Cp=4019, mu=0.003377, k_f=0.468)
     pipe_data = MultipleUTube(r_in=0.013, r_out=0.0167, D_s=0.083/2, k_g=0.69, k_p=0.4)
 
@@ -167,7 +167,7 @@ def test_4_sensitivity():
     ## Spacing 2 --S_2
     # 10 m 
     # initiate ground, fluid and pipe data
-    ground_data = GroundFluxTemperature(k_s=2.3, T_g=15, volumetric_heat_capacity=2052000, flux=0)
+    ground_data = GroundFluxTemperature(k_s=1.9, T_g=15, volumetric_heat_capacity=2052000, flux=0)
     fluid_data = FluidData(mfr=0.074*139.731/25, rho=1026, Cp=4019, mu=0.003377, k_f=0.468)
     pipe_data = MultipleUTube(r_in=0.013, r_out=0.0167, D_s=0.083/2, k_g=0.69, k_p=0.4)
 
@@ -212,7 +212,7 @@ def test_4_sensitivity():
     ## Ground temperature 1 --GT_1
     # 10 C 
     # initiate ground, fluid and pipe data
-    ground_data = GroundFluxTemperature(k_s=2.3, T_g=10, volumetric_heat_capacity=2052000, flux=0)
+    ground_data = GroundFluxTemperature(k_s=1.9, T_g=10, volumetric_heat_capacity=2052000, flux=0)
     fluid_data = FluidData(mfr=0.074*139.731/25, rho=1026, Cp=4019, mu=0.003377, k_f=0.468)
     pipe_data = MultipleUTube(r_in=0.013, r_out=0.0167, D_s=0.083/2, k_g=0.69, k_p=0.4)
 
@@ -257,7 +257,7 @@ def test_4_sensitivity():
     ## Ground temperature 2 --GT_2
     # 20 C 
     # initiate ground, fluid and pipe data
-    ground_data = GroundFluxTemperature(k_s=2.3, T_g=20, volumetric_heat_capacity=2052000, flux=0)
+    ground_data = GroundFluxTemperature(k_s=1.9, T_g=20, volumetric_heat_capacity=2052000, flux=0)
     fluid_data = FluidData(mfr=0.074*139.731/25, rho=1026, Cp=4019, mu=0.003377, k_f=0.468)
     pipe_data = MultipleUTube(r_in=0.013, r_out=0.0167, D_s=0.083/2, k_g=0.69, k_p=0.4)
 
@@ -302,7 +302,7 @@ def test_4_sensitivity():
     ## Boreholes numbers 1 --BN_1
     # 3x3 bores
     # initiate ground, fluid and pipe data
-    ground_data = GroundFluxTemperature(k_s=2.3, T_g=20, volumetric_heat_capacity=2052000, flux=0)
+    ground_data = GroundFluxTemperature(k_s=1.9, T_g=20, volumetric_heat_capacity=2052000, flux=0)
     fluid_data = FluidData(mfr=0.074*139.731/25, rho=1026, Cp=4019, mu=0.003377, k_f=0.468)
     pipe_data = MultipleUTube(r_in=0.013, r_out=0.0167, D_s=0.083/2, k_g=0.69, k_p=0.4)
 
@@ -347,7 +347,7 @@ def test_4_sensitivity():
     ## Boreholes numbers 2 --BN_2
     # 7x7 bores
     # initiate ground, fluid and pipe data
-    ground_data = GroundFluxTemperature(k_s=2.3, T_g=20, volumetric_heat_capacity=2052000, flux=0)
+    ground_data = GroundFluxTemperature(k_s=1.9, T_g=20, volumetric_heat_capacity=2052000, flux=0)
     fluid_data = FluidData(mfr=0.074*139.731/25, rho=1026, Cp=4019, mu=0.003377, k_f=0.468)
     pipe_data = MultipleUTube(r_in=0.013, r_out=0.0167, D_s=0.083/2, k_g=0.69, k_p=0.4)