diff --git a/GsaGH/Helpers/GH/Legend/ContourLegend.cs b/GsaGH/Helpers/GH/Legend/ContourLegend.cs
index 90587268e..b12122327 100644
--- a/GsaGH/Helpers/GH/Legend/ContourLegend.cs
+++ b/GsaGH/Helpers/GH/Legend/ContourLegend.cs
@@ -11,14 +11,12 @@
 namespace GsaGH.Helpers.GH {
 
   internal class ContourLegend : IContourLegend {
-
     private const int DefaultTextHeight = 12;
     private const int DefaultBitmapWidth = 110;
     private readonly IContourLegendConfiguration _configuration;
-    private bool _isDrawLegendCalled = false;
     private int _leftBitmapEdge;
-
     private int _textHeight = DefaultTextHeight;
+    internal bool IsInvalidConfiguration = false; //only for tests
 
     public ContourLegend(IContourLegendConfiguration configuration) {
       _configuration = configuration;
@@ -31,10 +29,10 @@ public void DrawLegendRectangle(
       IGH_PreviewArgs args, string title, string bottomText,
       List<(int startY, int endY, Color gradientColor)> gradients) {
       if (!_configuration.IsLegendDisplayable()) {
+        IsInvalidConfiguration = true;
         return;
       }
 
-      _isDrawLegendCalled = true;
       InitializeDimensions(args.Viewport.Bounds.Right);
 
       // Step 1: Apply all gradients to the bitmap
@@ -47,8 +45,6 @@ public void DrawLegendRectangle(
       DrawTitle(args, title);
       DrawValues(args);
       DrawBottomText(args, bottomText);
-
-      _isDrawLegendCalled = false;
     }
 
     public void DrawGradientLegend(int startY, int endY, Color gradientColor) {
@@ -63,24 +59,21 @@ public void DrawGradientLegend(int startY, int endY, Color gradientColor) {
       }
     }
 
-    public void DrawBitmap(IGH_PreviewArgs args) {
-      EnsureDimensionsInitialized(args);
+    private void DrawBitmap(IGH_PreviewArgs args) {
       const int TopOffset = 20;
       int topPosition = CalculateScaledOffset(TopOffset);
 
       args.Display.DrawBitmap(new DisplayBitmap(_configuration.Bitmap), _leftBitmapEdge, topPosition);
     }
 
-    public void DrawTitle(IGH_PreviewArgs args, string title) {
-      EnsureDimensionsInitialized(args);
+    private void DrawTitle(IGH_PreviewArgs args, string title) {
       const int TopOffset = 7;
       int topPosition = CalculateScaledOffset(TopOffset);
 
       args.Display.Draw2dText(title, Color.Black, new Point2d(_leftBitmapEdge, topPosition), false, _textHeight);
     }
 
-    public void DrawValues(IGH_PreviewArgs args) {
-      EnsureDimensionsInitialized(args);
+    private void DrawValues(IGH_PreviewArgs args) {
       const int LeftOffset = 25;
       int leftEdge = _leftBitmapEdge + CalculateScaledOffset(LeftOffset);
       var zippedLists = _configuration.Values.Zip(_configuration.ValuePositionsY, (value, positionY) => new {
@@ -92,8 +85,7 @@ public void DrawValues(IGH_PreviewArgs args) {
       }
     }
 
-    public void DrawBottomText(IGH_PreviewArgs args, string bottomText) {
-      EnsureDimensionsInitialized(args);
+    private void DrawBottomText(IGH_PreviewArgs args, string bottomText) {
       const int BottomOffset = 145;
       const int ExtraOffset = 20;
       int bitmapWidth = CalculateScaledOffset(DefaultBitmapWidth);
@@ -109,15 +101,6 @@ private void InitializeDimensions(int viewportEdge) {
       _leftBitmapEdge = viewportEdge - CalculateScaledOffset(DefaultBitmapWidth);
     }
 
-    /// <summary>
-    ///   Ensures dimensions are initialized for individual drawing calls.
-    /// </summary>
-    private void EnsureDimensionsInitialized(IGH_PreviewArgs args) {
-      if (!_isDrawLegendCalled) {
-        InitializeDimensions(args.Viewport.Bounds.Right);
-      }
-    }
-
     private string WrapText(string bottomText, int width) {
       return TextWrapper.WrapText(bottomText, width, _textHeight);
     }
diff --git a/GsaGHTests/Helpers/GH/Legend/ContourLegendTests.cs b/GsaGHTests/Helpers/GH/Legend/ContourLegendTests.cs
index 6de929341..e185aac48 100644
--- a/GsaGHTests/Helpers/GH/Legend/ContourLegendTests.cs
+++ b/GsaGHTests/Helpers/GH/Legend/ContourLegendTests.cs
@@ -1,4 +1,8 @@
-using System.Drawing;
+using System;
+using System.Collections.Generic;
+using System.Drawing;
+
+using Grasshopper.Kernel;
 
 using GsaGH.Helpers;
 using GsaGH.Helpers.GH;
@@ -11,7 +15,7 @@ namespace GsaGHTests.Helpers {
   [Collection("GrasshopperFixture collection")]
   public class ContourLegendTests {
     private readonly Mock<IContourLegendConfiguration> _mockConfiguration;
-    private readonly ContourLegend legend;
+    private ContourLegend legend;
     private readonly Bitmap _mockBitmap;
 
     public ContourLegendTests() {
@@ -38,8 +42,33 @@ public void DrawGradientLegend_UpdatesBitmapCorrectly() {
         }
       }
     }
-    //other methods need to be tested manually or by integration tests. 
-    //we are not able to mock or inherit DisplayPipeline(which is needed to draw stuff)
-    //so we aren't able to check if drawings are correct
+
+    [Fact]
+    public void DrawGradientWillThrowErrorWhenStartValuesIsBiggerThanEndValue() {
+      Color color = Color.Red;
+      Assert.Throws<ArgumentOutOfRangeException>(() => legend.DrawGradientLegend(5, 1, color));
+    }
+
+    [Fact]
+    public void DrawGradientWillThrowErrorWhenEndValueIsBiggerThanBitmapHeight() {
+      Color color = Color.Red;
+      Assert.Throws<ArgumentOutOfRangeException>(() => legend.DrawGradientLegend(5, 200, color));
+    }
+
+    [Fact]
+    public void DrawGradientWillThrowErrorWhenStartValueLessThan0() {
+      Color color = Color.Green;
+      Assert.Throws<ArgumentOutOfRangeException>(() => legend.DrawGradientLegend(-1, 1, color));
+    }
+
+    [Fact]
+    public void ShouldNotDrawILegendIsNotDisplayable() {
+      legend = new ContourLegend(new ContourLegendConfiguration());
+      var previewArgsSpy = new Mock<IGH_PreviewArgs>();
+
+      legend.DrawLegendRectangle(previewArgsSpy.Object, string.Empty, string.Empty,
+        new List<(int startY, int endY, Color gradientColor)>());
+      Assert.True(legend.IsInvalidConfiguration);
+    }
   }
 }