diff --git a/test/residual_test/residual_test.py b/test/residual_test/residual_test.py
index 6aa2e3faf239c9dc01b36245b2f0b208821973e8..0d952352bf18c17c0fe8c91ef2573946d6b31c47 100644
--- a/test/residual_test/residual_test.py
+++ b/test/residual_test/residual_test.py
@@ -99,3 +99,4 @@ def test_BOU_20200422():
         endtime=UTCDateTime("2020-04-23T00:00:00Z"),
     )
     assert_readings_equal(reading, calculate(reading), 0.1)
+    assert_readings_equal(reading, calculate(reading, False), 0.1)