diff --git a/Sources/ApiController/Extensions/Double+ensurePositive.swift b/Sources/ApiController/Extensions/Double+ensurePositive.swift
deleted file mode 100644
index a995b2d..0000000
--- a/Sources/ApiController/Extensions/Double+ensurePositive.swift
+++ /dev/null
@@ -1,9 +0,0 @@
-import Foundation
-
-extension Double {
-
-  func ensurePostive() -> Self {
-    if self < 0 { return self * -1 }
-    return self
-  }
-}
diff --git a/Sources/ApiController/Extensions/HVACSystemPerformance.swift b/Sources/ApiController/Extensions/HVACSystemPerformance.swift
index 33e7905..b8bee4f 100644
--- a/Sources/ApiController/Extensions/HVACSystemPerformance.swift
+++ b/Sources/ApiController/Extensions/HVACSystemPerformance.swift
@@ -85,8 +85,4 @@ public extension HVACSystemPerformance.Request {
       throw ValidationError(message: "System size should be greater than 0.")
     }
   }
-
-  struct ValidationError: Error {
-    let message: String
-  }
 }