diff --git a/app/api/files/PDF.ts b/app/api/files/PDF.ts
index 4a2c454133..d1620fdcfa 100644
--- a/app/api/files/PDF.ts
+++ b/app/api/files/PDF.ts
@@ -85,7 +85,7 @@ class PDF extends EventEmitter {
       ...conversion,
       ...this.file,
       language:
-        detectLanguage(Object.values(conversion.fullTextWithoutPages).join(''), 'franc') ||
+        detectLanguage(Object.values(conversion.fullTextWithoutPages).join(''), 'ISO639_3') ||
         undefined,
       processed: true,
       toc: [],
diff --git a/app/shared/detectLanguage.ts b/app/shared/detectLanguage.ts
index 18678ea89e..025bc08084 100644
--- a/app/shared/detectLanguage.ts
+++ b/app/shared/detectLanguage.ts
@@ -1,6 +1,6 @@
 import franc from 'franc';
-import { language } from 'shared/languagesList';
+import { language, LanguageCode } from 'shared/languagesList';
 
-const detectLanguage = (text: string, purpose: 'elastic' | 'franc' | 'ISO639_1' = 'elastic') =>
+const detectLanguage = (text: string, purpose: LanguageCode = 'elastic') =>
   language(franc(text), purpose);
 export { detectLanguage };
diff --git a/app/shared/languagesList.ts b/app/shared/languagesList.ts
index ad07bc7940..aa6f1804d7 100644
--- a/app/shared/languagesList.ts
+++ b/app/shared/languagesList.ts
@@ -1,7 +1,7 @@
 /* eslint-disable max-lines */
 import { LanguageSchema } from 'shared/types/commonTypes';
 
-type LanguageCode = 'elastic' | 'ISO639_3' | 'ISO639_1' | 'franc';
+type LanguageCode = 'elastic' | 'ISO639_3' | 'ISO639_1';
 
 type LegacyElasticObject = Record<
   string,
diff --git a/app/shared/specs/languages.spec.js b/app/shared/specs/languages.spec.js
index 97acbb591f..73cb65f749 100644
--- a/app/shared/specs/languages.spec.js
+++ b/app/shared/specs/languages.spec.js
@@ -50,10 +50,14 @@ describe('languages', () => {
       expect(detectLanguage('what is the colour of the white horse of santiago', 'ISO639_1')).toBe(
         'en'
       );
-      expect(detectLanguage('de que color es el caballo blanco de santiago', 'franc')).toBe('spa');
-      expect(detectLanguage('what is the colour of the white horse of santiago', 'franc')).toBe(
+      expect(detectLanguage('de que color es el caballo blanco de santiago', 'ISO639_3')).toBe(
+        'spa'
+      );
+      expect(detectLanguage('what is the colour of the white horse of santiago', 'ISO639_3')).toBe(
         'eng'
       );
+
+      expect(detectLanguage('Це перевірка', 'ISO639_3')).toBe('ukr');
     });
 
     it('should return other when the language is not supported', () => {