Best word for "maintenance"?
In testing sentences for "Wahrung" (the first word I found for "maintenance") I keep getting steered towards "Wartung", which is the more common or better word to use? For instance, if I wanted to say "I used to be a Maintenance Man." Or "That house needs some maintenance work." What would you use, and what's the difference?

Question

Answer

It depends as always on the context. If maintenance is used in the meaning of keep something going, you need to translate it with Wartung, Instandhaltung or Reparatur. Though there's also a difference. In connection with technical equipment and facilities we usually use Wartung. In connection with buildings we usually use Instandhaltung. 
An der Heizungsanlage sind Wartungsarbeitung notwendig.
Am Haus werden zurzeit Instandhaltungsarbeiten durchgeführt.
Reparatur works for both.

If maintenance is used in connection with rather non-material, ideological values which should be preserved for future generations we use Wahrung or Bewahrung.
Wahrung des kulturellen Erbes 
Wahrung der Freiheit 
Wahrung der Artenvielfalt 
Wahrung der Traditionen

Answer

Technical maintenance is "Wartung". So a "maintenance man" is a "Wartungstechniker" (other translations are possible).

"Wahrung" has nothing to do with technology, but more with non-material concepts, such as in: 
- "Wahrung des Gesichts" - saving face (as in many East Asian cultures)
- "Wahrung des xxx-Rechts" - observation of the law on xxx.
- "Wahrung der Menschenwürde" - preservation of human dignity

In which dictionary did you find "Wahrung" as the first word for "maintenance"?

Answer

Maintenance Man: Depending on the context Mechaniker, Hausmeister, Wartungsmonteur (https://dict.leo.org/englisch-deutsch/Maintenance%20Man)
Maintenance (work): As you see there are many translations. https://dict.leo.org/englisch-deutsch/Maintenance and https://dict.leo.org/englisch-deutsch/Maintenance%20work
For a house the most common would be: Instandhaltungsarbeiten, (laufende) Reparaturarbeiten, Ausbesserungsarbeiten;

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