gas system vs installation

gas system and installation both are nouns.

Word	Noun	Adjective	Verb	Adverb
gas system	Yes	No	No	No
installation	Yes	No	No	No

As nouns, installation is a hypernym of gas system; that is, installation is a word with a broader meaning than gas system:

gas system: facility (plant and equipment) for providing natural-gas service
installation: a building or place that provides a particular service or is used for a particular industry

Other hypernyms of gas system include facility.

gas system (noun)	installation (noun)
facility (plant and equipment) for providing natural-gas service	the act of installing something (as equipment)
	a building or place that provides a particular service or is used for a particular industry
	a formal entry into an organization or position or office