pump house vs pump room

pump house and pump room both are nouns.

Word	Noun	Adjective	Verb	Adverb
pump house	Yes	No	No	No
pump room	Yes	No	No	No

As nouns, pump room is a hyponym of pump house; that is, pump room is a word with a more specific, narrower meaning than pump house:

pump house: a house where pumps (e.g. to irrigate) are installed and operated
pump room: a pump house at a spa where medicinal waters are pumped and where patrons gather

pump house (noun)	pump room (noun)
a house where pumps (e.g. to irrigate) are installed and operated	a pump house at a spa where medicinal waters are pumped and where patrons gather