pump house vs pumping station

pump house and pumping station both are nouns.

Word	Noun	Adjective	Verb	Adverb
pump house	Yes	No	No	No
pumping station	Yes	No	No	No

As nouns, pump house and pumping station are synonyms defined as:

pump house and pumping station: a house where pumps (e.g. to irrigate) are installed and operated

pump house (noun)	pumping station (noun)
a house where pumps (e.g. to irrigate) are installed and operated	a house where pumps (e.g. to irrigate) are installed and operated