conference house vs conference center

conference house and conference center both are nouns.

Word	Noun	Adjective	Verb	Adverb
conference house	Yes	No	No	No
conference center	Yes	No	No	No

As nouns, conference house and conference center are synonyms defined as:

conference house and conference center: a center where conferences can be conducted

conference house (noun)	conference center (noun)
a center where conferences can be conducted	a center where conferences can be conducted