heating vs heating plant

heating and heating plant both are nouns.

Word	Noun	Adjective	Verb	Adverb
heating	Yes	No	No	No
heating plant	Yes	No	No	No

As nouns, heating and heating plant are synonyms defined as:

Other synonyms of heating include heat, heating system.

heating (noun)	heating plant (noun)
utility to warm a building	utility to warm a building
the process of becoming warmer; a rising temperature