panel heating vs heating

panel heating and heating both are nouns.

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

As nouns, heating is a hypernym of panel heating; that is, heating is a word with a broader meaning than panel heating:

panel heating: heating system consisting of wall or floor or baseboard or ceiling panels containing electric conductors or heating pipes
heating: utility to warm a building

Other hypernyms of panel heating include heat, heating plant, heating system.

panel heating (noun)	heating (noun)
heating system consisting of wall or floor or baseboard or ceiling panels containing electric conductors or heating pipes	utility to warm a building
	the process of becoming warmer; a rising temperature