Under the terms of the acquisition, CHN will also be integrated into E.ON's energy services division.
Don Leiper, the managing director of the division, said it was "a great deal" for the company as it looks to expand its business with a rapidly growing company.
He added: "We'll be able to utilise CHN's expertise to roll out the installation of the low carbon solutions, such as solar panels, thermal and ground source heat pumps we're developing as E.ON changes the way we look at energy in the UK."
E.ON's deal with CHN has come after it recently announced a new agreement with Energetix Group to develop and deploy new micro combined heat and power units.
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