Florida-based Carrier said on Tuesday it would buy the Viessmann business that makes heating boilers and heat pumps in a 12 billion euro ($13.2 billion) cash-and-stock deal.
Heat pumps play a key role in the German government's push to heat homes with renewable energy, part of larger ambitions to become carbon neutral by 2045.
Production capacity is set to be expanded by the deal, which would make heat pumps cheaper, Habeck said in Berlin.
Carrier is counting on an increase in demand as a result of the green push, saying in a statement that the heat pump market in Europe is set to triple to $15 billion by 2027.
The deal was given a cautious welcome by some politicians and associations, with Chancellor Olaf Scholz seeing it as a good thing, in principle, according to a spokesperson.
Britta Hasselmann, the Green party's leader in parliament, warned against a repeat of mistakes made in building up Germany's solar industry, which largely migrated to China after subsidies dried up.
The IG Metall union, which represents industrial sector workers in Europe's biggest economy, called for the government to tie subsidies, awards and public tenders to binding criteria that ensure investments stay in Germany.
($1 = 0.9022 euros)
(Reporting by Maria Martinez; Editing by Miranda Murray and Alexander Smith)
