Unitherm Heating Systems, a Dublin-based heat pump company, has been acquired by a Finnish heating and cooling systems firm which is ultimately owned by investment giant Apollo. The Irish company, which is 20 years in business this year, designs, supplies and services air-to-water heat pumps and ventilation systems, both for residential and commercial uses in Ireland and the UK. Its residential business includes private houses and apartments and large-scale developments as well as work with housing associations and local authorities. It also runs training programmes for installers and students. Purmo Group is a Helsinki-based firm building heating and cooling systems…