 EaGa, ONE of the UK's biggest suppliers of heating and renewable energy services, has agreed to a ?306m takeover by the support services giant Carillion. Founded in 1990, Eaga employs about 4,000 people and is one of the UK's largest installers of central heating systems.  It provides emergency breakdown cover and servicing for 160,000 local authority and social housing properties, and works to lower carbon emissions and energy consumption, principally in low-income households.