Grow Gadgets 2KW Greenhouse HeaterKeep Grow Room Conditions Optimal During Colder Periods The Lighthouse 2KW Greenhouse Heater is a great way to help maintain constant temperatures during the difficult cooler months, creating even, radiated warmth for larger sized rooms and areas. While the heater helps greatly in the cooler months, it also doubles as an air circulator: you can set it to a 'no heat' option and just use the fan. There's also a 'half power' mode that heats the room at