DELTA i-system polar white room temperature controller for underfloor heating Our extensive DELTA product range offers you a wealth of individual design options thanks to its stylish variety of shapes and colors, which skilfully underline the aesthetics of every room. The DELTA electronic devices for installation technology offer extensive additional functions such as dimmers for all common loads including LED lighting, motion detectors in surface and flush-mounted versions, blind controls, timers or room temperature controls. DELTA switches and sockets - design and quality in perfection from Siemens.