A unit of British technology and controls corporation Invensys PLC, Robertshaw Controls Co. has two distinct divisions. The industrial products unit encompasses level controls, vibration monitors and switches, control valves, regulators, and wireless level monitoring technologies. For HVAC products, Robertshaw is devoted almost exclusively to thermostats in a variety of setups, though it offers products including humidistats and air cleaners.
Siebe PLC, a company formed in 1819, acquired Robertshaw in 1986, adding the company's thermostat offerings as it converted from a local domestic safety products company to a more globally focused controls operation. At the time, Robertshaw's specialty category was appliances, a segment Siebe lacked a position in. One of North American's largest appliance controls companies at the time, the Robertshaw acquisition would let Siebe venture deeper into appliance controls, acquiring Ranco and Barber-Colman the year after the Robertshaw purchase. With these acquisitions, Siebe entered the industrial and commercial building control systems industry, as well as automotive control systems. In 1999, Siebe merged with British manufacturing conglomerate BTR, the combined company becoming Invensys. In the time since, Robertshaw has become focused on thermostats as part of Invensys Controls, whose overall lines include thermostats, valves, zone controls, timers, and electronic components under a variety of brand names.
Robertshaw makes a wide array of thermostats ranging from mechanical thermostats, such as its 9200 series; programmable thermostats in 300, 8600, 9600, 9700, 9800 and 9900 series; nonprogrammable thermostats in its 300, 8400, 9400 and 9500 series; and its 800 series line voltage thermostats. All except the line voltage products come in value and deluxe specifications.
Robertshaw's thermostats come with varying warranties, depending on the model. For example, the deluxe 9920i programmable thermostat has a two-year backing, while the 9610 comes with a five-year warranty. The 9200 series mechanical thermostat comes with a one-year warranty.