Unitrol gas valves are part of a family of combination gas valves introduced to the market by Robertshaw in 1967. They are used to control gas flow in a variety of gas heating applications.
The first Unitrol gas valve was introduced in 1967 as part of the 7000 series. The Unitrol product line has evolved to offer 24-volt combination, 24-volt diaphragm, millivolt and line-voltage models, including hydraulic, two-stage manual and bleed operated products. Models are available for gas line capacities from 3/8 inch to 1 inch. Unitrol gas valves are widely-used and available from many sources including Amazon.com, Grainger and Zoro.