Self-Operated, No External Power Source The Mark 80 Series is completely self-operated and requires no external power source or other expensive instrumentation to operate the valve. Depending on valve action, the seats open or close as bulb senses rise in temperature. The Mark 80 has high rangeability - controls flows from 10% to 90% of rated capacity. Available with up to 100 feet (30 meters) in capillaries.

Self-Operated, High Flow The Mark 801/802 Series is completely self-operated and requires no external power source or other expensive instrumentation to operate the valve. The Mark 801/802 Series are high-flow versions of our Mark 80 Series temperature regulators. Available with up to 100 feet (30 meters) in capillaries.

Internal Piloted Temperature Regulators

Controlled Failure Option The Mark 85 Series is a self-operated temperature regulator with controlled failure option which allows you to predetermine the position of the valve in the event of a thermal system failure. The Mark 85 is designed to fail closed on heating applications and to fail open on cooling applications. The Mark 85 Series is ideal for slower responding systems such as autoclaves and large storage tanks.

Ambient Temperature The Mark 86 regulator is designed to control steam tracing lines based on ambient temperatures. The MK86 allows steam to flow through the tracer lines only when it is needed, then opens or closes when ambient temperature rises above or below the setpoint depending on action.

Externally Piloted The Mark 87 piloted temperature regulator is the sliding gate valve engineered to provide wide rangeability, and greater accuracy, for a variety of temperature control applications. Designed with the same technology as the Mark 80, the Mark 87 is a piloted temperature regulator that offers quality and performance. It can be used where larger line sizes and higher flow rates are required.

Three-Way, Diverting or Mixing Service The Mark 89 is used for diverting service and is ideal for bypassing fluids around coolers or filters. In this configuration, there is one inlet and two outlets. As one outlet closes, the other outlet opens, diverting flow from one channel to the other. The Mark 89MX is ideal for mixing service.