Heat exchanger tempering valve

A tempering valve for controlling a temperature of a fluid within a machine by dividing and proportioning flow of the fluid from the machine between a heat exchanger and a flow circuit that by-passes the heat exchanger, said tempering valve comprising:

• a valve body with inlet port for connection to an effluent line of the machine to facilitate receiving the fluid from the machine, an outlet port for connection to an influent line for the heat exchanger to enable discharging the received fluid to the heat exchanger, and a by-pass port for connection to an influent line of the machine for discharging the received fluid from the machine;
• a movable valve diverter positioned within said valve body, wherein the valve diverter is selectively positionable in at least three positions that create differing proportionate flow between the heat exchanger influent line and the by-pass port;
• an actuator device positioned within the valve body in mechanical contact with the valve diverter, the actuator device being configured to sense temperature of the received fluid and to actuator in response to the sensed temperature to position said valve diverter in one of the valve diverter positions;
• and
• means for manually throttling hydraulic resistance to flow of the fluid to the by-pass port and the by-pas flow circuit, the throttling means being positioned within the valve body upstream of he by-pass and outlet ports.