4
When installed in a pipeline, continuous flow past the sensing bulb must be maintained to obtain continuous
temperature signal to the regulator. If the flow stops, the pipeline may cool or warm to local room temperature
causing false reactions from the regulating valve. On some systems this may require a small by-pass flow line around
the valve to maintain representative system temperatures at the sensing bulb.
Sensing Bulb Installation
To install a union connected sensing bulb, remove the union hub or Thermowell from the sensing bulb and install this
hub or Thermowell into the process piping or tank. If using a Thermowell, liberally coat the sensing bulb with the
heat transfer paste supplied with the Thermowell. Now slip the sensing bulb through the hub or into the well until
fully seated. Tighten the coupling nut. Do not over tighten.
Never attempt to tighten, loosen or otherwise rotate the hub or Thermowell.
This will prevent twisting and kinking of the connecting tubing thus preventing premature failure.
Keep all bends in the tubing greater than 1-½” radius. Do not subject the tubing to repeated flexing, vibration, heat,
cutting, kinking or other abuse. Coil all excess tubing and place in a cool location. If motion or vibration may occur,
secure the tubing to the bulb mounting so all moves as one. If vibration or fluid pulsations may be transmitted to the
bulb, it must be housed in a Thermowell for protection from fatigue.
Placing The Regulator Into Operation And Setting The Control Point
Using the supplied ¼” rod, turn the 1-¾” adjusting screw to a position on the “0 to 8” reference scale that
approximately corresponds to the relative position of the desired control point within the adjustable range. The “V”
slot in the adjusting screw is intended as the index line for recording the setting number in maintenance logs. To
raise the control point, turn the adjusting screw from left to right up toward “HIGH” marked on the reference scale.
To lower the control point, turn the adjusting screw from right to left down toward “LOW” marked on the reference
scale. This adjustment must be done at system operation pressure to balance the stem thrust load for
proper regulation. (Refer to fig. 1 below)
DO NOT TURN THE SMALL HEX STEM JAM NUTS
This is a critical setting for the proper seating & stroke of the Regulator
CAUTION: DO NOT TURN THE SCREW BELOW THE “0” MARK
Figure 1
When the downstream units are ready to receive flow, close the by-pass valve and open all upstream supply valves
slowly to allow gradual start-up.
