APTech KT12 - Manual (Page 5)

Operation Manual Piston Sensed Pressure Regulators
D. Manually Adjustable, Non-relieving (non-venting) Regulator Operation
Note: A pressure regulator should not be used as a positive shut-off device.
Caution: Do not pressurize the regulator low pressure port, except by rotating the adjustment wheel
clockwise (increasing the set point), as damage to the regulator internal parts or leakage may result.
1. Perform the following to increase the regulator delivery pressure set point.
a. Before opening the source valve, verify that the regulator adjustment wheel is turned fully
counterclockwise (fully decreased position).
b. Slowly open the source valve to pressurize the regulator high pressure port.
c. Rotate the regulator wheel clockwise to increase the delivery pressure to the desired pressure.
Note: The delivery pressure will decrease as the flow rate is increased. It may be
advantageous to compensate by adjusting the regulator to the desired delivery pressure while
operating at the desired flow conditions. Be aware the delivery pressure will rise if the flow
is shut-off or decreased downstream.
2. Perform the following to decrease the regulator delivery pressure set point for non-relieving
(non-venting) regulators.
a. Open a downstream valve to initiate a flowing condition.
b. Rotate the regulator wheel counterclockwise to reduce the delivery pressure below the
desired pressure.
c. Close the downstream valve to stop flow.
d. Rotate the regulator wheel clockwise to increase the delivery pressure to the desired pressure.
Note: The delivery pressure will decrease as the flow rate is increased. It may be
advantageous to compensate by adjusting the regulator to the desired delivery pressure while
operating at the desired flow conditions. Be aware the delivery pressure will rise if the flow
is shut-off or decreased downstream.
3. Perform the following to fully decrease the regulator delivery pressure.
a. Close the source valve.
b. Vent outlet to atmospheric pressure.
c. Rotate the regulator wheel fully counterclockwise.
E. Manually Adjustable, Self-relieving (self-venting) Regulator Operation
Note: A pressure regulator should not be used as a positive shut-off device.
Caution: Do not pressurize the regulator low pressure port, except by rotating the adjustment wheel
clockwise (increasing the set point), as damage to the regulator internal parts or leakage may result.
Caution: Self-relieving KT10 and KT12 regulators have a built in vent mechanism that vents the
delivery pressure through the cap into the atmosphere if the delivery pressure exceeds the set point.
Self-relieving KT10 and KT12 regulators should only be used with gases that can be safely released
in the area where the regulator is being used. The self-relieving mechanism incorporated into
AP Tech piston sensed regulators will come from the factory preset and should not need adjustment.
If any of the below conditions occur, then adjust the vent valve setting per section E.4.
 The regulator does not relieve its delivery pressure after several counterclockwise rotations
of the adjustment wheel.
 Audible venting is detected inside the regulator bonnet without rotating the adjustment
wheel.
Note: This condition may indicate a leak across the seat of the regulator. If adjusting the vent
valve according to section E.4 results in a steadily increasing outlet pressure or excessive
creep, then it is likely the regulator is leaking across the seat and needs to be repaired.
Page 5 of 9 Manual 15000011 Rev. 5