Operating instructions

IM-P623-04 ST Issue 5
10
Maintenance note:
Maintenance can be completed with the trap in the pipeline, once the safety procedures
have been observed. It is recommended that new gaskets and spares are used whenever
maintenance is undertaken. Ensure that the correct tools and necessary protective
equipment are used at all times. When maintenance is complete open isolation valves
slowly and check for leaks.
6.1 Trap seat flushing during operation
This maintenance operation should be performed once every six months.
To clean the steam trap during operation, it is advisable to close the steam inlet valve
before turning the adjustment screw, and proceed as follows: (in a closed return system,
close the discharge line and open the test valve):
-
Remove the blind nut (11) and loosen the locking gland nut (6) by turning clockwise.
Note: the gland nut and adjustment screw have left hand threads.
-
Using a screwdriver, loosen the adjustment screw a few turns, clockwise. This completely
disengages the valve from the valve seat
(12).
-
Open the steam inlet valve slightly. This causes a strong purging action, which removes
any impurities that may have been deposited in the steam trap.
-
Turn the adjustment screw anticlockwise until the valve comes into contact with the valve
seat
(12). Turn through a further ¼ turn anticlockwise.
-
Retighten the locking gland nut (6) to the recommended torque (see Table 1, page 9) in
order to lock and reduce leakage past the adjustment screw.
-
Replace the blind nut (11) and gasket (10) and tighten to the recommended torque as
specified in Table 1, page 9.
-
Shut the test valve and open the discharge line valve and check for leaks.
-
Allow the trap to operate for several minutes and review the operation to ensure it is correct.
6.2 Trap discharge temperature adjustment
This procedure is the same as that given in Section 6.1. However, prior to re-tightening the
locking gland nut, the discharge temperature may be adjusted as follows:
-
To reduce by 10°C (50°F) (more subcooling), turn the screw anticlockwise ¼ turn.
-
To increase by 10°C (50°F) (less subcooling), turn the screw clockwise ¼ turn.
-
Allow trap operation and condensate temperature to stabilise between adjustments.
Continue adjusting until satisfactory operation is obtained.
6.3 Trap checking
In a closed return system, a test tee (see Figure 2) and valve must be used to observe
trap operation. The trap should modulate the condensate discharge depending on inlet
temperature and pressure.