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English
7. Operational Check
A visual inspection can be carried out to aid in determining the necessity for immediate
maintenance or repair, if the trap is open to atmosphere. If the trap does not discharge to
atmosphere, use diagnostic equipment such as TLV TrapMan or TLV Pocket TrapMan (within
their pressure and temperature measuring range).
(When conducting a visual inspection, flash steam is sometimes mistaken for steam leakage. For
this reason, the use of a steam trap diagnostic instrument such as TLV TrapMan is highly
recommended.)
Normal:
Condensate is discharged in a short blast followed by a longer period of no
drainage. During the discharge, flash steam may be seen. A small amount of flash
steam may be visible after the discharge.
Blocked:
(Discharge
Impossible)
No condensate is discharged. The trap is quiet and makes no noise. The surface
temperature of the trap is low.
Blowing:
Live steam continually flows from the outlet, and there is a continuous metallic
sound.
Steam
Leakage:
Live steam is discharged through the trap outlet together with condensate,
accompanied by a high-pitched sound.
Chattering:
The trap does not close properly. Steam is discharged from the trap in short rapid
bursts.
Flash Steam
Live Steam
Leakage
White jet
containing
water droplets
Clear, slightly
bluish jet
6. Piping Arrangement
Requirement
Diameter is too small.
Diameter is too small
and inlet protrudes
into pipe.
Rust and scale flow
into the trap with the
condensate.
Condensate collects
in the pipe.
Correct
Incorrect
Install a catchpot of the
proper diameter.
Make sure the flow of
condensate is not
obstructed.
To prevent rust and scale
from flowing into the trap,
connect the inlet pipe 25 -
50 mm (1 - 2 in) above the
base of the T-pipe.
When installing on the blind
end, make sure nothing
obstructs the flow of
condensate.
Check to make sure that the pipes connected to the trap have been installed properly.
1. Is the pipe diameter suitable, and has sufficient space been secured for maintenance?
2. Has the trap been installed with the arrow on the body pointing in the direction of flow?
3. Have maintenance valves been installed at the inlet and outlet? If the outlet is subject to
back pressure, has a check valve been installed?
4. Is the inlet pipe as short as possible, with as few bends as possible, and installed so that the
condensate will flow naturally down into the trap?
5. Has the piping work been done correctly, as shown in the table below?
