6. Piping Arrangement
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? (Not required for FL5-C, FL21-C, FL32-C).
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?
Requirement
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.
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 Pocket TrapMan (within its
pressure and temperature measurement range).
Normal:
Blocked:
(Discharge Impossible)
Blowing:
Steam Leakage:
(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.)
Flash Steam
White jet
containing
water droplets
Correct
Condensate is discharged intermittently with flash steam and the
sound of flow can be heard.
No condensate is discharged. The trap is quiet and makes no noise.
The surface temperature of the trap is low.
Live steam continually flows from the outlet and there may be a high-
pitched whistling sound.
Live steam is discharged through the trap outlet together with the
condensate and there may be a high-pitched whistling sound.
― 10 ―
Incorrect
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.
Live Steam
Leakage
Clear, slightly
bluish jet