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Fail OpenBalanced PressureUp to 3.2 MPaG

TLV L21S Balanced Pressure Thermostatic Steam Trap

TLV L21S and L32S balanced pressure thermostatic steam traps feature a fail-open design and fixed subcooling. Suitable for tracer lines, dryers, and heaters up to 3.2 MPaG.

TLV L21S Balanced Pressure Thermostatic Steam Trap

TLV L21S and L32S are balanced pressure thermostatic steam traps with a "fail open" design. The L21SC and L32SC models include an internal check valve. They can be used without adjustment for medium capacity applications and pressures up to 2.1 or 3.2 MPaG (300 or 450 psig). These models are suitable for steam-using equipment that discharges condensate at temperatures slightly below saturation temperature, such as tracer lines and light process equipment.

Features

  • "Fail open" feature will not hold back condensate in the steam space.
  • Rugged, yet light construction, withstands superheat and water hammer.
  • Cyclic operation with fixed subcooling throughout the whole pressure range (up to 6 °C).
  • Outstanding air venting capability.
  • Compact, yet with high capacity.
  • Easy to clean and maintain.
  • Hardened stainless steel valve seat.
  • Built-in screen with large surface area.

WARNING

To avoid malfunctions, product damage, accidents or serious injury, install properly and DO NOT use this product outside the specification range. Local regulations may restrict the use of this product to below the conditions quoted.

Specifications

ModelL21S / L21SCL32S / L32SC
MaterialCarbon Steel / Stainless SteelCarbon Steel / Stainless Steel
ConnectionScrewed, Socket Welded, FlangedScrewed, Flanged
Size (mm)DN 15, 20, 25DN 15, 20, 25
Max. Operating Pressure (PMO)2.1 MPaG3.2 MPaG
Min. Operating Pressure0.01 MPaG0.01 MPaG
Maximum Back Pressure90% of inlet pressure90% of inlet pressure
Type of X-elementC6C6

Configuration

TLV L21S configuration and cross section

  1. Body
  2. Cover
  3. X-element
  4. Screen inside/outside
  5. Screen Holder Gasket
  6. Screen Holder
  7. Valve Seat
  8. X-element Guide
  9. Spring Clip
  10. Cover Gasket
  11. Cover Bolt
  12. Nameplate

TLV L21S exploded view

Discharge Capacity

TLV L21S discharge capacity graph

  1. Pressure differential is the difference between the inlet and outlet pressure of the trap.
  2. Recommended safety factor: at least 2.

Proper Installation

  1. Horizontal installation is recommended (with the cover facing upwards). Vertical installation is possible; however there may be a slight increase in the amount of steam leakage. Do not install in a reverse installation or sideways.
  2. Before installing the steam trap, blow out the inlet piping to remove all dirt and oil.
  3. Install a bypass valve, and inlet and outlet valves for maintenance or trap failure situations.
  4. Install the trap in the lowest part of the pipeline or equipment so the condensate flows into the trap by gravity.
  5. Install a check valve at the trap outlet of L21S, L32S whenever the condensate discharge pipe leads to a tank or recovery line.
  6. Support the pipes within 0.8 meters (2.5 ft) on either side of the trap.

Troubleshooting

ProblemCauseRemedy
No condensate is discharged (blocked) or discharge is poorX-element is stuck to the valve seatClean
Valve seat is cloggedClean
Screen is clogged with rust or scaleClean
Trap operating pressure exceeds maximum specified operating pressureStudy inlet pressure
Steam leakage or blow-offValve closure is obstructed by rust, etc.Clean (inspect screen as well)
X-element is worn or damagedReplace X-element
Valve seat is worn or damagedReplace valve seat or cover
Leakage from other locationCover is loose or gaskets are worn or damagedTighten cover or replace gasket