The TLV LV21 is an all-stainless steel balanced pressure thermostatic steam trap designed for applications where the condensate load is relatively small, such as tracing lines, vessels, and heaters. It features a revolutionary "fail open" design and utilizes a high-performance X-element that responds highly sensitively to temperature changes, discharging air and large quantities of condensate immediately upon startup to significantly reduce startup time.

Preferably installed vertically, the LV21 offers a rugged yet light construction capable of withstanding superheat and water hammer. Its cyclic operation maintains fixed subcooling throughout the entire pressure range, ensuring outstanding air venting capability and preventing air binding.

Features

1. "Fail open" feature: Designed to fail in the open position to prevent condensate backup.
2. Rugged construction: Light yet durable, withstanding superheat and water hammer.
3. Cyclic operation: Fixed subcooling throughout the entire pressure range.
4. Outstanding air venting: Highly sensitive to hot air inflow, preventing air binding.
5. Compact and high capacity: Small footprint with excellent discharge performance.
6. Easy maintenance: Simple to maintain and clean.
7. Hardened valve surfaces: Stainless steel valve surfaces for extended service life.
8. Built-in screen: Features a large surface area to protect internal components.

Specifications

Parameter	Value
Connection	Screwed (BSP DIN 2999, other standards available)
Size	1/4", 3/8", 1/2"
Max. Operating Pressure (PMO)	21 barg (2.1 MPaG)
Min. Operating Pressure	0.1 barg (0.01 MPaG)
Maximum Back Pressure	90% of Inlet Pressure
Subcooling of X-element Fill	up to 6 °C (option: up to 22 °C)
Type of X-element	C6 (option: C22)

PRESSURE SHELL DESIGN CONDITIONS

Maximum Allowable Pressure (PMA): 63 barg (6.3 MPaG) Maximum Allowable Temperature (TMA): 425 °C Minimum Allowable Temperature: -40 °C These are design conditions, NOT operating conditions. Do not use this product outside of the specification range.

Materials

No.	Description	Material	DIN*	ASTM/AISI*
①	Body Upper Part	Cast Stainless Steel A351/A351M Gr.CF8 or CF8M	1.4312 or 1.4410	-
②	Body Lower Part	Cast Stainless Steel A351/A351M Gr.CF8 or CF8M	1.4312 or 1.4410	-
③	X-element	Stainless Steel	-	-
④	Valve Seat	Stainless Steel SUS630	1.4542	AISI630
⑤	Screen	Stainless Steel SUS304	1.4301	AISI304
⑥	Nameplate	Stainless Steel SUS304/SUS316L	1.4301/1.4404	AISI304/AISI316L
⑦	Spring Clip	Stainless Steel SUS304	1.4301	AISI304

*Equivalent materials

Dimensions and Weight

Size	L (mm)	φW (mm)	Weight (kg)
1/4"	55	47	0.4
3/8"	55	47	0.4
1/2"	55	47	0.4

Discharge Capacity

Capacity Notes

1. Differential pressure is the difference between the inlet and outlet pressure of the trap.
2. Recommended safety factor: 2.

Installation and Piping

Safety Considerations

Take measures to prevent people from coming into direct contact with product outlets. Failure to do so may result in burns or other injury from the discharge of fluids.

1. Before installation, be sure to remove all protective seals from the product.
2. The LV21 can be installed vertically or horizontally. If installed vertically, ensure the inlet side is at the top. There may be a slight increase in the amount of steam leakage when installed horizontally.
3. Before installing the steam trap, blow out the inlet piping to remove all dirt and oil.
4. Install a bypass valve to discharge condensate, and inlet and outlet valves to isolate the trap in the event of trap failure or when carrying out maintenance.
5. Install the trap in the lowest part of the pipeline or equipment so the condensate flows naturally downward into the trap by gravity. The inlet pipe should be as short and have as few bends as possible.
6. Install a check valve at the trap outlet whenever the condensate discharge pipe leads to a tank or recovery line, or whenever the condensate collection pipeline is connected to more than one trap.
7. In order to avoid excessive back pressure, make sure the discharge pipes are large enough (the outlet back pressure allowance should be no more than 90% of the inlet steam pressure).

Inspection and Maintenance

Operational inspections should be performed at least twice per year, or as called for by trap operating conditions. Faulty steam traps may result in losses due to steam leakage.

WARNING

Before attempting to open the trap, close the inlet and outlet isolation valves and wait until the trap has cooled to room temperature. Failure to do so may result in burns or injury.

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.

• Normal: Condensate is discharged intermittently with flash steam and the sound of flow can be heard.
• Blocked: 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 may be a high-pitched whistling sound.
• Steam Leakage: Live steam is discharged through the trap outlet together with the condensate and there may be a high-pitched whistling sound.

Disassembly and Reassembly

Part	Disassembly	Reassembly
Cover	Use an open-end wrench to remove	Clean seating surfaces; coat threaded portions with anti-seize; tighten to 120 N·m (88 lbf·ft)
Spring Clip	Use pliers to remove	Insert securely into the 3 slots in the guide or cover
X-element	Use pliers to grasp the ball at the tip of the element and remove	Insert with right side up; make sure it does not catch on guide or cover
Screen	Be careful not to bend the screen	Be careful not to bend the screen

Troubleshooting

If the expected performance is unachievable after installation, check the following:

Problem	Cause	Remedy
No condensate is discharged (blocked) or discharge is poor	X-element is stuck to the valve seat	Clean
	Valve seat is clogged	Clean
	Screen is clogged with rust or scale	Clean
	Steam-locking has occurred	Perform a bypass blowdown, or close the trap inlet valve and allow the trap to cool. Piping correction may also be required.
	Trap operating pressure exceeds maximum specified operating pressure	Study inlet pressure
	Differential pressure is insufficient	Study inlet / outlet pressure
Steam leakage or blow-off	Valve closure is obstructed by rust, etc.	Clean (inspect screen as well)
	X-element is worn or damaged	Replace X-element
	Valve seat is worn or damaged	Replace cover (valve seat is pressed in the cover)
	Improper installation	Correct the installation
	Severe vibration of trap	Reinforce trap piping supports
Leakage from other location	Cover is loose or gasket is worn or damaged	Tighten cover or replace gasket