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Max Pressure: 2.0 MPaGMax Temp: 220 °CBrass Body

TLV NF6 Automatic Non-freeze Valve

TLV NF6 brass automatic non-freeze drain valve for free float steam traps. Features 2.0 MPaG max operating pressure, 220 °C max temperature, and built-in screen.

TLV NF6 Automatic Non-freeze Valve

The TLV NF6 is a compact, brass automatic non-freeze valve designed as a drain option for free float steam traps. It reliably drains residual condensate from traps provided with drain plugs to prevent freeze-up in cold areas. The valve opens automatically to drain residual condensate shortly after the shut-off of steam-using equipment when steam pressure in the trap decreases to approximately 0.2 barg (0.02 MPaG). It closes steam-tight immediately after startup when the pressure rises to about 0.3 barg (0.03 MPaG). The normal operation of the steam trap is unaffected by the NF6, and its built-in screen protects the valve from clogging.

TLV NF6 automatic non-freeze valve product photo

Features

  • Opens to drain residual condensate at approx. 0.2 barg (0.02 MPaG).
  • Closes steam-tight at approx. 0.3 barg (0.03 MPaG).
  • Normal operation of the steam trap is unaffected.
  • Built-in screen protects the valve from clogging.
  • All internal parts are made of stainless steel and brass.

Specifications

ModelNF6
ConnectionScrewed
Size1/4"
Maximum Operating Pressure (PMO)2.0 MPaG (20 barg)
Maximum Operating Temperature (TMO)220 °C
Valve Opening Pressureapprox. 0.02 MPaG (0.2 barg)
Valve Closing Pressureapprox. 0.03 MPaG (0.3 barg)

Pressure Shell Design Conditions (Not Operating Conditions):

  • Maximum Allowable Pressure (PMA): 2.0 MPaG (20 barg)
  • Maximum Allowable Temperature (TMA): 220 °C

WARNING

Install properly and DO NOT use this product outside the recommended operating pressure, temperature and other specification ranges. Improper use may result in such hazards as damage to the product or malfunctions which may lead to serious accidents. Local regulations may restrict the use of this product to below the conditions quoted.

INFO

When used in extreme cold, due to the possibility of freezing while discharging, prevention of freezing cannot be guaranteed.

Configuration and Materials

TLV NF6 configuration and cross-section diagram

No.DescriptionMaterialDIN*ASTM/AISI*
1BodyBrass C36042.0401B16 C36000
2Valve SeatStainless Steel SUS3031.4305AISI303
3Valve DiscStainless Steel SUS3031.4305AISI303
4Valve Disc GuideBrass C36012.0375B16 C36000
5Coil SpringStainless Steel SUS3041.4301AISI304
6ScreenStainless Steel SUS3041.4301AISI304
7Gasket**Copper C1100P-B152
  • Equivalent materials ** Only on NF6 with straight G(PF) thread. NF6 with tapered R(PT) thread has no gasket.

Dimensions

TLV NF6 dimensions drawing

SizeL (mm)H (mm)Weight (kg)
1/4"51240.1

Inlet: G(PF) 1/4 male or R(PT) 1/4, Outlet: G(PF) 1/4 female. Other standards available.

Discharge Capacity

TLV NF6 discharge capacity chart

  1. Differential pressure is the difference between inlet and outlet pressure of the valve.
  2. The chart is applicable to condensate below 100 °C.

Installation

WARNING

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.

WARNING

Do not use excessive force when connecting threaded pipes to the product. Over-tightening may cause breakage leading to fluid discharge, which may cause burns or other injury.

  1. Before installing the non-freeze valve, blow out any piping scraps, dirt and oil from the piping and steam trap the non-freeze valve is to be installed on.
  2. Before installation, be sure to remove any protective seals.
  3. Install the non-freeze valve at the proper location on the steam trap so that the flow direction of the valve matches with that of condensate.
  4. Install outlet piping. Make sure that the internal diameter of the pipe and joints are thick and short with an inner diameter of ø6 mm (15/64") or larger.
  5. Do not install a needle or other valve at the outlet (except for full-bore ball valves).
  6. Open the inlet and outlet valves of the steam trap and allow the trap to operate normally. After that, close the inlet and outlet valves and check to make sure that the non-freeze valve opens and functions properly when the internal pressure (temperature) decreases.

Special Considerations for Product Use

1. Outlet pipe should have as steep a downward incline as possible Condensate needs to be discharged from the piping before the temperature decreases below the freezing point. This product cannot function once freezing has occurred at the outlet side. Do not recover the condensate.

2. Outlet piping should be as thick and as short as possible Freezing occurs from the outside of the outlet pipe. If the outlet pipe is thin and long, the condensate temperature can decrease while flowing, gradually freezing along the pipe's inner surface. Eventually, the pipe may become blocked, with condensate backing up and freezing in the steam trap, possibly causing damage. To prevent such an occurrence, the outlet pipe should be as thick and as short as possible with an internal diameter ø6 mm (15/64") or larger and discharge to atmosphere.

3. Relation between required inlet pressure and length of NF6 outlet pipe If there are any bends, or the pipe length is long, outlet pressure of NF6 increases due to high resistance from the pipe, and the valve may not close. To avoid such a phenomenon, use the non-freeze valve on a steam trap with an inlet pressure shown on the following graph.

TLV NF6 relation between required inlet pressure and length of outlet pipe

Use the non-freeze valve on a steam trap with an inlet pressure as shown on the graph. ø6 mm (15/64") or larger internal diameter and bending at no more than 3 locations.

Maintenance and Troubleshooting

WARNING

When disassembling or removing the product, wait until the internal pressure equals atmospheric pressure and the surface of the product has cooled to room temperature. Disassembling or removing the product when it is hot or under pressure may lead to discharge of fluids, causing burns, other injuries or damage.

Parts Inspection

PartProcedure
Valve Disc & Valve SeatCheck for oil film, warping, scratches or other wear
ScreenCheck for clogging or corrosion

Table of Tightening Torques

PartTorque N·m (lbf·ft)Distance Across Flats mm (in)
Valve Seat*35 (26)17 (21/32)
Body (Straight G(PF) thread)*35 (26)21 (13/16)
Body (Tapered R(PT) thread)30 (22)21 (13/16)

*Coat threads with anti-seize.

Exploded View

TLV NF6 exploded view for maintenance

Troubleshooting

ProblemCauseRemedy
No condensate is discharged (blocked) or discharge is poorValve disc, valve seat, screen, or piping is clogged with rust or scaleClean parts
Freezing occurs on outlet pipe, etc.Examine the size, length and installation of the outlet pipe and take appropriate corrective measures
Steam is discharged or leaks from the outlet (blowing) (steam leakage)Rust or scale or other build up have accumulated on the valve disc or valve seatClean parts
Valve disc or valve seat are damagedReplace with a new valve and valve seat
Improper installation orientationReinstall with correct flow direction
Improper installation, size or length of outlet pipeMake sure outlet pipe is at least ø6 mm (15/64") internal dia., of appropriate length and has no more than 3 bends
Steam leaks from a place other than the outletGasket deterioration or damageReplace with a new gasket
Improper tightening torques were usedTighten to the proper torque