What they are: Non-metallic Laboratory Faucets engineered to deliver the durability and strength of metal—without the contamination and corrosion metal can introduce—ideal for DI/RO and compatible chemicals in commercial labs.

Materials (wetted path; with Virgin PTFE seals): PVC · Natural Polypropylene (PPN) · HP PVDF

Why DURALINE:
  • Heavy-duty construction: Built to withstand constant use—and occasional misuse—in commercial applications.
  • Injection-molded stanchion: Rigid, impact-resistant body (not an extruded tube) for long service life.
  • Control valve: Positive shutoff with repeatable actuation and 120° of metering control; designed for high cycle life.
  • All-PTFE sealing: Virgin PTFE throughout; encapsulated PTFE shutoff seal kept in compression for reliable, constant on/off operation.
  • Clean media path: Non-metallic wetted components; no elastomers or lubricants used in construction to reduce contamination risk.
  • Updated styling + rugged build: Modern appearance with industrial-grade robustness.
  • Reliability: 5-year warranty against material and manufacturing defects.

Applications:
  • Point-of-use DI/RO water dispensing at benches and sinks.
  • Analytical labs, QA/QC stations, and life-science workflows.
  • Semiconductor support areas and clean manufacturing utilities.
  • General chemical dispensing within material compatibility limits.

Series LG Lab Faucets: Reliable Performance for High-Purity Water Applications

The Series LG Lab Faucets, available in PVC, Natural Polypro, and High Purity PVDF materials, are designed to deliver reliable performance in demanding laboratory environments. These faucets are suitable for a wide range of applications, including distilled, deionized, pharma grade, RO, ultra-filtered water, chemical dispensing, and reagent-grade laboratory water (Type I, Type II, Type III, and USP Type Water).

Key features of the Series LG Lab Faucets include:

• Maximum flow rate of 2.5 GPM @ 80 PSI, fully open
• Removable serrated barb tip for attaching accessories, leaving a 1/4" Female NPT outlet
• "Duraline" zero dead leg control valve for easy open/close operation and 120-degree full flow to closed
• No elastomers, metals, or lubricants used in construction, ensuring compatibility with high-purity water
• Components designed for high traffic, heavy use environments
• Compliance with FDA, USDA, and USP standards
• Ultra-smooth internal flow path and heavy wall construction for durability
• PTFE sealed, encapsulated PTFE shut off seal for extended life
• Black handle with white marker and black "DI" text per SEFA code recommended practice No. 7 for DI Water Applications
• Renewable Duraline control valve by replacing the internal cartridge, DL-RC180-PVD, per SEFA 7-2010-8.2a
• Positive stop at off position
• 3/8" Female NPT inlet supply connection, with included 3/8" O.D. tube x 3/8" MNPT compression tube fitting

Choose the Series LG Lab Faucets for your laboratory and experience the benefits of a high-quality, reliable water dispensing solution. Click on the item numbers below to view additional specifications and downloads, including data sheets and parts lists

The Marquest Lab Faucet with Water Quality Light is specifically engineered for handling distilled, deionized, reverse osmosis, and ultra-filtered water types, suitable for Type I, II, and III water. This faucet can safely operate at pressures up to 150 PSI. It features a Water Quality Light designed to monitor water purity across specific resistivity thresholds, including 10K, 50K, 200K, 500K, and 1 Meg ohm/cm². The light displays green when water purity is above these thresholds and switches to red to indicate when purity falls below them.

Powered by a wall transformer that converts 120 VAC to 9VDC, this faucet is designed for safety and durability, complemented by a 9-foot cord. It supports a maximum flow rate of 2.5 GPM at 80 PSI and includes a removable serrated barb tip to easily attach various accessories. Constructed to withstand rigorous use, this faucet complies with the material and safety standards set by the FDA, USDA, and USP. It features a 3/8" Fem NPT inlet and a 3/8" O.D. tube x 3/8" MNPT compression fitting, ensuring a reliable and precise water control solution for engineers, technical users, and distributor salespeople.

Series LG Lab Faucets: PVC, Natural Polypro, and High Purity PVDF

Distilled, Deionized, RO, and Ultra Filtrated Water Applications

• Max flow of 2.5 GPM @ 80 PSI, Full Open
• Removable Serrated Barb Tip (Leaves 1/4" Fem NPT Outlet), attach accessory of your choice
• "Duraline" zero dead leg control valve offers easy open/close operation, 120 deg full flow to closed
• No elastomers, metals, or lubricants used in construction
• All components designed for high traffic, hard use environments
• FDA, USDA, and USP standards are either met and/or exceeded
• Ultra smooth internal flow path
• Unique heavy wall construction
• PTFE sealed, encapsulated PTFE shut off seal for unlimited life
• Black handle with white marker and black "DI" text per SEFA code recommended practice No. 7 for DI Water Applications
• Duraline control valve is completely renewable by replacing the internal cartridge, per SEFA 7-2010-8.2a
• Positive stop at off position
• 3/8" Fem NPT inlet supply connection, 3/8" O.D. tube x 3/8" MNPT compression tube fitting inlcluded

PLEASE CLICK AN ITEM # BELOW TO VIEW ADDITIONAL SPECIFICATIONS & DOWNLOADS

Series LG Lab Faucets w/ 1/4 Turn Lab Ball Valve: PVC
Fields of Application: Potable Water, Type III Water, & Chemical Dispensing.

• Working Pressure: Maximum 150 psi at 70 Degrees Farenheit 
• Geon HR-5509 PVC Material. Listed under NSF Standard 14/61 for both potable water and DWV applications and FDA approved
• FDA, USDA, and USP standards are either met and/or exceeded.
• Beautifully finished to enhance all installations
• All injection molded, rugged design and construction
• Standard 3/8" female NPT inlet connection
• Outlet barb fitting connects to different size tubing
• Lab Valve offers quick 1/4 turn on/off control

PLEASE CLICK ITEM # BELOW TO VIEW ADDITIONAL SPECIFICATIONS & DOWNLOADS

Series LG Lab Faucets w/ 1/4 Turn Lab Ball Valve: PVC
Fields of Application: Potable Water, Type III Water, & Chemical Dispensing.

• Working Pressure: Maximum 150 psi at 70 Degrees Farenheit 
• Geon HR-5509 PVC Material. Listed under NSF Standard 14/61 for both potable water and DWV applications and FDA approved
• FDA, USDA, and USP standards are either met and/or exceeded.
• Beautifully finished to enhance all installations
• All injection molded, rugged design and construction
• Standard 3/8" female NPT inlet connection
• Outlet barb fitting connects to different size tubing
• Lab Valve offers quick 1/4 turn on/off control
  

  PLEASE CLICK ITEM # BELOW TO VIEW ADDITIONAL SPECIFICATIONS & DOWNLOADS

Series LG Lab Faucets: PVC, Natural Polypro, and High Purity PVDF

Fields of Application: Distilled, Deionized, RO, Ultra Filtrated Water, Chemical Dispensing.

• Working Pressure: Maximum 150 psi at 70 Degrees Farenheit
• Materials: PVC, Unpigmented Natural Polypropylene, Hi-Purity Natural PVDF
• Materials listed under NSF Standard 14/61 for both potable water and DWV applications and FDA approved FDA, USDA, and USP standards are either met and/or exceeded.
• Beautifully finished to enhance all installations
• All injection molded, rugged design and construction
• Standard 3/8" female NPT inlet connection, other connections available
• Outlet barb fitting connects to different size tubing
• Union Ball Valve provides adjustable orientation of handle and gooseneck, higher flow rates and 1/4 turn on/off.

PLEASE CLICK ITEM # BELOW TO VIEW ADDITIONAL SPECIFICATIONS & DOWNLOADS

Series LG Lab Faucets: PVC, Natural Polypro, and High Purity PVDF

Fields of Application: Distilled, Deionized, RO, Ultra Filtrated Water, Chemical Dispensing.

• Working Pressure: Maximum 150 psi at 70 Degrees Farenheit
• PVC Material listed under NSF Standard 14/61 for both potable water and DWV applications and FDA approved FDA, USDA, and USP standards are either met and/or exceeded.
• Beautifully finished to enhance all installations
• All injection molded, rugged design and construction
• Standard 3/8" female NPT inlet connection
• Outlet barb fitting connects to different size tubing
• Union Ball Valve offers adjustable orientation of valve handle and gooseneck, higher flow rates, and 1/4 turn on/off

Series LG Hot/Cold Laboratory Faucets

Available in PVC, Natural Polypropylene, and High-Purity PVDF

The Series LG Hot/Cold Laboratory Faucets deliver exceptional fluid control in demanding laboratory environments. Engineered specifically for applications requiring ultra-pure water, these faucets feature material options tailored to your specific purity requirements and chemical compatibility needs. Available in both wall-mount and deck-mount configurations to accommodate different laboratory layouts.

Material Options:

• PVC (LG-WD-HC1/LG-DD-HC1): Excellent chemical resistance for general laboratory applications, temperature range 14°F to 140°F (10°C to 60°C)
• Natural Polypropylene (LG-WD-HC2/LG-DD-HC2): Enhanced chemical resistance with reduced extractables, temperature range 46°F to 176°F (8°C to 80°C)
• High-Purity PVDF (LG-WD-HC3/LG-DD-HC3): Superior purity with minimal extractables and phosphate absorption, ideal for DI/ultrapure water systems, extended temperature range -22°F to 248°F (-30°C to 120°C)

Mounting Options:

• Wall Mount (LG-WD-HC Series): Space-saving design ideal for installation against laboratory walls
• Deck Mount (LG-DD-HC Series): Versatile countertop installation for laboratory sinks and workstations

Key Features:

• Advanced Fluid Control: Maximum flow of 2.5 GPM @ 80 PSI with precision temperature adjustment
• Innovative "Duraline" Valves: Zero dead leg hot/cold control valves with 120° operation from full flow to closed
• Contamination-Free Design: No elastomers, metals, or lubricants used in construction
• Laboratory-Grade Construction: Heavy-wall components designed for high-traffic, hard-use environments
• Regulatory Compliance: Meets or exceeds FDA, USDA, and USP standards
• Ultra-Smooth Flow Path: Minimizes turbulence and potential for contamination
• High-Performance Sealing: PTFE sealed, encapsulated PTFE shut-off seal for long-term reliability
• Color-Coded Controls: Black handles with red (hot) and blue (cold) markers and white "HW" and "CW" text per plumbing code
• Renewable Design: Control valves completely renewable by replacing internal cartridge (DL-RC-PVD), compliant with SEFA 7-2010-8.2a
• Positive Stop: Safety feature prevents over-tightening at off position
• Standard Connections: 3/8" Female NPT hot and cold inlet supply connections with 3/8" O.D. tube compression x male fittings included

Applications:

• Potable, Distilled, and Deionized Water Systems
• Reverse Osmosis and Ultra-Filtered Water (Type I, II, III)
• Chemical Dispensing
• Pharmaceutical Research and Production
• Semiconductor Manufacturing
• Medical and Analytical Laboratories
• Research and University Laboratory Facilities

PLEASE CLICK ITEM # BELOW TO VIEW ADDITIONAL SPECIFICATIONS & DOWNLOADS

Series LG Recirculating Lab Faucets: Natural Polypropylene and High Purity PVDF
Fields of Application: Type I, II Deionized, RO, Ultra Filtrated Water.

Marquest Scientific has been manufacturing faucets for the transportation and dispensing of high purity liquids for over 25 years. Recirculation is a feature developed to eliminate any bacterial growth or other biological impurities due to stagnation. This is accomplished by providing a method to allow continuous motion of the liquid during all phases of operation.

• Max flow of 2.5 GPM @ 80 PSI
• Selection of Virgin Natural Polypro or PVDF wetted fluid paths with PTFE Seals
• No elastomers, metals, or lubricants used in construction
• Zero dead leg control valve activation at point of use
• Simplified installation of recirculation module
• All components designed for extreme industrial environments
• FDA, USDA, and USP standards are either met and/or exceeded
• Ultra smooth internal flow path
• Unique heavy wall construction
• Duraline control valve offers easy open / close valve, 120 deg rotation full flow to closed
• PTFE sealed, encapsulated PTFE shut off seal for unlimited life
• Black handle with white marker and black "DI" text per SEFA code recommended practice No. 7 for DI Water Applications
• Duraline control valve is completely renewable by replacing the internal cartridge, per SEFA 7-2010-8.2a
• Positive stop at off position
• Exceptional low torque on/off operation

PLEASE CLICK ITEM # TO VIEW ADDITIONAL SPECIFICATIONS & DOWNLOADS

Download Data Sheet         System Design Notes

**For custom configurations please contact us via email sales@marquestscientific.com 

Series LG Lab Faucets with Atmospheric Vacuum Breaker: PVC, Natural Polypro, and High Purity PVDF

The Series LG Lab Faucets with Atmospheric Vacuum Breaker are designed for use with high purity lab water systems dispensing Type 2 and 3 deionized water, as well as distilled, pharma grade, RO, and ultra-filtered water. These faucets are available in PVC, Natural Polypro, and High Purity PVDF materials to suit various laboratory applications and requirements.

The integrated atmospheric vacuum breaker prevents back-siphonage within the lab water system, ensuring the purity of the dispensed water. The faucets are designed to provide reliable, long-lasting performance in laboratory environments where high purity water is required.

Key features:

• Maximum flow rate of 2.5 GPM @ 80 PSI, fully open
• Removable serrated barb tip (leaves 1/4" Female NPT outlet) for attaching accessories
• "Duraline" zero dead leg control valve with easy open/close operation, 120-degree full flow to closed
• No lubricants or wetted metals used in construction
• Components designed for high traffic, heavy use environments
• Meets and/or exceeds FDA, USDA, and USP standards
• Ultra-smooth internal flow path and heavy wall construction
• PTFE sealed control valve with encapsulated PTFE shut off seal for extended life
• Black handle with white marker and black "DI" text per SEFA code recommended practice No. 7 for DI Water Applications
• Renewable Duraline control valve by replacing the internal cartridge, DL-RC180-PVD,  per SEFA 7-2010-8.2a
• Positive stop at off position
• 3/8" Female NPT inlet supply connection, with included 3/8" O.D. tube x 3/8" MNPT compression tube fitting

The Series LG Lab Faucets with Atmospheric Vacuum Breaker are suitable for a wide range of laboratory water applications, including chemical dispensing and reagent-grade water. With their durable construction and high-quality components, these faucets are an excellent choice for laboratories seeking reliable, high-performance water dispensing solutions.

DURALINE™ Recirculating Laboratory Faucets — Natural Polypropylene (PPN) or PVDF
How it works (core): For return-to-tank DI/UPW loops using a non-pressurized reservoir. A factory-installed compact recirculating module sits below the deck at the inlet of the thru-deck nipple shank. Module ports are 3/8" FNPT inlet from the supply loop and 3/8" FNPT outlet back to the tank. A 0.125" ID recirculating tube seats inside the module, exits the outlet, and returns water to the reservoir to keep the loop moving when the dispense valve is closed.

Materials & purity (wetted path): Natural PP or PVDF; Virgin PTFE seals; no elastomers or lubricants used in construction; non-metallic path; zero-dead-leg at dispense.

Ports & tube interface: Module 3/8" FNPT inlet and 3/8" FNPT outlet; accepts 0.125" ID recirculating tube that returns to the non-pressurized tank.

Key specs: Target velocity ≥ 4.5 ft/s (with 0.125" ID tube, about 0.2 GPM ≈ 5.2 ft/s); pressure rating 120 PSI.

Valve & control: DURALINE control valve with positive shutoff and 120° metering; encapsulated PTFE shutoff seal kept in compression for constant on/off duty; PTFE stem seal; renewable cartridge enables in-place service.

Models: DL-DDR-2 (Natural PP) · DL-DDR-3 (Natural PVDF).

Applications:
  • DI/UPW benches requiring continuous return-to-tank circulation between dispenses
  • High-purity labs mitigating stagnation and biofilm risk at the point of use
  • Multi-faucet series loops with a common return to a non-pressurized reservoir

Series piping note: For faucets in series, use a common return and introduce a small downstream ΔP (diverter tee, valve, or orifice plate) at each faucet to ensure positive recirculation while maintaining dispense pressure.

Installation notes: Use like materials across components; follow best-practice joining for PP or PVDF; verify velocity at the recirculating tube and set the required ΔP when piping in series.

Next step: Select an Item # below for full specifications, installation details, and downloads.

Replacement Goosenecks for Marquest PVC Lab Faucets

Our Replacement Goosenecks are identical to those originally equipped on Marquest PVC Lab Faucets, ensuring a seamless transition when a replacement is necessary due to wear or impact damage. These components are direct matches to your existing setup, allowing for quick and efficient restoration of your faucet's performance.

Select the exact replacement from our range to immediately address any operational disruptions, ensuring your laboratory activities proceed with consistent efficiency. These goosenecks are provided to support the longevity and reliability of your Marquest PVC Lab Faucets, facilitating uninterrupted lab work.