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Screw Plug Immersion Heaters Frequently asked questions...

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Frequenly Asked Questions on Screw Plug Heaters:

Screw Plug Heater applications include:

  • Water:  Clean, Potable, Deionized, Process, Demineralized

  • Oil:  Asphalt, Fuels, Cooking, Heat Transfer, Crude, Hydraulic

  • Lubricating oils at API specified watt densities

  • Mild Acids

  • Freeze Protection

  • Industrial Water Rinse Tanks

  • Vapor Degreasers

  • Degreasing Solutions 

  • Air & Gas Flow

  • Caustic Solutions

  • Chemical Baths

  • Anti-freeze (glycol) Solutions

  • Paraffin or Wax

  • Electroplating

  • …and more

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A SCREW PLUG HEATERS is an assemble with tubular elements brazed or welded into a NPT.  Screw Plug Heaters are availble with immersed lengths up to 130 inches.  They may be designed from 0.25 KW to 100 KW for mounting via 1”, 1 ¼”, 1 ½”, 2”, 2 ½”, 3” and 4” NPT screw plugs for up to 300 PSIG pressure rating.

They are generally used to heat a known volume of fluid to desired operating temperature.  Sheath materials include Copper, Steel, Stainless 321, Stainless 316L and Incoloy 840.  Sheath selection is determined by the user’s knowledge of the chemical composition of the medium being heated, corrosiveness, contaminants, and controls.

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How do you size SCREW PLUG HEATERS?

SCREW PLUG HEATERS are sized by using the following information:

  • Ambient temperature (worst case).

  • Final temperature desired.

  • Time requirement to heat up (if applicable)

  • Medium being heated, all specifications including corrosiveness, heat density.

  • Watt Density Allowed.               

  • Sheath Material required.

  • Screw Plug Material required.

  • Environmental Operating Conditions for Terminal Enclosure determination.

  • Maximum length and/or size

  • Available operating Voltage & Phase

  • Desired temperature controls (available with or without thermostat, thermocouple, or over-temperature cut out devices)  

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SCREW PLUG HEATERS are used by the following industries:

  • Parts Cleaning Industry

  • Bottle Washing Industry                   

  • Paving

  • Construction Equipment

  • Degreasing

  • Chemical

  • Electroplating

  • Candle Making

  • Food

  • Pet Food

  • And more…

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How long is delivery for SCREW PLUG HEATERS? 

SCREW PLUG HEATERS can usually be shipped in one to two weeks if parts are in stock.  If parts are not in stock, it can take up to six weeks to ship.

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How are SCREW PLUG HEATERS Installed? 

SCREW PLUG HEATERS are installed horizontally near the bottom of the tank/reservoir. The heated portions of the heater elements must remain completely immersed and completely flooded whenever energized.  The cold section of the heater should be extended completely into the fluid being heated.  The heater may overheat, damage and elements, tank or fluid being heater and/or create a possible safety hazard due to high sheath temperature. (See INSTALLATION, OPERATION AND MAINTENANCE INSTRUCTIONS)

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What is the Quality Policy and Warranty on SCREW PLUG HEATERS? 

Warren Electric Corporation SCREW PLUG HEATERS must pass vigorous inspections prior to shipment.  Each individual heating element is checked for electrical leakage and breakdown at high voltage before assembly.  All heaters are 100% hydrostatically pressure tested to insure braze or wells attaching the element to the flange is free of all leaks.  We also electrically test 100% of heaters to ensure they meet the wattage/voltage specifications of the order.  100% of our heaters are also subject to testing for moisture content and hipot testing.  Every heater that Warren Electric Corporation has ever manufactured is identified with a serial number prior to shipment.  These serial numbers are kept on file indefinitely and can be used to identify back to the original inspection sheet and purchase order.   Warranty is 15 months from the date of shipment provided heater failure is not caused by operator error.

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Are there any special certifications available for SCREW PLUG HEATERS? 

SCREW PLUG HEATERS have third party certifications and inspections available for including UL and ISO.   ASME “U” and “UM” Certifications are available for heater casings.

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How do you clean SCREW PLUG HEATERS? 

Instructions to clean SCREW PLUG HEATERS will vary depending on the fluid being heated.  Lime scale is the primary problem for water applications.  If the heater is being used to heat clean water, you may notice a lime scale build up on the elements which can be removed by soaking the heater elements only in CLR (using as directed) and gently using a wire brush to remove heavier deposits if necessary.  Coking is the primary problem for oil applications.  If you are heating oil and notice a build up of oil (called coking) burned onto the elements, the heater elements only can be soaked in kerosene to break down the coke and a wire brush can be used to remove the excess build up if necessary. 

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Our Applications Engineers and Technical Sales people are available to assist you. Please call our toll free "Heat Source" Hotline 1-877-399-HEAT (4328) or contact us.

Download the Warren Electric "Quick Quote" or request a quote online for assistance on your electric heater application!

We are dedicated to meeting and exceeding the needs and expectations of our customers for INNOVATIVE and RELIABLE heating solutions.

Whether it be STANDARD or CUSTOM, a REPLACEMENT or NEW DESIGN... please turn to us for COMPETITIVE PRICING and QUICK DELIVERY on your next Electric Heater application.

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How to Order, PLEASE:
Phone icon Call the "HEAT SOURCE" Hot Line 1-877-399-HEAT (4328) Toll Free
Fax icon Fax Us 1-401-245-9331
Email icon Email Us wec@warrenelectriccorp.com
Download Icon Download a WEC "Quick Quote"
Online Icon Online Fill out a "Quick Quote" Online

Our Design Selector is also available online to assist you.