EXT3T Series

EXT3T is an advanced, self-regulating heat trace cable that can be used for efficient and reliable pipe freeze protection. EXT3T is suitable for installation on the outside of both metallic and non-metallic pipes and with approvals for direct earth burial and wet locations can be installed indoors and outdoors.

In comparison to Heat-Line’s very popular EXT5R and Paladin for Pipe systems which have an outer elastomeric heat trace jacket, the EXT3T outer heating cable jacket is manufactured of a progressive fluoropolymer. As a result the EXT3T heat cable does not deteriorate when exposed to aggressive and corrosive, organic or inorganic materials which may be found in buildings such as barns, workshops, garages, and or commercial/industrial factories. EXT3T being a very versatile product can also be installed inside most non-pressurized, non-potable pipes and drains as Heat-Line offers the only external heating cables on the market that are wet location certified by cCSAus. The EXT3T system is easily adapted to a variety of applications including cottages, homes, resorts, farms, and commercial/ industrial buildings.

external heating cable on dispensing reel
on pipe heat cable for special usages


EXT3T is resistive to harmful and aggressive substances given its outer fluoropolymer jacket, making it the product of choice in applications such as garages where soaps, gasoline or oil may come in contact with the heating cable. EXT3T is also a great product in harsh farm applications where the heating cable may come into contact with animal urine and manure.

Heat-Line Paladin & EXT Series External Pipe Freeze Protection

The EXT3T trace heating cable is supplied as a job-ready, pre-assembled system that is a safe and reliable solution for all metallic and non-metallic pipe types and materials of many sizes. This includes but is not limited to copper, PEX, polyethylene, ABS, PVC, galvanized, stainless, ductile iron, rubber, vinyl and more. Even in applications where pipes are intended to be dry for short or extended periods of time, EXT3T will never over-heat or melt the pipe due to its advanced self-regulating heat tracing technology.

EXT3T is supplied job-ready as a plug-in unit with GFCI protection with a 4 ft. (1.2m) power lead and is factory finished to length making installation simple, fast and cost effective. The need for an electrician to provide on-site power and complex terminations is eliminated. Other power supply options are available.

EXT3T is cCSAus certified to meet and or exceed North America standards. EXT3T is the only known heating cable available on the market that carries direct earth burial and wet location approvals making it suitable to install in a variety of applications like never before.

EXT3T employs the unique and advanced performance of self-regulating heat cable technology. Constructed of self-regulating heat cable technology the EXT3T can effectively increase heat and energy output microscopically to points along its length which are cold and simultaneously reduce heat and energy output to points which are warm. You never have to worry about the EXT3T heating cable overheating causing risk of melting and fire because of the self-regulating heat trace cable technology. EXT3T gives you the peace of mind of reliable freeze protection without the risk. It has become an essential product for farmers and barn managers to provide safe and reliable freeze protection in barns and stables.

To further increase the energy efficiency of your EXT3T heating cable system, it is recommended to add thermal insulation and a thermostat. The additional thermal insulation works to reduce heat loss, and the thermostat allows you to duty cycle your EXT3T system based on external pipe temperature. Both accessories combined can increase energy efficiency by as much as 80%.

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EXT3T is an external heat tracing system designed to provide reliable freeze protection of metallic and non-metallic pipes. Examples include but are not limited to:

  • Existing water supply lines subject to freezing
  • Drain pipes consisting of drinking water
  • Small diameter water supply lines
  • Large diameter pipes and hoses
  • All metallic and non-metallic pipes and drains
  • Sewage, septic and effluent pipes
  • Most metallic and non-metallic tanks

As EXT3T is also wet location approved, it may also be used inside non-pressurized, applications. Examples include but are not limited to:

  • Drains and culverts

EXT3T can be found providing freeze protection in many of the following places:

  • Lake homes and cottages
  • Farm, agriculture
  • Commercial, industrial
  • Garage and workshops
  • Food processing plants
  • Construction sites
  • Camps and RV’s
  • Mining and exploration
  • And more

As EXT3T is a high quality product, it is installed in a different fashion as compared to traditional style heat tape products. Other hardware store heat tape/ cable products must be pitched or spiraled around the pipes in order to apply adequate amounts of heat to un-insulated pipes making them very high in energy consumption. With EXT3T, the heating cable is simply applied on to the pipe in a single or dual trace; reducing overall length of product by as much as 60% in single trace applications.

When combined with thermal insulation, the amount of heat required is greatly reduced; thereby generating greater energy savings.

EXT3T can be utilized in many specialized applications. If you feel you have a special or unique application for EXT3T please contact Heat-Line directly and speak with one of our knowledgeable product specialists.

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  • Approved for applications with aggressive fluids or materials
  • Suitable for small and large pipe diameters
  • 5 year limited warranty, 10 year extended warranty available
  • Can be installed on all metallic and non-metallic pipes, tanks and vessels
  • Provides reliable freeze protection of all pipe diameters (when properly measured and installed)
  • Easily and quickly installed on most pipes without their removal
  • Can be fully insulated to increase energy efficiency
  • Control devices including timers and thermostats are optional
  • Available in 10ft. (3m) increments from 10 ft. (40m) to a maximum length of 550 ft. (167m), custom lengths are available
  • Ground fault protection is included with all EXT3T GFC models
  • EXT3T GFC models simply plug into a 120V or 240V receptacle. No extra electrical work is required (Cord set (hard wire) connected EXT3T models available upon request)


  • cCSAus approved (Canada and USA)
  • Manufactured in North America
  • Direct earth burial approved
  • Wet location approved
  • Will never melt or burn through the water pipe, even if the pipe is dry
  • Can be overlapped without the concern of overheating
  • Most reliable and energy efficient system on the market
  • No other product combines the features and offers the flexibility of EXT3T by Heat-Line
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  • cCSAus approved (Canada and USA)
  • Designation Type W
  • Installation Type A USA

Electrical Specifications:

  • Self-regulating/conductive polymer heating cable
  • 120V systems – 3W/ft. (9W/m) at 50°F (10°C) maximum length of 250 ft. (76m)
  • 240V systems – 3W/ft. (9w/m) at 50°F (10°C) maximum length 550 ft. (167m)
  • 120 Volt GFC models - 4 ft. (1.2 m) power supply lead with 27 milliamp ground fault circuit interrupter plug-in device
  • 240 Volt GFC models - 6 ft. (1.8 m) power supply lead with 27 milliamp ground fault circuit interrupter plug-in device
  • CS models - 6 ft. (1.8 m), 12- 14 AWG SJEOOW supply cord for direct hard wire connection, GFCI must be field installed

Plumbing Specifications:

  • Suitable for multiple pipe sizes both metallic and non-metallic
  • Fluropolymer outer heating cable jacket
  • Nominal EXT3T heating cable thickness 0.25 in. (6.4mm) / width 0.425 in.(10.8mm)
  • Direct earth burial and wet location approved
  • Suitable for exposure temperatures up to 150°F (65°C)
  • Manufactured in North America


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Measuring Recommendations for EXT3T

Always measure prior to ordering. Do not assume or estimate the length required as the Heat-Line EXT3T heating cable system cannot be extended.

- The EXT3T is an advanced external self-regulating heating cable system factory finished and supplied job-ready to a pre-determined length provided at time of order.

- While the EXT3T system is designed for external heat tracing of small and larger diameter metallic and non-metallic pipes, it can also be installed within gravity fed ground water drains given its wet location approval.

- EXT3T systems are priced and manufactured in standard lengths of 10 ft. (3m) increments up to 250 ft. (76.2m) in 120 volt, and in 10 ft. (3m) increments from 10 ft. to 550 ft. (3m – 167.6m) in 240 volt.

- Given that EXT3T systems are provided in 10 ft. (3m) increments it is wise to always round up to the nearest standard length. For example, if an 18ft. (5.5m) system was required, Heat-Line recommends to round up to a 20 ft. (6m) system.

- When measuring the length required of an external heating cable system, such as the EXT3T, care is required to ensure that the ordered length is exact or longer than required. There is no way to lengthen the EXT3T product when on site.

- For the best results when calculating the required length of EXT3T that is required you should gather the following information:

  • Pipe/ Drain Type/ Material (PVC, Copper, PEX, ABS, Iron Pipe, Galvanized, etc.)
  • Pipe/ Drain Diameter
  • Pipe/ Drain Length
  • Number of Valves and or Spigots Along The Length of The Pipe
  • Insulation Type and Thickness if applicable (For information and or recommendations on insulation contact a Heat-Line application specialist)
  • Lowest Outdoor Ambient Temperature
  • Is the Pipe or Drain Buried or Above Ground
  • Fluid in Pipe/ Drain

Determining the length of EXT3T heat trace required for common external heat tracing of metallic and non-metallic (plastic) pipes could not be simpler. A single trace of EXT3T is commonly applied at the 4 or 8 O’clock position, while dual tracing is applied at both the 4 and 8 O’clock position. Valves and or spigots are generally wrapped. (For install information refer to EXT3T Manual)

- For lengths of pipe that have spigots and or valves you will need to add at least 2.5 ft. (0.75m) of additional heater per valve and or spigot.

- For special applications and or pipe diameters greater than 2 inches (51mm) contact Heat-Line and speak with an application specialist.

- Determining the length of EXT3T heat trace required for internal heat tracing of metallic and non-metallic drains could not be simpler as the objective is to create a melt water pathway or channel within the larger drain. As a result, a common single (straight) internal length of the EXT3T is all that is commonly required within the drain.

- In application where the outlet of the drain is exposed, Heat-Line recommends to double back or dual trace the last 2-5 ft. (0.6m – 1.5m) of the drain.

- If you are able to external measure the drain, as it is exposed, do so with a flexible measuring device such as a measuring tape. In applications where the existing problematic drain is below grade it is beneficial to internally measure the length of heating cable required with an electrical or plumbers fish tape.

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EXT3T is a custom order product however in most cases it can be shipped out within 3 days from time of order. Please call for current availability and lead times. For a quotation on this product and more CLICK HERE.


Included in a EXT3T system:

  • Factory finished, self-regulating heating cable set in a pre-determined length
  • 120V GFC model: 4 ft. (1.2 m) power supply lead with 27 milliamp ground fault circuit interrupter plug-in device 
  • 240V GFC model: 6 ft. (1.8 m) power supply lead with 27 milliamp ground fault circuit interrupter plug-in device 
  • CS model: 6 ft. (1.8 m), 12- 14 AWG SJEOOW supply cord for direct hard wire connection, GFCI must be field installed
  • 5 year limited warranty
  • Clear, concise installation and support documentation


EXT3T Accessories: 

HLA-120 120V plug-in thermostat (GFC)
120/240V hard wire thermostat with GFCI (CS)
TIMER-120P 120V plug-in timer (GFC)
TIMER-240P 240V plug-in timer (GFC)
120/240V hard wire timer (CS)
MA-10 120/240V GFCI/ELCI (CS)
INSUL-1.00 Insulation sleeve for 1 inch ID pipe (1 5/8 inch ID, 6 ft long)
INSUL-1.25 Insulation sleeve for 1 1/4 inch ID pipe (1 7/8 inch ID, 6 ft long)
INSUL-2.00 Insulation sleeve for 2 inch ID pipe (2 5/8 inch ID, 6 ft long)
INSUL-3.00 Insulation sleeve for 3 inch ID pipe (3 1/2 inch ID, 6 ft long)
INSUL-4.00 Insulation sleeve for 4 inch ID pipe (4 1/2 inch ID, 6 ft long)
HLP-TAPE Tape for insulation sleeves (100 ft)
INSUL-FOIL Aluminum bubble foil insulation (16 in wide, sold by the foot)
INSUL-TAPE All weather Aluminum foil tape (150 ft)
PLD-CG Cable guards/protectors (pkg of 4, 6 in each)
WARRANTY Extended 10 year limited warranty




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Q - What is the difference between EXT3T and EXT5R?

A – The EXT3T heating cable is constructed with a fluoropolymer outer jacket resistance to aggressive fluids and or materials, such as horse urine or manure. In comparisons the EXT5R and Paladin for Pipe heating cables are constructed with an elastomeric outer jacket design for ordinary installations that will not come into contact with aggressive chemicals. Apart from this main application difference the EXT3T is a 3W/ft. (9W/m) at 50°F (10°C) self-regulating heating cable and the EXT5R is a 5W/ft. (15W/m) at 50°F (10C) self-regulating heating cable.


Q - Is EXT3T safe to use on plastic pipes?

A- The EXT3T system is approved for use on all metallic and non-metallic pipe applications. The advance self-regulating technology employed in the EXT3T product renders it safe on plastic pipes even when dry as it can never overheat and damage the pipes.


Q - Can EXT3T be buried?

A – Yes. The EXT3T system (along with Paladin and EXT5R) is certified for both direct burial and wet locations making the heating cable and proprietary end-seal termination completely safe to burry.


Q - Can EXT3T only be used to trace pipes on the outside?

A - No. EXT3T was originally intended to be installed on the outside of the pipes however because of its specialized wet location approval it is suitable to be placed inside non-pressurized pipes such as drains.


Q - Do I have to spiral the EXT3T system around the pipe or just run straight along the side of the pipe?

A - Since EXT3T has extraordinary heat transfer properties it can be simply run straight along the pipe (single or dual trace) without the need to pitch or spiral the heater. This unique ability means that the overall length of heating cable required greatly reduced, decreasing overall operating costs.


Q - Does EXT3T come with a thermostat?

A - A thermostat is not included with the EXT3T product as they are not required for proper and safe operation; however a thermostat can be purchased as an additional accessory. Depending on system applications, or where automatic operation is preferred, a thermostat can be used to switch the system on and off to help conserve power or to duty cycle the system. When combined with insulation thermostats can substantially increase energy efficiency.


Q - Can I (the homeowner) install EXT3T?

A – Heat-Line provides proper and easy to follow installation instructions with all of our products, and offers market leading technical support. As a result, most Heat-Line systems, including EXT3T can be installed by homeowners; however, Heat-Line commonly recommends that a qualified tradesperson complete the installation process.


Q - What do I do if I have extra EXT3T heating cable?

A - If you have extra heater you can loop the excess back up the pipe or concentrate more heating cable in more exposed sections of the pipe. If needed it is safe for the heating cable to overlap as it is self-regulating and will not overheat.


Q - Does the unit shut off when not required?

A – No. EXT3T self-regulating heating cable systems increase heat output with cold but more importantly, decrease heat output with warmth. As a result, Heat-Line brand products are very energy efficient to operate, but do not completely shut off as they can only idle their output to a minimum amount. To completely shut off the system it must be unplugged or installed with a thermostat. Heat-Line brand systems should be unplugged or shut off when not required (summer months) and tested each year before use.


Q - Does a 240-volt system use less power than a 120-volt system?

A – No - Energy efficiency has nothing to do with the designated voltage. We pay for the energy in watts, not in volts. Years ago the term "more efficient" was attached to 240 volt systems because you can put more load or amperage on a 240 volt circuit. Unfortunately the term more efficient somehow became misinterpreted to mean "more energy efficient" which is not the case.


Q - If the power fails do I have to reset the unit?

A - Heat-Line products including EXT3T are designed to turn back on as soon as the power to the unit is supplied. Once re-energized the EXT3T system has the ability to increase its output to immediately begin to defrost any section of the pipe that has or was close to freezing during the power outage. In many instances defrosting the pipe can take as little as an hour or less.


Q - How much power does a EXT3T consume?

A- All Heat-Line brand systems including EXT3T employ Heat-Line’s advanced self-regulating heating cable technology which operates to deliver energy and heat output to areas of the pipe that are cold and reduces energy and heat output to areas which are warm. While the overall amount of energy consumed depends on multiple factors you can be assured that you are installing the most energy efficient heating cable system available. If you would like to reduce your energy consumption further you can investigate the addition of a thermostat, timer, and or other control device.


Q- Is there a maximum length of EXT3T heating cable systems?

A – Yes. The maximum circuit length of EXT3T that is allowed on a 120V circuit is 250ft. (76m), and or 550ft. (167m) on a 240V circuit.


Q – Can EXT3T be cut to length if too long?

A – No. The EXT3T system manufactured by Heat-Line is a pre-assembled factory terminated advanced self-regulating heating cable system that is not designed to be field terminated and or tailored to length. If you have extra heater you can loop the excess back up the pipe or concentrate more heating cable in more exposed sections of the pipe.


Q – My EXT3T system is too short; can I add a small section onto the end? If not, what can be done?

A – No. The EXT3T system manufactured by Heat-Line is a pre-assembled advance self-regulating heating cable system that includes a proprietary end-seal termination and fluoropolymer heating cable jacket engineered to be certified for direct burial and wet locations. As such the EXT3T system cannot be spliced together in the field. If greater length of the EXT3T is required you may purchase a single continuous product of the proper length, and or relocate a second power source and install an additional EXT3T system to complete the required freeze protection.


Q – Can I install the EXT3T system on a pipe that is inside a wall?

A – No. It is not recommended to install the EXT3T heating cable system behind a wall as this renders the product unserviceable and means that it is not easily inspected should the product and or piping need to be examined.


Q- What type of insulation should I use with the EXT3T system?

A – Heat-Line recommends to use insulation that is best suited to the environment in which it is going to be installed. A common type of insulation employed with EXT3T heating cables is fire resistance water proof pipe foam insulation sleeves. You are also able to implement fiberglass insulation provided it is properly weatherproofed based on the environment.


Q – Where do I purchase the EXT3T heating cable system?

A – The EXT3T heating cable system manufactured by Heat-Line is available directly through Heat-Line and or any of our Heat-Line product distributors. For a list of Heat-Line product distributors in Canada and the United States please contact Heat-Line directly on our toll free number at (800) 584-4944.


Q- Will the EXT3T system work with DC voltage?

A – No. The EXT3T heating cable system is designed to work with AC voltage only. For 12 volt or 24 volt DC applications see Kompensator.


Q – What is the indication light on the GFCI located in the electrical lead of the GFC EXT5R models for?

A – The indication light located on the GFCI device included with all GFC model EXT3T systems verifies that power is provided to the GFCI device and that the GFCI is allowing power to pass through to the heating cable device.


Q – Do I have to use insulation with the EXT3T system?

A – Insulation is highly recommended when using the EXT3T system, especially if the installation is above ground in ambient outdoor air. Insulation helps reduce the overall heat loss and therefore reduces the amount of energy the EXT3T heating cable must consume.


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