Heat Tape versus Heating Cable:

What's the difference, and which one do I need?

(Part of our collection of articles on Everything You Need to Know about Heating Cable)

We talk to folks all the time who ask us for "heat tape" when what they're really looking for is heat trace cable – which is also known as heating cable, heat tracing cable, or heater cable. The confusion is understandable: lots of hardware stores sell roof de-icing kits that include heating cable, but call it "heat tape." (If that's what you're looking for, you've come to the right place; you can find those roof heating cable kits here.) But despite the similarity in names, there is a difference! There are a few industrial and scientific applications where you could use either one, but most applications clearly call for one or the other. This page will discuss the differences between heat tape and heating cable, as well as some of the applications where one or the other should be used, and you'll find links to the pages where you can purchase our heat tapes and heat trace cables. We also have some information on a similar, lesser-known but very useful, product, heating cords.

Of course, if you have any questions about the products or your application, please feel free to give us a call at (866) 685-4443, send us an e-mail at info@oemheaters.com, or fill out a contact form, and we'll be glad to help you out.

Quick comparison

Heating Tape, Heating Cable, Heating Cords: At a Glance

Heating cable	Heating tape	Heating cord
Lower power densities and temperatures, with maximum temperatures ranging from 150°F to 500°F, and including low-intensity cables well suited for freeze prevention.	Higher power densities and temperatures, ranging from tapes with a maximum of 305° up to very-high-temperature tapes rated for up to 1400°F (760°C).	Power densities and construction comparable to those of heating tape.
Available with housing styles that are resistant to water and many chemicals, and suitable for outdoor use.	Some styles are resistant to moisture or suitable for use on electrically conductive surfaces, but they must not be submerged, and are generally intended for indoor applications.
Fairly stiff (about as flexible as a garden hose), but very good for spiraling around pipes.	Highly flexible to conform to tight contours and odd shapes.	As flexible as heating tape, but more forgiving of imprecise wrapping.
Somewhat rounded, resembling type NM or Romex™ cable. Power density measured in watts per foot.	Flat in cross-section. Power density measured in watts per square inch.	Round in cross-section.
Many styles can be cut to length, and terminations added, in the field.	Sold in fixed lengths from 2 to 20 feet (depending on the style).	Built to order or sold in fixed lengths from 3 to 24 feet.

Heating cable

Heating cable looks more like standard two-conductor house wiring cable (Type NM or Romex™) and is not nearly as flexible as heat tape – most varieties are about as flexible as a garden hose. The stiffness is related to one of the main differences between them and heat tapes: heating cables are enclosed in a housing that protects the heating elements and means you can use the heater in a broader range of environments. Heating cable can also be cut to length and terminated with electrical connections, and in fact we sell it by the foot. There are two main types of heating cable:

Self-regulating or self-limiting heating cable is made so that it will not rise above a certain temperature. (This doesn't mean that it will stay at the right temperature without a temperature control, only that it won't overheat and burn out. The name misleads many people—so we've written an article about what "self-regulating" really means. We recommend at least a basic thermostat.) They are on the low end of the temperature range, with styles suitable for applications up to 250°F. They are available in 120 V and 240 V versions; the latter can also run at 208, 220, or 277 V. Self-regulating cables come in two varieties:

• Standard-temperature self-regulating cable ranges up to 150°F. It's available with nominal heat outputs of 3 W/ft, 5 W/ft, 8 W/ft, and 10 W/ft.
• Mid-temperature self-regulating cable ranges up to 250°F. It's available with nominal heat outputs of 5 W/ft, 10 W/ft, and 15 W/ft.

Constant-wattage heating cable, by contrast, doesn't control its own temperature, so it requires a controller. It is available for higher temperatures, with styles ranging up to 500°F. It can be run on a wider range of voltages: 120, 208, 240, 277, and 480 V. It comes in several varieties, each of which has different advantages. To simplify the choice, you can use this chart:

Heat tape

Heat tape is the product to use for applications where small, cylindrical sections need high power densities (which usually indicates high temperatures as well). Most heat tape is available on 120 V and 240 V versions, with power ranging from 52 W to 3,135 W. The power density, which we measure in W/in², ranges from 4.3 W/in² up to 13.1 W/in² for the high-temperature versions. Heat tape is a constant-wattage product, as opposed to self-regulating products that have built-in protection against overheating, and for this reason you must use a temperature controller of some type with it.

As far as dimensions go, one of the biggest differences between heat tape and heating cable is that heat tape is sold in fixed lengths – ours range from 2 to 20 feet in length, depending on the style. With the exception of cut-to-length heat tape (which is not available for online sale, though you can contact us to find out more), you cannot trim heat tape to length.

We carry several different varieties of heat tape for a wide range of applications:

• Silicone rubber heat tapes are a good heat tape for applications up to 450°F, and are chemical- and moisture-resistant. (Note that does not mean that they are chemical- and moisture-proof; they cannot be immersed!) They're also available
  • with a built-in adjustable thermostat and
  • in a grounded version for applications in ordinary locations up to 305°F.
• Fiberglass-insulated heat tapes come without controls – no built-in thermostat. They are available in several different configurations:
  • A grounded version that is suitable for applications to 482°F.
  • A version suitable for use on electrically non-conductive surfaces, and
  • one for use on conductive surfaces – both of which can be used for application temperatures up to 900°F.
• Heat tapes made of Samox™, a high-temperature woven fabric, are available for applications to 1400°F, and come in two varieties:
  • A version for use on electrically non-conductive surfaces and
  • A version for use on conductive surfaces.

Heating cords

Heating cords are much like heating tapes, but are rounded in cross-section. This decreases the exposure surface and makes heat conduction somewhat less efficient, but the advantage is a heater that is much more forgiving of being wrapped imprecisely. Heating tapes must be wrapped very carefully to ensure that the full flat width of the tape is in constant contact with the surface being heated. If heating tape is switched on while a section of it is exposed to air on both sides – whether because it's bridging a corner or because it's been kinked during wrapping – that section won't be able to transfer its heat to the other object, and all that heat will build up in the tape and overheat it. Heating cord, being circular, can't get kinked and doesn't have flat sides. (However, you do still need to make sure that no sections of the cable are exposed in the air without contact to the heated object, or it will still be likely to overheat.)

We can create built-to-order heating cords (just contact us for a quote), and we have stock heating cords, which are available in two styles:

• Standard-temperature heating cords, for temperatures up to 900°F, with a 120 V supply from 64 to 260 W.
• High-temperature heating cords, for temperatures up to 1400°F, with a 120 or 240 V supply from 266 to 1500 W.

So, which one is right for my application?

If, after reading this, you're still not sure which kind of heater is best for your application – or if you just want to talk to an application engineer to make sure you're getting the right kind – you can always get in touch with us: call us up at (866) 685-4443, fill out one of our contact forms, or just email us at info@oemheaters.com. We'll be happy to help.