ColdHeat was an American company founded to develop and market products using the proprietary graphite-like compound Athalite. The composite material is claimed by the manufacturer to have the unusual ability to conduct large amounts of heat and return to room temperature in a short amount of time.

The first two products were soldering irons powered by alkaline batteries. The manufacturer claims this soldering iron is unique in that its Athalite tip undergoes a temperature change from ambient temperature to approximately 800 °F (427 °C) and back to ambient within three seconds when the tip is removed from the work.

The tip of this apparatus is split into two sections that completes an electrical circuit when a low electrical resistance is placed across the tip; e.g. metallic contacts, or solder. With a current flowing, the resistance of both the solder and the tip produces enough heat to increase the temperature beyond the melting point of solder. For the light-duty work it was designed for, the Athalite tip heats just enough and can cool very rapidly; however, if applied to something with large thermal capacity such as a metal chassis, the tip can become extremely hot and can take over a minute to cool in an extreme case.

It is thought that the irons cannot be used indiscriminately for all work; the voltage across and current through the tip can damage electronic circuits being soldered. When not in contact with a joint, the split tip has 6 or more volts across it, enough to destroy semiconductor p-n junctions on contact if the iron accidentally touches multiple closely spaced pads. This is not static-electricity damage; any voltage over about 0.7V capable of delivering high current can destroy a semiconductor junction.

According to ColdHeat:

It’s a common misunderstanding that high current in the joint causes the heat. The heat is generated by resistance within the tip. Heat is then conducted to the joint just as in traditional solder tools. Also, current in the joint is limited to the small region between the two tip halves and doesn’t pass through the part being soldered. There is a tiny transient voltage when the tool is applied or removed, but it is orders of magnitude below the levels that cause static-electricity [sic] damage.

The tip is reported to be very easily damaged mechanically. The unit does not have enough power for effective desoldering of many board- and chassis-mounted components. The design of the tip is incompatible with some soldering techniques such as dragging or continuous-flow soldering (a popular technique for hand-soldering high-pin-count SMT packages, based on the principles of wave soldering).

One thorough review of the ColdHeat soldering iron noted:

Athalite is a highly malleable, yet fragile, composite material. The name is derived from “Accelerated THermal Action”. It is most likely composed of graphite. It might also be formed by other materials containing semiconductive elements such as germanium or silicon, as stated in the patent application. A nickel-chromium or other resistive alloy is another possibility listed in the application, but is unlikely to have been used.

Prior to the website’s closure, ColdHeat featured products other than the soldering tool that use the same technology, including a cordless hot-melt glue gun called Freestyle. It heats up much more quickly than others (but not instantly like the solder tool.) It comes with a built-in stand, a pack of mini glue sticks, rechargeable battery, battery charger with its AC adapter, and an instructional manual and a book with different project ideas. However, much like the soldering tool, the Freestyle also had quality issues, usually related to the battery charge, and the heating element. There is a model that runs on AA batteries, for those who prefer their convenience.

ColdHeat had recently released a cordless heated seat, as well as a selection of heated pet beds.

ColdHeat signed a licensing deal with Weller/Cooper Tools in November 2005. Weller sold the ColdHeat Pro as the Weller CHT100.