Keeping warm from the cigarette lighter socket

Even the manufacturers themselves call them different things: mats, pads, covers... But their purpose is one and the same — to warm the rear parts of our anatomy in cold weather. The seat is icy, the "stove" has not "got up to steam" yet — it is precisely for such occasions that the heaters we are about to discuss are needed.

Let us say at the outset: we are looking only at the simplest domestic heaters of the "lay it down and plug it in" kind — they are all powered from the cigarette lighter socket. Built-in heating is admittedly far more convenient and elegant: hidden wiring, buttons and all that, but that is a somewhat different level, with different prices.

The main plus of the cover-pads under review is Spartan simplicity. As for the drawbacks, they have long been known. An aesthete will say that such products clash with the interior. An electrician will remind you that trying to heat even the two front seats means having to buy a splitter of unknown quality — you cannot plug two plugs into one socket. Besides, the stock fuse may take offense... On the "classic" Zhigulis its rating is 8 A, whereas a pair of mats will easily "suck out" a full 10, and more still when cold. The fire safety officer will side with the electrician, adding that "when leaving — put out the light," that is, switch off your heater, or heaven knows what might happen. And the battery will run down anyway if the cigarette lighter socket on your car is live all the time.

Those whom this does not deter and who are set on buying such a heater face a tour of markets and stores — to touch, sniff, compare prices and so on. That is not hard — no advisers are needed here. But one thing you definitely cannot do when buying is peer into the heater's innards — yet is it not scary to sit on it with a valuable part of your body? And what do the little boxes with buttons and LEDs, found on the power cord of some mats, conceal? So we decided — buy, dissect, and show everyone!

Before inviting readers to the photo exhibition "A Heater, Inside and Out," let us suggest delving into the substance of a short test borrowed from NAMI-FOND, the certification body for automotive products.

"Electrically heated covers for car seats are not covered by mandatory certification under the Rules for conducting work within the certification system for mechanical vehicles and trailers, since they are not included in the List of spare parts and accessories for mechanical vehicles and trailers subject to mandatory certification"

All clear? What is curious, though — do the fire safety officers know about this?..

A few words about what you are about to see inside.

Usually, conductors with high electrical resistance and high heat resistance are used as heating elements — recall grandma's iron with a nichrome spiral inside. An ordinary conductor, on the other hand, has far lower resistance and is supposed to simply carry current. If it nevertheless heats up — switch everything off at once and look for a short circuit in the line. The developers, however, sometimes decide things their own way. Slight heating will not harm the wire, and its low resistivity can be offset by "brute-force methods": the conductor laid inside the mat is "well, really long". And nothing happens — it works...

1. Manufacturer / Sensor research and production firm
Product / "Komfort" seat heating mat

No complaints about the "clothing." Springy little straps, a mat surface pleasant to the touch — all is well. But the three-position operating mode switch looks better from the outside than from the inside: a decent printed circuit board has been through the hands of a poor assembler. The green LED did not work from the very start — it was never properly soldered. The heating element — ordinary wiring wire...

Manufacturer / Niko-AVTO, Ulyanovsk
Product / "Osen" detachable seat heater

The Ulyanovsk heater's price seemed inflated at first: there is no automatics to speak of, just an ordinary switch like the one on a floor lamp. But where is the thermal switch promised by the instructions? Aha, there it is — found it! And playing the role of the heating element — the same old wiring wire.

Manufacturer / unnamed
Product / "Winter Delight" electrically heated seat pad

The maker of the "Winter Delight" pad, for some reason, chose not to sign its creation. In vain — it is a decent pad, no worse than the others. Pleasant velour, adjustable straps, no automatics, and the same wiring wire working essentially in short-circuit mode. Understandably, a single break inside and the product will promptly fail.

4. Manufacturer / TEPLODOM, Moscow
Product / "Emelya" electric heater

At last a proper heating element has been discovered — instead of wiring wires, the company has used carbon material! The narrow fibers are securely connected to the wires, which no longer have to double as heaters. Moreover, such a product will not fail even if one or several carbon strands happen to break — the rest will cover for them, though it will get somewhat colder...
The "part of the body in contact" is not the only power-on indicator — there is also an LED mounted on the plug.

5. Manufacturer / ASS-MEDIA research and production association
Product / Electrically heated car cover

Well, very expensive... Though made in a civilized way — pleasant material texture, springy fastening straps. Inside the cover — separate heating elements made of carbon composite.
Out of interest we decided to check the parameters of one of the heating elements labeled "12 volts, 12 watts." We measured the resistance cold and hot — it came out at 3 and 12 ohms respectively. Well, that is exactly right — in the working mode it works out to precisely 12 watts. And now we also know how much higher the inrush current is than the settled one — just for the record...

6. Manufacturer / VITOTEKHTORG LLC
Product / Electric heating of a car seat. AKA - an electric heater for a car seat.

In many ways similar to the previous product — springy straps, one-button control and so on. After an hour the product switches off automatically, and the controller memorizes the mode at which the product's last automatic shutdown occurred. Nevertheless, the instructions categorically forbid leaving it switched on — and rightly so.
Inside the heater is carbon composite: a tape heating element hermetically sealed in heat-resistant film.

So, how do you like our photo display? We have, of course, formed our own opinion of all the heaters listed. Appearance and ergonomics are all, generally speaking, subjective, but carbon composite as a heating element is still better than wiring wire: everyone should mind their own trade. That is why we are casting our "votes" for the products of TEPLODOM (photo 4), ASS-MEDIA (photo 5) and VITOTEKHTORG (photo 6). If you want to save money and have no trouble with the electronics — take the "Emelya". If you trust automatics — take a closer look at the more expensive products. Whether or not to heed our opinion, however, is up to the readers.

Text / Mikhail Kolodochkin