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Portable electric stoves or broilers are clean and flameless but potentially dangerous—here's how to avoid the danger—

When the heating element of a common electric stove "burns" out, the wire simply falls apart at one point.
 
The table-top electric "hot plate" has long been popular for the preparation of small meals, a pot of tea or coffee, etc. In the last few years it has grown into a very elaborate piece of machinery, capable of roasting a whole chicken or turkey, a husky piece of roast beef, a couple of pounds of steak, a rack full of hot dogs or 'burgers, etc.

The portable electric stove or broiler is clean, flameless, easy to handle and store. In its usual forms it is also, potentially, an extremely dangerous device. It must be treated with care because in nine cases out of ten the glowing coils of resistance wire that produce the desired heat are completely exposed. If the surface of a frying pan or any other metallic container touches any part of the wire, the vessel can readily become "hot" electrically as well as thermally. For this reason you should examine any such "cooker" at frequent intervals to make sure that the resistance wire is well below (or above, as the case might be) the insulated form in or on which it rests. The proverbial ounce of prevention here is worth many times the pound of cure. The    simplest    electric    stove    consists usually of a grid or helix of resistance wire set into a square or circular ceramic form. This in turn is supported by a stamped sheet iron frame with legs. The power rating runs between 500 and 750 watts for a single unit. A switch usually is not provided; to turn the unit on or off, you merely attach or remove the line cord connector.

Pull out the broken ends, twist them together tightly with pliers, and push the joint back into the ceramic form. Be sure it lies flat and does not stick up; it must never touch the bottom of pans.

When a metal salt shaker accidentally rolled under this hot plate, it short-circuited the resistance wires at the point where they join the connector   prongs.   To   repair,   splice   each   wire.

Make frequent tests on an electric stove for "grounds." Set the test meter for LO OHMS, connect one test prod to a pan on the stove, and touch the other test prod to each of the prongs of the attachment plug, in turn. If meter needle moves, pan is touching exposed wires. Push latter down into the ceramic form.

In hinged top broiler, resistance element is in dome, and radiates its heat downward to food on bottom rack. Ceramic grid is held by single screw in center, and is easily removed for cleaning or repair. Ceramic form actually contains two separate resistance coils, one for "low" heat, the other for "high."

Close-up of three-prong connector and two-prong attachment plug of hinged-top broiler shown above. Half of plug casing has been removed to reveal internal arrangement Center prongs always connect. As plug is flopped either way. the outer prong connects to either the "low" or the "high" heat resistance coil.

Figure 1: Connections of dual-heat broiler. "High" and "low" heat coils operate independently, but have common center connector prong, 1. Connector has two prongs. When A is on 1 and B on 2. only "low" coil is connected. When connector is turned over. B is on 3, only "high" coil functions.

Inside view of two-burner stove, with top pushed back to show connections to two switches and line cord. Switches are of double-pole, single throw type, with ceramic bodies to withstand heat.
 
Since the wire is in open view, it is easy to locate the break in it when it burns out. Pull out the parted ends carefully, twist them together with a pair of pliers, snip the joint short, and push the wire back into the form. The resistance element can be patched in this manner half a dozen times. However, if the stove has had a lot of service, the wire may become excessively brittle, and should be replaced by a new length. Hardware and electrical supply stores everywhere sell replacement wire, which is usually displayed on squares of cardboard.

Thread the new wire into the old grooves, and secure its ends under the nuts on the connector pins. Also clean the connector pins with sandpaper, while you're about it.

Using the Handitester or Clicktester, check for possible "grounding" of the heating wire. Put a pot or pan on the stove and connect one lead of the tester to it. With the connector plug in place, touch the other test prod to each of the prongs on the line cord plug, in turn. There should be absolutely no meter movement on LO OHMS or no sound in the earphone. If there is, the wire is poking up and is touching the bottom of the pot.
Some broilers have the resistance element mounted in a hinged top or dome, which can be closed down against a bottom pan to conserve the heat. They might also have two "heats," selected by a reversible connector as shown in Figure 1. There may be three connector prongs on the broiler itself, the center one common to two different resistance coils. With the connector in one position, one coil is energized; when it is flopped, the other comes on, and the first goes off. A typical broiler takes about 350 watts in "low" and 950 watts in "high."

Two-burner stoves permit two cooking operations to be performed at once. The two grids, working at different heats, are controlled by separate switches. As shown in Figure 2, these are usually of the double pole type, instead of the usual single pole variety found on most appliances. In their "off" positions, they completely disconnect the exposed resistance wires from the power line, so there is no danger of accidental "grounding" even with the attachment plug left in the wall outlet. This is a highly desirable safety measure, as far as it goes.

Two-burner table-top stove has separate "high" and "medium" heat units, which can be used separately or together. Continuity check is being made here.- no reading indicates an open wire.
 
In most cases, the break in the heating wire is visible, and can be repaired easily by twisting the open ends with pliers, as shown. Of course, always  make  sure  the  appliance  is  unplugged.

Figure 2: Internal connections of typical two-burner table-top stove. Coils can be used individually or together. Double-pole switches isolate coils completely from the power line when they are not in use.
 
The "high" element runs to about 1000 watts, the "medium" to 750. Both can be turned on at the same time. The current drain is then just about the safe technical maximum of 15 amperes for a No. 14 line.

Table-top broilers the size of a small trunk are almost the standard gift nowadays for a young married couple. Most of them include a motor-driven spit, heat control in two or more stages, and automatic timing. Basically, they still depend on a grid of resistance wire, which in practically all models is mounted just under the top of the gleaming case. The fact that it's almost out of sight mustn't fool you; it's very easy to poke a tray or dish into it if you're not careful.

Manufacturers are trying to outdo each other  in  fitting  out  their  broilers  with switches, knobs, buttons, controls of all kinds, shapes and colors. With the aid of the Handitester you can trace out the wiring pretty easily. Many of the connections in these appliances are of the sliding friction type, and can be pulled apart in an instant for convenience in tracing circuits, switches, pilot lights, etc.

Stove should be opened and cleaned out occasionally. Construction of unit is usually simple. Here, nut on long center bolt of heating element is being carefully loosened with an end wrench.
 
Heating element is fastened to top deck by another nut, on underside. It comes off in a jiffy with the aid of either a small wrench or a pair of pliers. Be careful in handling elements during disassembly.

When taking connections apart, be sure to identify them in some fashion to facilitate reassembly later. Tie knots in the wires or mark them with matching pieces of colored string, thread, tape, etc.

The resistance elements of these big broilers are quite accessible for inspection, repair, or replacement. They usually give little trouble. What requires more attention is the switching and timing mechanisms. These accumulate coatings of grease from meat prepared in the appliance, and eventually become pretty badly fouled. It may be necessary to degunk them with a generous application of carbon tetra-chloride or any similar noninflammable cleaning fluid. Caution: When using carbon tet, work near an open window and avoid breathing the fumes of the stuff. It's a wonderful grease solvent, but it's hard on the human system. (See also two pages following.)   ·

Heating element is now out. Opening in which it rests acts as catch pan for food drippings, and should be washed out thoroughly. Dry well before reassembling parts. New resistance wire, if   needed,   is   easily   inserted   in   ceramic   form.

In most table-top "broilers," heating element is on underside of lid. In well-made unit like this one. the wire is supported by series of closely spaced insulators. However, since wire runs near melting point, it is bound to droop. Inspect it frequently, and distribute it evenly in its supports with screwdriver blade.

Grounding test on large table-top broiler is very important safety precaution. Set meter to LO OHMS, and one test prod on metal frame. Touch other prod to each prong in turn. Needle should not move. Urgent suggestion: Remove present two-wire cord and replace by three-wire cord and polarized safety plug, with third wire connected anywhere to frame of broiler. Accidental "grounding" of resistance wire will then only blow the line fuse, and the user of the appliance will be protected against shock.

Accumulation of grease and food drippings on inner "works" of broiler makes periodic cleaning worthwhile. Appliance is usually assembled with nuts and bolts and self-tapping screws, and comes apart readily. Side member of this typical broiler is held by a single screw, here being removed.
 
Timer, motor switch and hi-lo heat switch are mounted on removed side of broiler; spit motor on side of frame. Motor usually is of shaded-pole (brushless) type and has two wires coming out of it. Amount of food "gunk" that seeps into motor and switches  of your broiler will  astonish you.

To remove motor completely for cleaning or replacement, take out mounting screws from inside. To keep them from going astray, keep all loose fasteners in box or cup. Clean before reassembly.
 
Spit motor is usually small high-speed unit fitted with reduction gear drive. Food drippings in latter can make it very stiff. Clean with carbon tetrachloride, at same time lubricate it sparingly.

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