A drip coffee maker consists of several components: 1. A heating element - combined or separate Calrod(tm, usually) types for operating the drip pump and then keeping the coffee warm. 2. Thermal protector - to prevent excess temperatures. 3. Some kind of water interlock - prevents dripping when separate reservoir is used. 4. Timer or controller. The simplest are mechanical while programmable units with clocks and electronic timers are also available. Many problems are be mechanical - clogged water passages or interlock. Extended use with hard/high mineral content water can also result in reduced heating effectiveness and/or increased heating times. It may be possible to flush the unit a couple of times with viniger. If there is no heating, check the element and thermal protector with an ohmmeter. If the element is open, it is probably time for a new coffee maker. The thermal protectors can be replaced but the underlying cause may be a defective, shorted overheating element so it may not be worth the trouble. Timers can develop bad contacts and bad connections are possible on electronic controller circuit board wiring.
(From: Niels Henriksen (ap294@FreeNet.Carleton.CA)). I wish I had thought of this sooner rather than throwing out the first coffee maker and I had planned to throw this one out. For some reason I thought I would just look inside to see what was up. Where I live the water is hard (well) and there is constant scaling and buildup of calcium. We heard that all you have to do is to run a mixture of vinegar through the coffee maker to rejuvenate. A friend and the 2 of ours all started to leak very badly when the vinegar/water mixture when through. I though that the internal plumbing had corroded through the metal parts and the vinegar dissolved the calcium that was protecting the holes and therefore unrepairable. Who knows where these ideas come from. Now for the technical solution. The element that is used to boil the water and uses the bubbles to bring hot water to top of coffee maker is the same element that is used to keep the pot warm. There is a metal tube attached to the metal warming element and this unit has a heating element embedded. There are 2 rubber hoses attached. One brings cold water to heater and the other brings boiling water to top. The cold water tube has a check valve that prevents the bubbling water from going to cold water reservoir. When vinegar is added the calcium scales start to dissolve and in 3 of 3 so far, this blocked the metal tube. The water starts to boil and since the cold water inlet has a check valve the water pressure can only buildup to where the rubber tube is blown off the metal pipe. No damage to parts. To fix: 1. Take bottom off to gain access to heater area. 2. Remove rubber tubes which are connected with spring clamps. 3. Run rubber tubes through your fingers to loosen scale buildup and flush out 4. push a thin copper wire or other bendable wire through heating tube. This is to unblock and loosen some scale. 5. Pour straight vinegar into metal tube to dissolve calcium and use wire to loosen. 6. Repeat several times till clean. 7. Re-attach all parts and use. The solution is to start a regular process of using vinegar BEFORE the calcium has buildup to the point where when loosened it will block the tube.
While largely replaced by the drip coffee maker, these are still available, particularly in large sizes. The components are similar to those in a drip coffee maker - element, thermal protector, possibly a thermostat as well. The element and bottom of the water/coffee container are likely one piece to provide the best thermal conduction for the 'pump' in the middle. Even if the element is removable, it may not be worth the cost of replacement except for a large expensive unit.
These consist of a heating element, thermal protector, and possibly a thermostat and/or timer. See comments for coffee makers.
While line operated clocks have mostly been superseded by electronic (LED or LCD) clocks on nearly every kitchen appliance, many of these are still in operation on older clock radios and ranges. AC operated clocks depend on the AC line frequency (60 Hz or 50 Hz depending on where you live) for time keeping. The accuracy of a line operated clock is better than almost any quartz clock since the long term precision of the power line frequency is a very carefully controlled parameter and ultimately based on an atomic clock time standard. Therefore, most problems are related to a clock motor that does not run or will not start up following a power outage. Once running, these rarely fail. The most common problems are either gummed up oil or grease inside the motor and gear train, broken gears, or broken parts of the clock mechanism itself. See the sections on "Synchronous timing motors" for repair info. Battery operated quartz clocks usually operate on a 1.5 V Alkaline cell (do not replace with NiCds as they do not have a long absolute life between charges even if the current drain is small as it is with a clock). First, test the battery. Use a multimeter - usually anything greater than 1 V or so will power the clock though if it is closer to 1 V than 1.5 V, the battery is near the end of its life. The clock may run slow or fast or erratically on a low battery. With a good battery, failure to run properly is usually mechanical - one of the hands is hitting against the glass front or something like that. Don't forget to check any on/off switch - these are not expected but are often present presumably to permit you to start the clock at precisely the right time. I had one case where the fine wire to the solenoid that operates the once per second clock mechanism broke and had to be resoldered but this is exceedingly rare. If the clock consistently runs slow or fast with a known good battery, there is usually a trimmer capacitor that can be adjusted with a fine jeweler's straight blade screwdriver. Without test equipment the best you can do is trial and error - mark its original position and turn it just a hair in one direction. Wait a day or week and see if further adjustment is needed (right, like you also won the lottery!) and fine tune it. If the hands should fall off (what a thought!), they can usually be pressed back in place. Then, the only trick is to line up the alarm hand with the others so that the alarm will go off at the correct time. This can usually be done easily by turning the hour hand counterclockwise using the setting knob in the rear until it is not possible to turn it further. At this point, it is lined up with the alarm hand. Install all hands at the 12:00 position and you should be more or less all set.
The mechanism consists of a shaded pole induction motor and gear train. Clean and lubricate the gears. See the section: "Shaded pole induction motors" for motor problems.
There consist of a shaded pole induction motor, gear train. and power switch. Likely problems relate to broken gear teeth, dirty or worn power switch, dull cutting wheel, and broken parts. Lubrication may be needed if operation is sluggish. Parts that come in contact with the cans and lids collect a lot of food grime and should be cleaned frequently.
A small motor operates a pair of reciprocating mounts for the blades. AC powered carving knives include a momentary power switch, small motor (probably universal type), and some gearing. Congealed food goo as well as normal lubrication problems are common. The power switch is often cheaply made and prone to failure as well. The cord may be abused (hopefully not cut or damaged by careless use of the knife!) and result in an intermittent connection at one end or the other. For motor problems, see the appropriate sections on universal motors. For battery powered knives, bad NiCds cells are a very likely possibility due to the occasional use of this type of appliance. See the section: "Small permanent magnet DC motors" and the chapter: "Batteries" for information on repair.
Similar to electric carving knives except for the linkage to the blades. All other comments apply.
These consist of a universal motor which usually features a continuously variable speed control or a selection of 3 to 5 speeds, a gearbox to transfer power to the counter-rotating beaters, and a power switch (which may be part of the speed control). Sluggish operation may be due to cookie dough embedded in the gearing. Fine particles of flour often find their way into the gears - clean and lubricate. There may be a specific relationship that needs to be maintained between the two main beater gears - don't mess it up if you need to disassemble and remove these gears or else the beaters may not lock in without hitting one-another. The speed control may be a (1) selector switch, (2) mechanical control on the motor itself, or (3) totally electronic. Parts may be replaceable although, for portables at least, a new mixer may make more sense. For sluggish operation (non-mechanical), sparking, burnt smells, etc., see the section: "Problems with universal motors".
A powerful universal motor is coupled to interchangeable cutters of various types. In most respects, food processors are similar to any other universal motor driven appliance with one exception: There will be a safety interlock switch to prevent operation unless the cover is on properly and secured. This switch may go bad or its mechanical position adjustment may shift over time resulting in difficulty in engaging power - or a totally dead unit. As usual, cord and plug problems, bad bearings, burnt motor windings, and broken parts are all possibilities.
Most modern irons (does anyone really use these anymore?) can be used dry or with steam. An iron consists of a sole plate with an integrated set of heating coils. Steam irons will have a series of holes drilled in this plate along with a steam chamber where a small amount of water is boiled to create steam. A steam iron can be used dry by simply not filling its reservoir with water. Those with a spray or 'shot of steam' feature provide a bypass to allow hot water or steam to be applied directly to the article being ironed. Over time, especially with hard water, mineral buildups will occur in the various passages. If these become thick enough, problems may develop. In addition, mineral particles can flake off and be deposited on the clothes. A thermostat with a heat adjustment usually at the top front of the handle regulates the heating element. This is usually a simple bimetal type but access to the mechanism is often difficult. Where an iron refuses to heat, check the cord, test the heating element for continuity with your ohmmeter, and verify that the thermostat is closed. An iron that heats but where the steam or spray features are missing, weak, or erratic, probably has clogged passages. There are products available to clear these. Newer irons have electronic timeout controllers to shut the iron off automatically if not used for certain amount of time as a safety feature. Failure of these is not likely and beyond the scope of this manual in any case. When reassembling an iron, take particular care to avoid pinched or shorted wires as the case is metal and there is water involved - thus a potential shock hazard.
In addition to a fine heating element, there is a controller to determine the length of time that the bread (or whatever) is heated. A solenoid or bimetal trip mechanism is used to pop the bread up (but hopefully not totally out) of the toaster then it is 'done' and turn off the heating element at the same time. Since most of these are so inexpensive, anything more serious than a broken wire or plug is probably not worth repairing. The heating element may develop a broken spot - particularly if something like a fork is carelessly used to fish out an English muffin, for example. (At least unplug it if you try this stunt - the parts may be electrically live, your fork is metal, you are touching it!). They may just go bad on their own as well. Being a high current appliance, the switch contacts take a beating and may deteriorate or melt down. The constant heat may weaken various springs in either the switch contact or pop-up mechanism as well. Sometimes, some careful 'adjustment' will help. Controllers may be thermal, timer based, or totally electronic. Except for obvious problems like a bent bimetal element, repair is probably not worth it other then as a challenge.
If it really is old, then your problem is almost certainly mechanical - a spring sprung or gummed up burnt raisin bread. You will have to do a little investigative research meaning: take the thing apart! Try to determine what the bread does to cause the support to drop down. It is possible that putting the bread in is supposed to trip a microswitch which activates a solenoid, and the switch or solenoid is now defective - bad contacts or broken wires, bad coil in the solenoid, or grime. The following applies directly to several Sunbeam models (and no doubt to many others as well). (From: John Riley (firstname.lastname@example.org)). I will assume that the toaster is either a model ATW or possibly an older model 20 or the like. When you drop the bread in the toaster it trips a lever that is attached to the bread rack. This lever pushes in on the contacts inside of the thermostat (color control switch) which actually turns the toaster on. In "most cases" adjusting the screw on the bottom of the toaster will do the trick. The proper adjustment is to adjust the carriage tension so that the bread rack in the side where it marked for a single slice of bread comes just to the uppermost limit of its travel. Any more is overkill. If you have adjusted it as mentioned above and it still won't go down, there is one more thing you can try. Take the toaster a sort of BUMP it down onto the table rather firmly. Sometimes a piece of crumb will get in between the thermostat contacts. A couple of good "bumps" on the table will usually dislodge the particle. If all of the above doesn't work, and you know the cord isn't bad, them you may very well have a thermostat that has gone south. They are still available for replacement on most models. Suggest you check with your local SUNBEAM AUTHORIZED SERVICE for price and availability.
I really liked the old original style GE toaster oven. It was very versatile and convenient for baking and toasting. The newer types seem to have lost some of these qualities. The pop open door and oven tray have apparently not been retained in any modern models that I am aware of. Modern toaster oven (broilers) use Calrod style elements - usually two above and two below the food rack. Depending on mode, either just the top (top brown/broil), just the bottom (oven), or both sets (toast) will be energized. Each pair may be wired in series meaning that a failure of one will result in both of the pair being dead. Very old units may use a coiled NiChrome element inside a quartz tube. Thermostats are usually of the bimetal strip variety with an adjustment knob. A cam or two on the shaft may also control main power and select the broil function in the extreme clockwise position. There may be a mode switch (bake-off-broil) which may develop bad contacts or may fuse into one position if it overheats. These are often standard types and easily replaceable. Just label where each wire goes on the switch before removing it to take to an appliance repair parts store. Newer models may use an electronic timer for the toast function at least. I assume it is not much more than something like an IC timer (555) operating the trip solenoid. However, I have not had to deal with a broken one as yet. Testing is relatively straightforward. Check the heating elements, thermostat, mode switch,, cord, and plug. While replacements for heating elements and thermostats are often available, removing the old one and wiring the new one may not be straightforward - rivets may be used for fastening and welds for the wire connections. You will have to drill the rivets with an electric drill and replace them with nuts, bolts, and lockwashers. Crimp splices or nuts and bolts can be used for the wiring. Take extra care in reassembly to avoid any bare wires touching the metal cabinet or other parts as well as insulation being cut by sharp sheetmetal parts. The high temperature fiberglas or asbestos insulation is not very robust. In the end, it may not be worth it with full featured toaster oven/broilers going for $20-30 on sale.
Unlike a regular (non-microwave) oven, convection ovens are not totally silent. There is a small fan used to circulate the hot air (thus the name: convection oven). Depending on the oven's design and age, these fans may be anywhere from nearly silent to objectionably noisy. If you notice an increase in motor noise (whining or squealing, grinding, knocking) then the motor and fan should be inspected and parts replaced if necessary. Sudden failure is unlikely but if it were to happen - seized bearings, for example - an overtemperature thermal protector should shut down the heating element or entire oven. Some of these may not be self resetting (thermal fuse).
These are all just a single or dual heating element, thermal protector (not all will have one), and an adjustable (usually) thermostat. As usual, check the cord and plug first, and then each of the other parts with an ohmmeter. Where a NiChrome coil type heating element is used, a break will be obvious. If it is very near one end, then removing the short section and connecting the remainder directly to the terminal will probably be fine. See the section: "Repair of broken heating elements". For appliances like waffle irons, burger makers, and similar types with two hinged parts, a broken wire in or at the hinge is very common. Note that since these operate at high temperatures, special fiberglass (it used to be asbestos) insulated wiring is used. Replace with similar types. Take extra care in reassembly to avoid shorted wires and minimize the handling and movement of the asbestos or fiberglas insulated high temperature wiring.
An Oil popper is basically an electric frying pan with a built-in stirrer and cover. The internal parts are accessed from the bottom: Heating coil, thermostat and thermal protector, and small gear-motor similar to that used in a clock or timer. Take care to note the orientation of the motor when removing and to not damage any seals (you don't want oil seeping down under!). As always, check for bad connections if the popper is dead or operation is erratic. Problems with heating can arise in the heating element, thermostat, and thermal protector. If the stirrer doesn't turn, a gummed up motor or stirrer shaft (since these are only used occasionally) may be the problem. See the chapter: "Motors 101".
Air poppers combine a heating element and blower to heat corn kernels without the need for any unhealthy oil. Of course, you probably then drown the popcorn in butter and salt, huh? Admit it! :-). As always, check for bad connections if the popper is dead or operation is erratic. Problems with heating can arise in the heating element, thermostat, and thermal protector. The motor is probably a small PM DC type and there will then be a set of diodes or a bridge rectifier to turn the AC into DC. Check these and for bad bearings, gummed up lubrication, or other mechanical problems if the motor does not work or is sluggish. See the chapter: "Motors 101".
Moth mechanical and electrical problems are possible. (Note: we are not going to deal with fancy computerized equipment as this is probably better left to a professional except for the more obvious problems like a bad cord or plug.) I have a 1903 Singer foot-pumped sewing machine which we have since electrified and still runs fine. A couple of drops of sewing machine or electric motor oil every so often is all that is needed. They were really built well back then. Although the appearance of the internal mechanism may appear intimidating at first, there really is not that much to it - a large pulley drives a shaft that (probably) runs the length of the machine. A few gears and cams operate the above (needle and thread) and below (feet and bobbin) deck mechanisms. Under normal conditions, these should be pretty robust. (Getting the adjustments right may be another story - refer to your users manual). Sometimes if neglected, the oil may seriously gum up and require the sparing use of a degreaser to loosen it up and remove before relubing. If the motor spins but does not turn the main large pulley, the belt is likely loose or worn. The motor will generally be mounted on a bracket which will permit adjustment of the belt tension. The belt should be tight but some deflection should still occur if you press it gently in the middle. If the motor hums but nothing turns, confirm that the belt is not too tight and/or that the main mechanisms isn't seized or overly stiff - if so, it will need to be cleaned and lubrication (possibly requiring partial disassembly). The electric motor is normally a small universal type on a variable speed foot pedal (see the section: "Wiring a sewing machine speed control"). If the motor does not work at all, bypass the foot pedal control to confirm that it is a motor problem (it is often possibly to just plug the motor directly into the AC outlet). Confirm that its shaft spins freely. All normal motor problems apply - bad wiring, worn brushes, open or shorted windings, dirty commutator. See the section: "Problems with universal motors".
This assumes a basic sewing machine (nothing computer controlled) with a normal universal series wound motor (115 VAC). The common foot pedals are simply wirewound rheostats (variable resistors) which have an 'off' position when the pedal is released. They are simply wired in series with the universal motor of the sewing machine (but not the light) and can be left plugged in all the time (though my general recommendation as with other appliances is to unplug when not in use. While not as effective as a thyristor type speed controller, these simple foot pedals are perfectly adequate for a sewing machine. There are also fancier speed controls and using a standard light dimmer might work in some cases. However, there are two problems that may prevent this: the sewing machine motor is a very light load and it is a motor, which is not the same as a light bulb - it has inductance. The dimmer may not work, may get stuck at full speed, or may burn out.
A variety of types of drive mechanisms are used in electric shavers: 1. Vibrator (AC only) - these (used by Remington among others) consist of a moving armature in proximity to the pole pieces of an AC electromagnet. The mass and spring are designed so that at the power line frequency, the armature vibrates quite strongly and is linked to a set of blades that move back and forth beneath the grille. If dead, check for continuity of the plug, cord, switch, and coil. IF sluggish, clean thoroughly - hair dust is not a good lubricant. Sliding parts probably do not require lubrication but a drop of light oil should be used on any rotating bearing points. Note that since a resonance is involved, these types of shavers may not work well or at all on foreign power - 50 Hz instead of 60 Hz or vice versa - even if the voltage is compatible. 2. Universal motor (AC or DC) - very small versions of the common universal motors found in other appliances. A gear train and linkage convert the rotary motion to reciprocating motion for shavers with straight blades or to multiple rotary motion for rotary blade shavers. These may suffer from all of the afflictions of universal motors; bad cords, wires, and switches; and gummed up, clogged, or worn mechanical parts. Also see the sections on the appropriate type of motor. Take care when probing or disassembling these motors - the wire is very fine any may be easily damaged - I ruined an armature of a motor of this type by poking where I should not have when it was running - ripped all the fine wires from the commutator right off. 3. DC PM motor - often used in rechargeable shavers running of 2 or 3 NiCd cells. These may suffer from battery problems as well as motor and mechanical problems. One common type is the Norelco (and clone) rotary shaver. See the chapters on Batteries and AC Adapters as well as the sections on "Small permanent magnet DC motors". A shaver that runs sluggishly may have a dead NiCd cell - put it on charge for the recommended time and then test each cell - you should measure at least 1.2 V. If a NiCd cell reads 0, it is shorted and should be replaced (though the usual recommendation is to replace all cells at the same time to avoid problems in the future). Note that in terms of rechargeable battery life, shavers are just about optimal as the battery is used until it is nearly drained and then immediately put on charge. The theoretical 500 to 1000 cycle NiCd life is usually achieved in shaver applications.
These are basically similar to any other small battery operated appliance or tool such as a screwdriver or drill. The permanent magnet motor runs off of rechargeable NiCd batteries and cause the bristles or whatever to oscillate, rotate, or vibrate. Interchangeable 'brush' units allow each member of the family to have their own. Problems can occur in the following areas: * Motor, battery pack, connections, on/off switch - as with any other similar device. * Power train - gummed up lubrication, broken, or other mechanical problems. * Charging station or circuitry - the fault may be with the base unit or circuitry associated with the battery pack. See the section: "Braun electric toothbrush repair", below. Since these must operate in a less than ideal environment (humid or actual waterlogged!), contamination and corrosion is quite possible if the case is not totally sealed. Some of the switched may be of the magnetic reed type so that there don't need to be any actual breaks in the exterior plastic housing. Of course, getting inside may prove quite a challenge: (From: Jeff & Sandy Hutchinson (email@example.com)). It's darned near impossible to replace the batteries on the Interplak toothbrush without destroying the recharging circuit. The base of the hand unit has a little pickup coil in it, and when you unscrew the cap to get at the batteries, you break the connections to the pickup coil. Best to do an exchange with the factory.
(From: David DiGiacomo (dd@Adobe.com)). This Braun electric toothbrush (original model) would turn itself on and keep running until its batteries were discharged. The toothbrush can be disassembled by pulling the base off with slip joint pliers (do not pull too hard because there is only about 1" of slack in the charging coil wires). With the base off, the mechanism slides out of the case. There is a simple charging circuit, charging LED, 2 NiCd cells, and a reed switch driving the base of an NPN transistor. The transistor collector drives the motor. I charged the battery, but the problem of the motor running with the reed switch open didn't recur until I held my finger on the transistor for about 10 seconds seconds. Grounding the transistor base turned it off again, and I could repeat this cycle. Since there wasn't anything else to go wrong I decided to replace the transistor. I couldn't read the marking, but it's in a SOT89 package and the motor current is 400-700 mA so it must be something like a BC868. However, I didn't have any surface mount or TO92 transistors that could handle the current, so I used a 2SD882 (small power tab package), which I was able to squeeze into some extra space in the center of the charging coil.
These are simply motors with an off-axis (eccentric) weight or electromagnetic vibrators. If the unit appears dead, check the plug, cord, on/off switch, internal wiring, and motor for continuity. Confirm that the mechanical parts turn or move freely. Some have built in infra-red heat which may just be a set of small light bulbs run at low voltage to provide mostly heat and little light (a filter may screen out most of the light as well). Obviously, individual light bulbs can go bad - if they are wired in series, this will render all of them inert. At least one brand - Conair - has had problems with bad bearings. Actually, poorly designed sleeve bearings which fail due to the eccentric load. If you have one of these and it becomes noisy and/or fails, Conair will repair (actually replace) it for $5 if you complain in writing and send it back to them. They would like a sales receipt but this apparently is not essential.
A heating element - usually of the NiChrome coil variety - is combined with a multispeed centrifugal blower. First determine if the problem is with the heat, air, or both. For heat problems, check the element for breaks, the thermal protector or overtemperature thermostat (usually mounted in the air discharge), the connections to the selector switch, and associated wiring. For air problems where the element glows but the fan does not run, check the fan motor/bearings, connections to selector switch, and associated wiring. Confirm that the blower wheel turns freely and is firmly attached to the motor shaft. Check for anything that may be blocking free rotation if the blower wheel does not turn freely. The motor may be of the induction, universal, or PM DC type. For the last of these, a diode will be present to convert the AC to DC and this might have failed. See the appropriate section for problems with the type of motor you have.Go to [Next] segment
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