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This means the fan runs but you do not hear the compressor kick in. It could be several things: * If you hear the 'click' of the thermostat but nothing happens (Your room lights do not dim even for a second) and there is no other sound, it could be bad connections, bad thermostat, dirty switch contacts, bad compressor, etc. Or, you have it set on fan instead of cool. Try cycling the mode selector switch a couple times. * If you do not hear a click at all, then the thermostat is probably bad or it is cooler in your room than you think! Try tapping on the thermostat. Sometimes they just stick a bit after long non-use. * If you get the click and the lights dim and then a few seconds later there is another click and the lights go back to normal, the compressor, or its starting circuitry is bad. It is trying to start but not able to get up to speed or rotate at all. Except for a bad compressor, all these are repairable relatively inexpensively but if it is real old, a new high efficiency model may be a better solution.
When this happens, airflow is reduced greatly since ice is blocking the evaporator. Turning the unit off for a while or running it on fan-only will clear the ice but this may indicate the need for maintenance or an actual problem. Similar comments apply to window and central air conditioners as well as heat pumps. The three major causes of an air conditioner freezing up are: 1. Reduced airflow due to a dirty filter or clogged evaporator. If you are not aware that there is a filter to clean, this is probably the cause :-). 2. Low Freon. While your intuition may say that low Freon should result in less cooling, what happens is that what is there evaporates too quickly and at the input end of the evaporator coils resulting in lower temperatures than normal at that end (which results in condensed water vapor freezing instead of dripping off) but part of the evaporator will likely be too warm. You cannot fix this yourself without specialized equipment. For a room air conditioner that isn't too old, it may be worth taking it in to a reputable shop for an evaluation. For a central air conditioner, you will have to call an HVAC service company for repairs. The fact that the Freon is low means that there is a leak which would also need to be repaired. Freon does not get used up. 3. Outside and/or inside temperature may be very low. The unit may not be designed to operate below about 65 degrees F without freezing up. If it is 90 degrees F and you have full air flow with the fan set on high and still get the freezup on a part of the evaporator, then low Freon is likely.
For quite a lot of useful information, do a web search for 'appliance repair'. There are a couple of decent sites with DYI information. (From: Bernie Morey (bmorey@aardvark.apana.org.au)). I've repaired our electric dryer several times over the years and kept it going well beyond its use-by date. My main problems have been: 1. Mechanical timer failure. Easy fix. 2. Leaking steam damaging the element. Have replaced element twice -- fairly easy job. Had to replace some stainless stand-offs at the same time. Elements readily available and equivalent of USD24 each. 3. Bearing replacement -- have to be done carefully or they don't last. 4. Belt replacement. (Make sure you center the belt with respect to the idler and rotate the drum by hand to double check it before buttoning things up. Else, it may pop off the first time the motor starts. --- sam). 5. Exhaust fan bearing replacement. This was the trickiest, although far from impossible. It is a sealed unit subject to high heat and dust contamination -- not a good environment. The only problem for the past two years has been the dryer throwing the exhaust fan belt. Cleaning up the fluff fixes it for another year. Did all these without any guide -- just carefully inspecting the work before starting and making diagrams of wiring and ESPECIALLY the main drum belt. I generally have to get my wife to help me with the main belt -- hard to get the tensioner in position while stopping the belt slipping down the far side of the drum. These things are mechanically and electrically pretty simple -- if it's not working the fault is usually obvious.
There are multiple thermostats in a dryer - one that sets the air temperature during normal operation (and controls power to the heating element) and one or more that sense fault conditions (and may shut everything down) such as those described below. (From: Bernie Morey (bmorey@aardvark.apana.org.au)). The dryer is likely cutting out because a thermostat is tripping. The fundamental reason is probably that the exhaust air is too hot. And the air flow is probably too hot because it is restricted -- lower volume of air at higher temperature. Check these things out: 1. Lint filter. Although these can look clean (and I assume you do clean it after every load!) the foam variety can gradually clog up with very fine dust and restrict air flow. If it's a foam disk, a new one is fairly cheap. 2. Can you feel the exhaust air? If not, the exhaust fan belt may be worn broken or slipping. The exhaust fan bearing could be partly seized -- try turning the fan by hand and check for stiffness. 3. Air outlet blockage. Lint and dust may have built up in the exhaust side of the machine. Check for restrictions. Our machine just vents up against the laundry wall as it is too difficult to vent it to the outside. Outside vents are often plastic tubing with a spiral spring steel coil for stiffness -- check for kinks or obstructions. 4. 'Clutching at straws' Dept #1: Element may have developed a hot-spot near a thermostat. Involves dismantling the machine and checking the element. NB -- if you dismantle the machine, make a diagram of how the drive belt fits over the drum, motor, and idler! 5. 'Clutching at straws' Dept #2: The drum may be restricted from turning freely. This would slow the motor and hence the exhaust fan. Check for socks, women's knee-highs (these thing seem to breed everywhere!) & caught near the bearings (probably the front). You cannot completely check the thermostat with a meter -- they are either open or closed. To test it properly you would have to know the temperature at which it opens (from the manufacturer's specs), and then measure the temperature of the exhaust air with a probe while watching the thermostat.
This sort of failure is not unusual. The brass (or whatever) corrodes a bit over time and/or the prongs loosen up. It doesn't take much resistance at 20 or 30 Amps to produce a substantial amount of heat. The hotter it gets, the more the resistance goes up, heating increases, it loosens more, and so on until something melts. The power is I*I*R (where I is current and R is the resistance) so at 20 A, a .1 ohm resistance at the contact results in 40 W - think of the heat of a 40 W light bulb. An exact cause would be hard to identify. However, only the plug and receptacle are involved - this is not a case of an outside cause. Such a failure will not normally blow a fuse or trip a breaker since the current does not increase - it is not a short circuit. It is definitely wise to replace both the plug and receptacle in such cases since at the very least, the socket has lost its springiness due to the heating and will not grip well.. Make sure that the prongs on the new plug make a secure fit with the socket. On plugs having prongs with a pair of metal strips, spreading them out a bit will make much better contact in an old receptacle. In general, if a plug is noticeably warm, corrective action should be taken as it will likely get worse. Cleaning the prongs (with 600 grit sandpaper) and spreading the metal strips apart (if possible) should be done first but if this does not help much, the plug and/or socket should be replaced. Sometimes, the original heating problem starts at the wire connections to the plug or socket (even inside molded units) - loose screws, corroded wires, or deteriorated solder joints.
Why is it on a GFCI in the first place? A grounded outlet is all the protection that is needed and any type of appliance with a motor or transformer could be a potential nuisance tripper with a GFCI (though not always). As to why it is now different, I assume that this is a dedicated outlet so nothing else you added could affect it. Thus you are left with something changing in the dryer or the GFCI somehow becoming overly sensitive. It is possible that there is now some electrical leakage in the dryer wiring just from accumulated dirt and grime or dampness. This could be measured with an AC milliamp meter or by measuring the resistance between the AC wires and the cabinet. If this test shows up nothing, I would recommend just putting on a grounded outlet without a GFCI. It could also be that due to wear, the motor is working harder at starting resulting in just a tad more of an inductive current spike at startup.
(From: Filip "I'll buy a vowel" Gieszczykiewicz (filipg@repairfaq.org)). Greetings. Well, since it's a moist/damp environment... I'd suspect a bad connection first. You will need to pop off the front bottom panel and get at the wires that actually connect the solenoid to the timer motor (and/or wire harness). You will need an ohmmeter to check the resistance of the coil - if it's OK (20-200 ohms I would guess), that's not the problem. Well, that leaves you with pretty much the wires that connect the timer motor (a MULTI-contact switch driven by a timer motor like those found in old clocks that plugged into outlets) and the switch itself. I hope the dishwasher is unplugged... Since the dishwasher operates as a closed system (because of the "darned" water :-) it will be difficult to test it in circuit. I suggest that you try to trace the wires that come off the solenoid to their other ends... and then test the wires themselves. If you feel this is too much for you, call the repair folks - ask around... see if anyone else knows a particular service that has a good record...
This chapter is in no way intended to be a comprehensive coverage of wiring issues but includes a discussion of a few of the common residential wiring related questions. For more information, see the official Usenet Electrical Wiring FAQ or a DIY book on electrical wiring. The NEC (National Electrical Code) handbook which is updated periodically is the 'bible' for safe wiring practices which will keep honest building inspectors happy. However, the NEC manual is not what you would call easy to read. A much more user friendly presentation can be found at the CodeCheck web site: * http://www.codecheck.com/ This site includes everything you always wanted to know about construction codes (building, plumbing, mechanical, electrical) but were afraid to ask. In particular, the following series of sections on Ground Fault Circuit interrupters is present at the CodeCheck web site and includes some nice graphics as well.
A Ground Fault Circuit Interrupter (GFCI) is a device to protect against electric shock should someone come in contact with a live (Hot) wire and a path to ground which would result in a current through his/her body. The GFCI operates by sensing the difference between the currents in the Hot and Neutral conductors. Under normal conditions, these should be equal. However, if someone touches the Hot and a Ground such as a plumbing fixture or they are standing in water, these currents will not be equal as the path is to Ground - a ground fault - and not to the Neutral. This might occur if a short circuit developed inside an ungrounded appliance or if someone was working on a live circuit and accidentally touched a live wire. The GFCI will trip in a fraction of a second at currents (a few mA) well below those that are considered dangerous. Note that a GFCI is NOT a substitute for a fuse or circuit breaker as these devices are still required to protect equipment and property from overloads or short circuits that can result in fire or other damage. GFCIs can be installed in place of ordinary outlets in which case they protect that outlet as well as any downstream from it. There are also GFCIs that install in the main service panel. Note that it may be safe and legal to install a GFCI rated at 15 A on a 20 A circuit since it will have a 20 A feed-through. Of course, the GFCI outlet itself can then only be used for appliances rated 15 A or less. Many (if not most) GFCIs also test for a grounded neutral condition where a low resistance path exists downstream between the N and G conductors. If such a situation exists, the GFCI will trip immediately when power is applied even with nothing connected to the protected outlets.
A GFCI is NOT a substitute for a fuse or circuit breaker (unless it is a combined unit - available to replace circuit breakers at the service panel). Therefore, advice like "use a GFCI in place of the normal outlet to prevent appliance fires" is not really valid. There may be some benefit if a fault developed between Hot and Ground but that should blow a fuse or trip a circuit breaker if the outlet is properly wired. If the outlet is ungrounded, nothing would happen until someone touched the metal cabinet and an earth ground simultaneously in which case the GFCI would trip and provide its safety function. See the section: "Why a GFCI should not be used with major appliances" for reasons why this is not generally desirable as long as the appliance or outlet is properly grounded. However, if a fault occurs between Hot and Neutral - a short in the motor, for example - a GFCI will be perfectly happy passing almost any sort of overload current until the GFCI, wiring, and appliance melts down or burns up - a GFCI is not designed to be a fuse or circuit breaker! That function must be provided separately.
GFCIs typically test for the following condition: 1. A Hot to Ground (safety/earth) fault. Current flows from the Hot wire to Ground bypassing the Neutral. This is the test that is most critical for safety. 2. A grounded neutral fault. Due to miswiring or a short circuit, the N and G wires are connected by a low resistance path downstream of the GFCI. In this case, the GFCI will trip as soon as power is applied even if nothing is connected to its protected (load) circuit. To detect a Hot to Ground fault, both current carrying wires pass through the core of a sense coil (transformer). When the currents are equal and opposite, there is no output from its multiturn sense voltage winding. When an imbalance occurs, an output signal is produced. When this exceeds a threshold, a circuit breaker inside the GFCI is tripped. GFCIs for 220 VAC applications need to monitor both Hots as well as the Neutral. The principles are basically the same: the sum of the currents in Hot1 + Hot2 + Neutral should be zero unless a fault exists. To detect a grounded neutral fault, a separate drive coil is continuously energized and injects a small 120 Hz signal into the current carrying conductors. If a low resistance path exists between N and G downstream of the GFCI, this completes a loop (in conjunction with the normal connection between N and G at the service panel) and enough current flows to again trip the GFCI's internal circuit breaker. GFCIs use toroidal coils (actually transformers to be more accurate) where the core is shaped like a ring (i.e., toroid or doughnut). These are convenient and efficient for certain applications. For all practical purposes, they are just another kind of transformer. If you look inside a GFCI, you will find a pair of toroidal transformers (one for H-N faults and the other for N-G faults as described above). They look like 1/2" diameter rings with the main current carrying conductors passing once through the center and many fine turns of wire (the sense or drive winding) wound around the toroid. All in all, quite clever technology. The active component in the Leviton GFCI is a single chip - probably a National Semiconductor LM1851 Ground Fault Interrupter. For more info, check out the specs at National'a web site at: http://www.national.com/pf/LM/LM1851.html.
To detect a Neutral to Ground fault there is a second transformer placed upstream of the H-G sense transformer (see the illustration of the internal circuitry of the GFCI at: http://www.national.com/pf/LM/LM1851.html). A small drive signal is continuously injected via the 200 T winding which induces equal voltages on the H and N wires passing through its core. * If N and G are separate downstream (as they should be), no current will be flow in either wire and the GFCI will not trip. (No current will flow in the H wire as a result of this stimulus because the voltage induced on both H and N is equal and cancels.) * If there is a N-G short downstream, a current will flow through the N wire, to the G wire via the short, and back to the N wire via the normal N-G connection at the service panel. Since there will be NO similar current in the H wire, this represents a current unbalance and will trip the GFCI in the same manner as the usual H-G short. * Interestingly, this scheme automatically detects a H-H fault as well. This unlikely situation could occur if the Hots from two separate branch circuits were accidentally tied together in a junction box downstream of the GFCI. It works the same way except that the unbalance in current that trips the GFCI flows through the H wire, through the H-H fault, and back around via the Hot busbar at the service panel. Of course if the two Hots are not on the same phase, there may be fireworks as well :-).
Despite the fact that a Ground Fault Circuit Interrupter (GFCI) may be installed in a 2 wire circuit, the GFCI does not create a safety ground. In fact, shorting between the Hot and Ground holes in the GFCI outlet will do absolutely nothing if the GFCI is not connected to a grounded circuit (at least for the typical GFCI made by Leviton sold at hardware stores and home centers). It will trip only if a fault occurs such that current flows to a true ground. If the original circuit did not have a safety ground, the third hole is not connected. What this means is that an appliance with a 3 prong plug can develop a short between Hot and the (supposedly) grounded case but the GFCI will not trip until someone touches the case and an earth ground (e.g., water pipe, ground from some other circuit, etc.) at the same time. Note that even though this is acceptable by the NEC, I do not consider it desirable. Your safety now depends on the proper functioning of the GFCI which is considerable more complex and failure prone than a simple fuse or circuit breaker. Therefore, if at all possible, provide a proper Code compliant ground connection to all outlets feeding appliances with 3 wire plugs.
If you move into a house or apartment where some or all of the outlets are the old 2 prong ungrounded type, don't panic. There is no reason to call an electrician at 2:00 AM in the morning to upgrade them all at great expense. You don't need grounded outlets for two wire appliances, lamps, etc. They do essentially nothing if the third hole isn't occupied :-). A GFCI will provide much more protection! You should have grounded outlets for the following: * Computers in order for the line filters and surge suppressors to be most effective. * High-end entertainment gear if it uses 3 prong plugs for similar reasons. * Microwave ovens. For safety, these really should be on a grounded circuit. (A GFCI will not protect against a fault on the high voltage side of a microwave oven, though this sort of fault is extremely unlikely). * Large appliances including refrigerators, clothes washers and dryers, dehumidifiers, window air conditioners, etc. In most cases, there will only be a few circuits where this is needed and only these need to be upgraded. To what extent the wiring plan of your residence separates lighting type circuits from those with outlets that will be used for 3 wire equipment will determine how easy it is to upgrade only those outlets that are affected. It may be cheaper to just add new branch circuits for specific equipment needs.
The question often arises: "Why can't I just connect the H to the N if my
outlets are only two prong?"
For one reason, consider the 'appliance' below:
+-----------------+
| | Open Fault
Hot o---------o-o----/\/\---------+------ X -----o Neutral
| Switch Load | |
| (On) |----+ Case should be G but is connected to N
+-----------------+
With the appliance 'on', current passes through the internal wiring/motor/etc.
of the appliance to the N but this is now connected to the case as well. If
the house wiring opens (or even if the plug is loose, it is possible to have
line voltage on the case.
The built-in tester is designed to actually introduce a small leakage current so its results should be valid. Therefore, testing a single GFCI outlet with an external widget is not really necessary except for peace-of-mind. However, such a device does come in handy for identifying and testing outlets on the same circuit that may be downstream of the GFCI. An external tester is easy to construct - a 15 K ohm resistor between H and G will provide a 7 mA current. Wire it into a 3 prong plug and label it "GFCI Tester - 7 mA". The GFCI should trip as soon as you plug the tester into a protected outlet. On a GFCI equipped for grounded neutral detection (as most are), shorting the N and G conductors together downstream of the GFCI should also cause it to trip. Note that such a tester will only work for GFCI protected outlets that are on grounded (3 wire) circuits (unless you add an external ground connection). Thus, just using a commercial tester may falsely indicate that the GFCI is bad when in fact it is simply on an ungrounded outlet (which is allowed by Code in a retrofit situation). The test button will work whether or not the circuit includes a safety ground because it passes an additional current through the sense coil between Hot and Neutral tapped off the wiring at the line side of the GFCI and therefore doesn't depend on having a safety Ground. I suppose you can purchase suitable low cost testers as well (but they are subject to the same must-be-grounded restrictions). Try your local home center or electrical supply distributor.
(From: John Grau (affordspam@execpc.com)). I personally would not feed a subpanel with a GFI breaker. Here are just a few of the reasons: 1. GFI breakers for personnel protection are set to trip at 5 mA (1/1000ths of an Amp). The longer the circuit conductors, the greater the potential for leakage. If you subfeed a panel, you would have the cumulative distances of all circuits connected to that panel to contend with and hope that the breaker would hold. 2. You would not be able to connect any thing to that subpanel that would be a critical load. e.g. freezer, sump pump, well pump, furnace, etc. An unnoticed nuisance trip, could mean that you would come home to a thawed freezer, frozen pipes, flooded basement, etc. 3. Using breakers to achieve GFI protection has 2 downsides: expense, and usually, an inconvenient location to reset the tripped device. A GFI outlet at the point of usage, is usually more convenient to reset, should it trip. Here in Wisconsin, I can buy about 6 GFI outlets for the cost of 1 breaker. There is no compulsory language in the National Electrical Code the forces an update to current code standards, unless you repair, replace or update the affected component. Not all changes in the 1996 code made sense, and I would not update the wiring in my own home (built in 1995) to current standards.
When making measurements on household wiring, one expects to see one of three voltages: 0, 115 VAC, or 230 VAC (or very similar). However, using a typical multimeter (VOM or DMM) may result in readings that don't make sense. For example, 2 VAC between Neutral and safety Ground or 40 VAC between a Hot wire (with its breaker off) and Neutral or safety Ground. The most likely reason for these strange readings is that there is E/M (electromagnetic) coupling - capacitive and/or inductive - between wires which run near one another - as inside a Romex(tm) cable. Where one end of a wire is not connected to anything - floating, the wire acts as an antenna and picks up a signal from any adjacent wires which are energized with their 60 (or 50) Hz AC field. There is very little power in these phantom signals but due to the very high input resistance/impedance of your VOM or DMM, it is picked up as a voltage which may approach the line voltage in some cases. Another possibility is that the you didn't actually walk all the way down to the basement to shut off power completely and the circuit is connected to a high tech switch (such as one with a timer or an automatic dimming or off feature) or a switch with a neon light built in. There will be some leakage through such a switch even if it is supposed to be off - kill power completely and test again. Putting any sort of load between the wires in question will eliminate the voltage if the cause is E/M coupling. A small light bulb with test probes can be used to confirm this both by serving as a visual indication of significant voltage (enough to light the bulb, if weakly) and to short out the phantom voltage for testing with the multimeter. There can be other causes of such unexpected voltage readings including incorrect or defective wiring, short circuits in the wiring or an appliance, and voltage drops due to high current in a circuit. However, the E/M coupling explanation is often overlooked when using a multimeter.
Connect a wire between one prong of a neon outlet tester and a known ground - cold water pipe if copper throughout, heating system radiator, ground rod, etc. (Experienced electricians would just hold onto the other prong of the tester rather than actually grounding it. Their body capacitance would provide enough of a return path for the Hot to cause the neon to glow dimly but you didn't hear this from me :-). Yes, they survive without damage and don't even feel anything because the current is a small fraction of a mA. DON'T try this unless you are absolutely sure you know what you are doing!) With one prong grounded, try the other prong in the suspect outlet: * The Hot should glow brightly and the Neutral should not light at all. This is the normal situation. * If neither side glows, the fuse is blown, the circuit breaker is tripped, this is a switched outlet and the switch is off, or there is a wiring problem elsewhere - or your ground isn't really ground. * If both sides glow and using the tester between the slots results in no glow, then you have an open Neutral and something else on the circuit that is on is allowing enough current to flow to light the neon tester. * If both sides glow and using the tester between the slots results in an even brighter glow, the outlet is wired for 220 V, a dangerous violation of the NEC Code unless it is actually a 220 V approved outlet. It is unlikely you will ever see this but who knows what bozos worked on your wiring in the past!
So your $6 outlet tester displays a combination of lights that doesn't make sense or one or more lights is dim. For example, all three lights are on but K and X (see below) are dim. The three neon bulbs are just between what should be (The first letter is how the light is marked on mine): K Hot to Ground (GROUND OK). O Hot to Neutral (HOT OK?). X Neutral to Ground (HOT/NEUTRAL REVERSE - should not light). I suspect at the very least that your ground is not connected at the service panel. I may run from some/all the outlets but ends somewhere. You are seeing capacitive/inductive pickup between the floating ground and the other wires in the circuit. Your N and H may be reversed as well but this cannot be determined without checking with a load between H/N and a proper ground. I would recommend: 1. Determining if the ground wire for those 3 prong outlets does indeed go anywhere. 2. Determining if the Hot and Neutral polarity is correct by testing between each of the prongs and a confirmed ground (properly connected 3 prong outlet, service panel, or a cold water pipe in an all metal water system) with a load like a 25 W light bulb. The neon lamps in the tester or a high impedance multimeter can be fooled by capacitance and other leakage paths. For a computer or other 3 wire appliance, you should really install a proper 3 prong outlet wired correctly. Otherwise, any power line filters and surge suppressors will not have the safety ground (which a GFCI does NOT create). Some UPSs may get away without one but then their surge suppressor and/or line filters will not work correctly. Some appliances like microwave ovens MUST have a proper safety ground connection for safety. This not only protects you from power line shorts to the case but also a fault which could make the case live from the high voltage of the microwave generator.
"I have a 220 outlet that I need to plug an AC unit into. The AC unit works fine in another outlet, but not in this specific outlet. I pulled out my handy dandy meter and checked the voltage across the two line slots - the meter read 0. But when I tried one line and the ground I got 125 V. Similarly, when I tried the other line and the ground I also got 125 V. What's the scoop? Why does the meter, and obviously the AC, think that there isn't 220 V coming in? Any help is greatly appreciated - as this room is stinking hot right now!" Did it ever work? It sounds like both slots are being fed from the same phase of the power from the service panel. Check with a load like a 100 W light bulb between each slot and ground. This could have happened during the original installation or during renovation. Another possibility is that there is some other 220 V appliance on the same line with its power switch in the ON position (and not working either) AND one side of the line has a tripped breaker or blown fuse. Yet another possibility: (From: David L. Kosenko (davek@informix.com)). My load center is GE unit. They make both full height and half height breakers. If you use a half height breaker set for a 220 line, you must be careful to install it across the two phases. It is very easy (especially if you don't know about 220) to place the ganged breakers into a single full height slot in the load center, giving you both lines off the same phase line.
This may trip the breaker or blow a fuse - or trip a GFCI if so protected. The procedure below is specifically for GFCI tripping. You will need a multimeter. * First, unplug everything from the circuit and see if it still trips. If it now does not trip, one of the appliances was the problem. Try them one at a time to see which is the problem and then check the section for that or a similar appliance elsewhere in this document. Assuming the circuit is at fault: * You need to determine whether this is a H-G leakage fault (which is what most people think is the only thing GFCIs test for) or a shorted G-N fault. * A H-G fault that doesn't trip the normal breaker might be due to damp wiring (an outside outlet box that gets wet or similar) or rodent damage. * A shorted G-N fault means that G and N are connected somewhere downstream of the GFCI - probably due to incorrect wiring practices or an actual short circuit due to frayed wiring or wires touching - damage during installation or renovation. Assuming the line is separate from any other wiring: * With the line disconnected from the service panel (all three wires), first test between each pair of wires with the multimeter on AC to make sure it is truly dead - there should be virtually no voltage. H-G, N-G, and H-N should all be close to 0 (say, less than a volt). * If this passes, test across the dead line's H and G for leakage on the resistance range. It should be greater than 15 K ohms (it should really be infinity but to trip the GFCI requires around 15 K ohms or less). * Then, test for resistance between H and G - this too should be infinity. One of these will show a fault - possibly the N-G test indicating a short or improperly wired outlet since this would not result in any operational problems until a GFCI is installed (though it does represent a safety hazard).Go to [Next] segment
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