First let me make it clear I am talking about very mild “tingles” and not proper electric shocks. If anyone receives an electric shock, the appliance should be disconnected immediately and an appliance engineer called out. Mild electric shocks or tingles might not be taken seriously, but they can turn into lethal full mains voltage shocks at any time.
So never use any appliance even if you only get a mild shock from. Disconnect it immediately. The reason you get shocks from a washing machine, or any other appliance, is because it is not earthed properly.
Why Does an unearthed appliance cause shocks?
All large appliances need to be connected to earth for safety. The earth wire runs down the mains cable and then through the socket it is plugged into. If this connection becomes broken at any point in the machine, cable, plug or wall socket, then you can get the symptom of mild electric shocks.
The shocks are often mild, or just tingles because they are caused by small amounts of electricity leaking or inducing across to the disconnected earth wire and running through the casing. It's a phenomenon related to eddy current, but it's not necessary to understand the scientific reason. The effect is useful to us though because without it we would be unaware the earth is not connected unless conditions later allow a full electric shock, which could be fatal.
Such an appliance poses a serious danger. Because the mild shocks indicate that the washing machine is not earthed it means that if a component inside the machine's insulation breaks down, or a live wire comes adrift and touches the metal parts inside, then the low voltage current will be replaced by the full mains voltage – which can kill. Without a path to earth, the washing machine cannot blow the fuse, and instead could just work as normal but be lethal.
Plug not earthed?
The first thing an engineer is likely to check is the appliances plug. They would check inside the plug to make sure the green and yellow earth wire is connected securely.
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If it’s OK, then either the earth wire inside the mains cable could have a break somewhere inside and needs replacing, or it may not be connected inside the washing machine. (The latter is very unlikely, I’ve never known it, but it’s theoretically possible). Both can (and should) be checked with a continuity test meter by checking the continuity between the earth pin on the plug and the metal door hinge or another suitable bare metal point on the washing machine.
Moulded plugs
Most appliances have long since come with pre-fitted moulded plugs which can’t be checked. So if unable to check inside the plug the first thing an engineer would check is the continuity down from the earth pin as described above. If he had a good reading he shouldn’t need to look inside the plug anyway. If the reading was open circuit or high resistance, but the earth was connected properly inside the machine he’d cut off the plug about an inch down and replace it because earth wires can break at that point. If that failed to make a difference he’d replace the mains cable.
Extension cables
If the appliance is plugged into an extension cable then clearly there could be a problem anywhere on the extension. So an engineer would check the earth connections and continuity on the extension cable. Ideally ditch the extensions, they aren’t ideal on large white goods appliances. If one is necessary try another extension (but make sure it’s appropriate – appliances and extension cables). I have seen appliances plugged into totally inappropriate extension cables that are using 2 core cable with no earth!
Wall socket not earthed
Another possibility is a fault in the wall socket. The earth wire could be disconnected inside or the brass earth prongs inside could be worn or too far apart to grip the earth pin on the plug properly. Obviously you don’t mess with wall sockets. If you suspect a faulty wall socket get an electrician – not an appliance engineer.
Don’t confuse with static electricity discharges
If you get just a single short shock when you touch an appliance (possibly accompanied by a cracking sound) which doesn’t reoccur when you touch the appliance again this could be static electricity discharging from your body and is very different to this issue.
Stewart harrod says
Hello there
My cooker at home occasionally gives me an electric shock I have some electrical knowledge and testing equipment I am aware the cooker is on its own circuit
I just want to clarify if I test between the cooker outlet earth pin and the metal cooker I should hear my testers beep to show continuity ? This would show my cooker is properly earthed ?
Many thanks fur your time
Andy Trigg (Whitegoodshelp) says
Hello Stewart. I would test for good continuity between the earth in the cooker socket and anything bare metal on the cooker (not painted parts of course) and the actual metal elements if it has the old style metal elements. But getting a good earth there only tests the cooker and its cable so if you find no fault you’d have to investigate if the cooker socket earth is actually earthed somewhere.
a jones says
all my white goods in the kitchen give me intermittent small electric shocks, how do i create a better earth connection in the kitchen
Andy Trigg (Whitegoodshelp) says
If your sockets aren’t earthed I would expect them to give you small electric shocks every time you touch them unless by any chance it is dependent upon what shoes you might be wearing. Unless by any chance you are generating static electricity and earthing to the appliances it sounds like you need an electrician to check all your sockets ASAP.
A Simon says
Hi Andy,
I’m out in the Middle East and not a single socket is earthed.
I was getting shocks from my oven and an electrician came out and earthed it by drilling a hole in the floor and running a wire from the back of the oven to the hole in the floor and it did the trick.
I bought a blender the other day and I am getting the same shocks. My question is, how can I earth my blender? Would it be possible to run a wire somehow from the blender into the same wire from the oven?
Andy Trigg (Whitegoodshelp) says
It sounds like the electrician needs to earth all of the sockets. I don’t know what voltage is used over there but if it’s potentially lethal you should not use any appliance with metal parts that can be touched if it is not earthed. As my article explains, the relatively mild shocks you can receive when an appliance is not earthed can turn into fatal shocks if one of the appliances goes faulty inside and allows mains voltage to run through to earth. When plugged into a socket with all earth connections intact such an incident would instantly blow the fuses but if there is no earth then the appliance will continue to function but could potentially kill.
I don’t know how common it is over there, it’s hard to imagine any circumstances where someone would install electrical sockets without any earth.
Miles says
I recently bought a new washing machine and paid an additional £25 for it to be installed. The cable had to be hard-wired to the connection box in the wall, just as the previous washing machine had been. (There is a switch with a fuse on the wall above the worktop.)
The new washing machine worked well but after one wash, when the machine was switched off and I was unloading the washing with one hand, I rested my other hand on a metal draining board, and received an electric shock from the washing machine drum. I used a multimeter to test the voltage between the metal drum and the metal draining board, and found it was 123 volts AC. I assume the metal draining board is connected to the earth through the copper water pipes.
As I thought there was a fault with the washing machine, I contacted John Lewis Technical Support by e-mail. They phoned me and e-mailed me very quickly, and were very helpful. They gave me the link to this web page.
When I checked the connections in the connection box, I found the three wires were firmly screwed into the correct terminals. The insulated earth wire was lying across the brass screw holding the blue wire from the mains supply cable. I assume that a current was being induced in the earth wire at or near this location. I disconnected the washing machine cable and reconnected it with a slightly longer insulated earth wire so that it did not rest on the screw.
I used the multimeter to test the voltage between the metal drum and the metal draining board, and found it was now zero. I also touched the metal drum with one hand and the metal draining board with the other hand, and did not receive an electric shock.
[I took photos of the wiring in the connection box before and after I reconnected the cable from the new washing machine. I would be happy to e-mail them to you, if you would like to add them to this web page.]
Andy Trigg (Whitegoodshelp) says
Hello Miles. Yes please, use my contact form to get in touch and you can then reply to my response email attaching photos. I can’t quite make sense of your experience as I’m not aware that voltage could be induced simply by a wire resting on top of a neutral terminal. I would also expect that if 123 volts was somehow induced into the earth wire it should trip the electrics immediately.
The only cause I know that can allow voltage to run through the earth on an appliance is induced from the insulated live wire it runs next to within the mains cable if the earth wire is not connected to earth.
Oriana says
Hello,
I live in a shared house with three other people and already for a long time we’ve all been feeling tiny electric shocks when we use the water from the bathroom (but not the shower). We think it could be connected with the washing machine, because it happens a lot more when it is on.
We also thought it could be the water boiler, but it doesn’t happen in the shower.
What we find strange is that the tap (metal) is not charged, it is only the water (and it is not static electricity because it can happen several times while, for example, you wash your teeth).
How can something like this happen? Should we call a general electrician or a washing machine tech? (we have no experience on fixing appliances so we’re kind of scared to touch too much)
Thank you very much, best regards
Oriana
Andy Trigg (Whitegoodshelp) says
Oriana, is the washing machine in the bathroom? I’ve never heard of anything like you describe, but if any electricity was somehow in the water it’s impossible for it not to get to the metal tap so it’s very strange. I would get a good electrician in asap.