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Hi see the attached pic. The one on the right is for the fan. There is no ground screw, but I can see a wire was left behind the switches (connected to nothing, I think that's the ground.) check the voltage acroos the two screws on the right side of the switches. There showed different results. The right switches always read 120V when I flip up and down. But the left switch changes with the position of the flipper. I guess the right switch (for the fan) is bad. I also checked the power to the fan inside the fan opening on the ceiling, no power at all. Do you think I'm correct? Can you tell me where to get the replacement switch?
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I was trying to the expert who helped yesterday, but somehow ended up with you. But it is absolutely fine.
Anyway, the fan is not working.
are you still there?
Hi the ground wire by code at one time was not required and often left off of light switches. The function is not dependant on the ground and unless you are tripping breakers should be left as is. I am a little perplexed at the switch that reads 110V across the two screws as to get a proper reading the probes should be on a energized wire and a grounded wire which does not terminate on switches. Only the energized wire and the wire to be energized are. Which is why you got irratic readings on the other switch. Check the wire make up in the switch there will be a three incoming wire cables or romex cable. One black wire is constantly hot from the source and needs to be tested to ground with all switches off. This wire splices and terminates at the top of both of the switches to supply power. The black wires from the two remaining cables that read 0 to ground terminate one to each bottom screw. The white wires all get spliced together supplying a ground path for the unbalanced load. The same for the green/bare wires both splices pushed to the back of the box. If you purchase switches with ground screws as replacements you are required to add two additional bare wires from the splice for each screw. Again no baring on the function. Test each colored wire to the bare wires for an accurate reading and I will look for your response.
sorry did not see your post good evening.
There might be a fourth wire if the power is extended to another room or device. It should be spliced identicle with the incoming power cable.
The left switch controls the lights, the right one goes to the fan which is the problem. The switches look identical, but why they showed a different test results?
The right switch controls a motor to which the hot and ground alternate and read identically. The alternating current is what spins the motor.
The fan switch does not respond to the position of the flipper, and always appear 120V.
Each black wire tested to ground will show two energized wires one on each off switch,
It had been working until a few days ago. I don't think there are wiring issues.
Is there a receptacle in the fan housing? check voltage there please.
With the switch on.
Yes, I did, seems no power even with the fan switch turned on.
Many time the motor assembly plugs into the housing to addapt to different motors.
not sure what you mean, could you elaborate?
You are getting 110V with one test lead touching the bare wires and one touching each black? Or each lead on a black?
Could you read my initial question please.
You need to identify the incoming power and the switch leg going to the motor. To get a proper voltage reading your test probes need to touch a black wire and the other a bare wire. Here you will get one wire reading voltage and the other does not if the switch is off.
My point is, it shouldn't have worked ever if the wiring is wrong. But this is not the case. It worked for a long time until a few days ago.
No additional work or remodel? Then replacing the switch is definitely in line. I was under the impression aswering why the reading were different that it was a new or remodel and the wire make up was wrong. Replace the switch with a motor rated switch for a longer life.
It should fire right back up
Turn the power off at the circuit panel first please.
where to get the switch?
By reading across the two black wires you created a bridge to read to ground. It does not mean the switch is closed properly
Any hardware store will carry them.
I could not even see the color of the wires, I only put one probe on each of the two screws on the right side of the switches.
There was not current flowing through the switch.
Do you think the two switches function differently?
To me they look exactly the same.
Is why you read nothing passed it, by bridging it with a tester it reads incoming and ground.
No the fact they have on off on the toggle indicates they are single pole switches nothing more.
Unfortunately they are residential lighting switches not meant for the brunt start up load of a motor.
Mike, thank you. But could you release the question to other experts, I'd like to hear a bit more to clear out some confusion.
You will see the motor rated switch to be larger in construction.
Absolutely you have a good evening.
If you require anything else I will be on tonight.
Please release the question, so others can take it. Thanks.
Did it go back to the board?
I don't think so.
errr sorry let me try once more.
You did not release!
I'm getting a bit unhappy.