Ceiling fan installation from hell

soupcxan

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I am not an electrician but I have replaced ceiling fans before and never had a problem, until today.

I am replacing a ceiling fan/light on the 2nd floor in my 1965 house. The old fan/light appeared to be original and it had a strange fan speed control box mounted on the wall that had what looked like a transformer block wired to the speed knob. There was no wall switch for the light, you had to use the pull cord.

My plan was to install a new fan/light, install a wall on/off switch where the speed control used to be, and put both the fan and lights on one circuit (so the wall switch could turn the entire system off, not just the fan).

I bought a new Hunter ceiling fan/light (~$100) and installed it. It came with a wireless remote for speed/light but I didn't want that so didn't wire it in. I directly connected the black house wire (hot) to the black fan wire and the striped light wire, and then connected the white fan wire to the white house wire.

I turned the breaker on and went back to the fan. The fan works. The lights work. Literally a minute after I turned it on, one of the 14W CFLs that came with the fan pops and goes dead. 2 minutes later, another one pops. I figure they were cheap and maybe got banged around in transit so got some other CFLs from other fans in my house and put them in. Within 5 minutes 3 more CFLs popped and went dead.

I thought maybe the fan needed the remote control box installed between the house power and the fan/lights, so I wired it in per the instructions. When I turned the power on, the remote control box popped and the side where the wires is turned black. Nothing on the fan works. Time to reassess.

Clearly something is very wrong here. I have multiple other (newer) ceiling fan/lights in my house and they work fine. Some have CFLs, others have incandescents. Could this particular line be wired for more than 120V? Is there a reason the fan and lights need to be on a separate circuit (I think they're all 10A)? I don't have a multimeter but need to get one. I already threw the old fan and speed control away so can't check them for details.
 
You can get a multimeter at Home Depot for under $20. Where is the ground wire in the light wiring? Or is the house so old it has no common grounds? The white wire should be neutral.

In some of the old houses I have worked on, the ground wires were attached to the metal fixture boxes and not the devices (plugs, etc).
 
Funnystory, may be relevant to OP's problem. I recall years ago a Vietnamese family having problems keeping light bulbs in a hallway fan/light fixture. The bulb burned out and they replaced it. As soon as the switch was flipped on, the bulb blew. After several bulbs wewre trashed they decided help was needed.

A friend who employed the couple at her house asked me to see if I could remedy the problem. Finding my way into the seedier parts of Philadelphia, found their home.

A quick check with a voltmeter identified the problem. The fan and light socket were wired for 220 VAC. I told papasan to go to a commercial electrical house and get a 220 volt bult. His English was poorer than my Vietnamese. I wrote a note for what he needed, and after some haggling at the electrical shop they finally sold him a 220 volt bulb.

All was well thereafter...
 
Agreed on the meter. On any wiring that you aren't 100% certain of (and since you ripped out old wiring, this qualifies as 'uncertain') you want to check that:

Hot-Neutral = 120V
Neutral-Ground = 0V
Hot-Ground = 120V

It is good to double check all of that with wires attached to a standard incandescent light bulb. These will load the circuit, where as the meter is high impedance and just senses the voltage w/o loading it like the actual appliance will.

-ERD50
 
Lighting circuits can be tricky, especially in older homes where it was common to have the hot feed go directly to the fixtures on the circuit, each fixture then controlled by a drop to the switch. If the drop to the switch is romex or BX cable, they use the white. In this case, many times the "white" wire on the switch leg means nothing since it just interrupts the hot. So, you have to be careful. When this is done, it is supposed to be marked with tape or black marker, but that frequently fades, falls off, or was never done. Let me reiterate. In this kind of circuit, the white is hot. Yes it is. Be careful.

This is a nice little simple reference of two simple wiring methods for lighting: Wiring a Light Switch : Electrical Online

I always have my testers ready. First my simple "bug light", and then the DVM. It would be really unusual to have 240 to a light switch, although this could theoretically happen if for some reason two different hot circuits of the split phase power came into the box. Yikes! But, hey, anything is possible in a 1965 house, especially if there have been a lot of cooks in the wiring through the years.
 
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Hot-Neutral = 120V
Neutral-Ground = 0V
Hot-Ground = 120V

Here is what I can confirm using the highly scientific "does it zap my finger" test:

Wall switch OFF (this is a new switch so know it works)
Hot-Neutral = ok.
Neutral-Ground = ok.
Hot-Ground = Ow!

Wall switch ON
Hot-Neutral = Double-OW!
Neutral-Ground = ok.
Hot-Ground = OW!

I can't precisely estimate the voltage until Amazon delivers my multimeter, but I would say the pain feels worse between the hot-neutral with the wall switch on...[puts flame suit on]...

Oh, and I found a picture of the old fan's voltage regulator (a similar one anyway).
 

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... It would be really unusual to have 240 to a light switch, although this could theoretically happen if for some reason two different hot circuits of the split phase power came into the box. Yikes! But, hey, anything is possible in a 1965 house, especially if there have been a lot of cooks in the wiring through the years.

That is exactly what I suspect - two hots. Like you said, if they used a white as a hot, and that is on the other phase from the black, you'd have 220V.

-ERD50
 
I ran into that issue when I was doing residential A/C service work for a national retailer. Customer buys a 5,000 btu 120v A/C, plugs it in. Runs five minutes and fan quits. I came out on the warranty call, fan motor is open, I replace it. Runs for five minutes, then quits. Hmmm.

Having noticed that there wasn't the usual difference in fan speeds (hi, med, low) the light in my head goes on and I check the wall outlet voltage. Yup, 220V. Told customer to call an electrician, and oh, the next fan motor is not covered under warranty and I cannot promise that the compressor is not damaged.

No one back at the shop had ever heard of that happening. Now I guess I know.
 
I ran into that issue when I was doing residential A/C service work for a national retailer. Customer buys a 5,000 btu 120v A/C, plugs it in. Runs five minutes and fan quits. I came out on the warranty call, fan motor is open, I replace it. Runs for five minutes, then quits. Hmmm.

Having noticed that there wasn't the usual difference in fan speeds (hi, med, low) the light in my head goes on and I check the wall outlet voltage. Yup, 220V. Told customer to call an electrician, and oh, the next fan motor is not covered under warranty and I cannot promise that the compressor is not damaged.

No one back at the shop had ever heard of that happening. Now I guess I know.

I once owned an old house where when I went to sell it, the purchaser's inspector noted that an outlet in the dining room was bad (I don't recall what the tester showed). It turned out to be 220V on a 110V outlet. Good thing we never tried to use that one. My theory is that there was once a window air conditioner at that location, and an owner before me didn't want to bring attention to the fact that the AC didn't work so good in that room, so he got rid of the window-rattler and switched out the outlet to camouflage it.

I guess my only point is that you just can't assume previous owners of older houses haven't done just the most stupid things.
 
Wow. This is so incredible to hear about some of these wiring faults. Scary stuff.

A good home inspector will open the panel and check that all circuits are properly connected. It should be easy to see this mischief at the main panel on most romex wired homes.

Some areas of the country still require conduit in the home. If done right, this is the best way to wire. However, you can really create some crazy circuit issues with that flexibility.

I'm still shaking my head over someone swapping out a 110 outlet on a 220 circuit. Wow.
 
Our house is a 70s built ranch style which we bought about 20 years ago. I got a good deal on the house back then. That's because it was mish mashed together like you guys have been noting. I am pretty good at working on stuff, and spent the first couple years redoing everything to make it right, and bring it up to code. Actually, I would be surprised if there was any real building codes in SC back then. I redid the wiring, plumbing, added wall sockets, etc.

Bottom line...I am continually surprised at the way people live and the half-assed way they do things. A lot of ignorance and cheap skates out there. I guess the two go together. I don't know why there are not more house fires.
 
Fluke confirms: 240V hot to neutral. No wonder it hurt so much. Somehow the neutral I picked up from the fan switch must be out of phase with the other hot. But that's a new one on me.
 
Speaking of DVM, I have several high-quality ones, but could not resist picking a cheapo one up at HarborFreight today.

Cost: free with a coupon sent in the mail. Often on sale at random prices from $2.99 to $5.99.
 
Speaking of DVM, I have several high-quality ones, but could not resist picking a cheapo one up at HarborFreight today.

Cost: free with a coupon sent in the mail. Often on sale at random prices from $2.99 to $5.99.
I have a bunch of these. It is convenient to be able to measure voltage and current at multiple places at a time when I'm playing with a circuit. Definitely worth the price (free).
 
A bad common connection will give you different voltages on each leg of the circuit. My garage has 220 volt wiring for a welder, so I added a small breaker box to further break it into two 20 amp circuits for my 110 volt power tools. I made a poor common connection and got some crazy high voltages on one leg until I figured out my mistake. :blush:
 
When I checked the ceiling box, there are 3 sets of wires (I call them pair but they include a copper ground wire) plus 1 extra black wire by itself.

Pair 1 - runs to wall switch, no current
Pair 2 - house power, 120V
Pair 3 - connects to additional outlets in the next bedroom, no current
Extra black wire - 120V to ground or common on the other wires, however also measures 120V to hot from pair 2. When combined with pair 2 this wire gets to 240V which is why my light bulbs were blowing.

I have no idea where this "spare" hot wire is coming from. All the other wires in the house I've seen so far have been romex with white/black/copper. I capped/taped the extra wire and put it back in the box.
 
Those bulbs can not be dimmed ... hence the fan switch blows them.
 
I have a bunch of these. It is convenient to be able to measure voltage and current at multiple places at a time when I'm playing with a circuit. Definitely worth the price (free).
You're my man! It's even worth the $2.99 or the $3.99 or whatever.

However, one would need cords with a banana plug on one end and a clip on the other to set up several meters for instrumentation. These can cost more than the DVM if one does not know where to shop (Well, everything costs more than $0!). Of course, ebay comes to the rescue.

...
When combined with pair 2 this wire gets to 240V which is why my light bulbs were blowing...
As we know, there are 2 hot lines carrying 110-120V into the home. Being out-of-phase, they are 220-240V between themselves, and that's what powers the heavy loads such as water heater, clothe dryer, AC, range/oven, etc...

For the rest, usually the outlets for appliances are powered with one circuit, while the lights are powered with another circuit. This is so that if the missus blows the breaker that powers her hair dryer, it would not also take out the bathroom light fixture and leaves her in the dark raving mad.

So, the two hot lines are both brought into the home, as distributed by the two banks of breakers inside the main panel. However, the circuits from the breakers are separate, and one does not have 220-240V except for the intended loads.

Somehow the guy before you managed to crosswire two different circuits, and to bring both of them up to the fan!
 
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PS. Could it be that the intention was to power the fan with one hot line, and the lights with the other line?

That way, if the fan power is taken out by an overloading plugged-in appliance, you would not be in the dark?
 
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