Behind the Drywall Splices

Reply

  #1  
Old 07-04-13, 06:48 PM
Member
Thread Starter
Join Date: Jul 2013
Location: USA
Posts: 4
Received 0 Votes on 0 Posts
Behind the Drywall Splices

I have a 160+ yr old home. I have several overhead lights/fans that have 2 lead cloth wire in the box, but when you open the switch, it has 2 lead vinyl wire using the white and black across the switch. This leads me to the conclusion that there is a splice behind the drywall. How do I find the splice? In other areas I have found open splices behind the drywall & it concerns me.
 
Sponsored Links
  #2  
Old 07-04-13, 08:20 PM
pcboss's Avatar
Forum Topic Moderator
Join Date: Jul 2002
Location: Maryland
Posts: 14,944
Received 30 Votes on 26 Posts
Can you look above the ceiling? Are old work boxes being used?
 
  #3  
Old 07-04-13, 10:38 PM
Nashkat1's Avatar
Member
Join Date: Mar 2012
Location: USA
Posts: 8,470
Received 1 Vote on 1 Post
I have several overhead lights/fans that have 2 lead cloth wire in the box, but when you open the switch, it has 2 lead vinyl wire using the white and black across the switch.
The switch is wired with a switch loop. The other end of the cable from the switch should meet the house wiring for the lights in a ceiling box.

You mention several overhead lights and fans and only one switch. Does one switch control all of the lights and fans you're looking at on this circuit?
 
  #4  
Old 07-05-13, 07:49 AM
Member
Thread Starter
Join Date: Jul 2013
Location: USA
Posts: 4
Received 0 Votes on 0 Posts
Both of these boxes are between the 1st and 2nd floor. One of the ceiling fans has one 2 lead cloth wire going into the box and a 2 lead vinyl going into the switch so the power has to be coming from somewhere behind the drywall. I have taken apart all the nearby outlets and switches to see if they used one of those to relay the power but no luck. The other has three 2 lead cloth wires coming into the overhead box but only one 2 lead vinyl in the switch.
 
  #5  
Old 07-05-13, 08:40 PM
Nashkat1's Avatar
Member
Join Date: Mar 2012
Location: USA
Posts: 8,470
Received 1 Vote on 1 Post
One of the ceiling fans has one 2 lead cloth wire going into the box and a 2 lead vinyl going into the switch so the power has to be coming from somewhere behind the drywall.
This should be a switch loop setup. If so, the older cable with the woven sheath should be carrying 120V, unswitched, from the panel. You can use an analog multimeter set on 200 or 250VAC to verify this by disconnecting the wires, turning the breaker on, and testing across the black and white wires in that cable.

If the two wires in the older cable do have 120V available, turn the breaker off, tag the white wire in the newer cable with black or red electrical tape or permanent marker, to show that it is carrying ungrounded power, and splice that wire to the black wire in the older cable. Attach the ground wires from your fan/light combo to the green ground screw in the metal fan-rated box. Splice the white wire from the fan to the white wire from the panel.

If you're going to control this fan/light combo with a 2-wire fan/light wall control, splice the power feed wires for the fan motor and the light to the black wire from the switch. If you want to control just the light from a wall switch, add the power feed for the fan motor to the splice of the black panel wire and the tagged switch wire, and splice the power feed for the light to the black switch wire.

At the switch, tag the white wire to show that it is carrying ungrounded power.

The other has three 2 lead cloth wires coming into the overhead box but only one 2 lead vinyl in the switch.
The three older cables should be a feed from the panel, a feed out to another load, and a switch loop. The switch loop is spliced, in a box somewhere, to newer wiring.

Disconnect and separate all of the wires in your fan-rated ceiling box. Turn the circuit on at the breaker and test each pair of wires to see which cable is feeding the power in. Turn the power off and tag that cable. Remove the switch from the wall and disconnect the black and white wires connected to it. Straighten the wires and use a wire nut to join them together temporarily. Set your multimeter to continuity or ohms. Test the wires in the other two cables to see which gives you a reading. Mark that cable as the switch loop.

Tag the white wire in the switch loop cable to show that it is carrying ungrounded power and splice it to the black wires in the other two cables. Attach your ground wires as before. Splice the white wire from your fan/light combo to the two white wires in the two non-switch cables. Make up the power feeds for the fan motor following the instructions above, depending on which way you want to control them.

Tag the white wire at the switch.
 
Reply

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Thread Tools
Search this Thread
Display Modes
 
Ask a Question
Question Title:
Description:
Your question will be posted in: