Thermostat wire for doorbell? 18-2 or 18-5?


Old 11-23-13, 07:11 PM
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Thermostat wire for doorbell? 18-2 or 18-5?

I was browsing thermostat wires at my Hardware store, and found that the packaging on both the 18-2 and 18-5 thermostat wire had some words showing that the thermostat wires were good for doorbell and security wiring also.

My question is... Which wire should I go with 18-2 or 18-5? I'm not really sure if I understand why someone would choose an 18-5 wire, but there must be a reason.
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Old 11-23-13, 08:00 PM
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Sometimes wires fail. With 18-5 you just abandon the failed wire and use a different one. With 18-2 you either have to find where it failed or replace the whole cable.
Old 11-23-13, 08:27 PM
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Probably 99% of the chimes out there can be wired with 18-2 thermostat cable. If you have a chime that plays a tune, meaning it has a programmable chime in the chime unit, you'll need a 3rd wire to the transformer to allow the chime unit to operate after the momentary push of the button. You never need more than 18-2 thermostat cable to run to a pushbutton.
Old 11-24-13, 12:47 PM
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As Ray said, the 18-5 would be a safe choice as it gives you extra wires in the event one of them craps out. Ex: "I'm putting up a new picture (bangs nail in wall). Oh crap my doorbell stopped working! (nail hit doorbell wire, severing black). Thats ok, I have 3 extra wires to replace the black with, man I'm smart for using 18-5!"

And generally, any wire smaller than 14 AWG is used for extra low voltage applications. 18 AWG I have used for thermostats, security, doorbells, and fire alarm initiating loops.
There are LED lights coming out that will run off of Cat5 cable which is 23 AWG.
And your curiosity about the 18-5...
The cable you are looking at is, as I said before, suitable for different applications. The 5 conductor is for thermostat applications which require 5 wires.
Old 11-24-13, 08:08 PM
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Hey. You guys are great. Thanks for the advice. I'm going with some 18-5 wire since I also have to wire my thermostat too. Thanks again.

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