Steve and I installed two Nest Protect smoke and carbon monoxide alarm from nest.com, and thought you might enjoy a visual guide to how it’s done.
NOTE: Do NOT try this if you’re not already comfortable with identifying the correct circuit breaker and how to ensure that you won’t get electrocuted! If you’re not comfortable with this – hire a professional or ask your mom to help you!
01 Revealed wires from old smoke detector
![01 Revealed wires from old smoke detector](http://media.screensteps.me/nosillacast/fvz9vn/01-revealed-wires-from-old-smoke-detector.png?1386105817)
02 New wiring harness
![02 New wiring harness](http://media.screensteps.me/nosillacast/fvz9vn/02-new-wiring-harness.png?1386105821)
03 Steve setting up voltmeter (safety first)
![03 Steve setting up voltmeter (safety first)](http://media.screensteps.me/nosillacast/fvz9vn/03-steve-setting-up-voltmeter--safety-first-.png?1386105822)
04 Voltmeter connected to house wiring
![04 Voltmeter connected to house wiring](http://media.screensteps.me/nosillacast/fvz9vn/04-voltmeter-connected-to-house-wiring.png?1386105824)
05 Steve monitoring voltmeter
![05 Steve monitoring voltmeter](http://media.screensteps.me/nosillacast/fvz9vn/05-steve-monitoring-voltmeter.png?1386105826)
06 Turning off the circuit breaker
![06 Turning off the circuit breaker](http://media.screensteps.me/nosillacast/fvz9vn/06-turning-off-the-circuit-breaker.png?1386105829)
07 Confirmation electricity is not flowing
![07 Confirmation electricity is not flowing](http://media.screensteps.me/nosillacast/fvz9vn/07-confirmation-electricity-is-not-flowing.png?1386105831)
08 Stripped portion of the cable wos originally too short
![08 Stripped portion of the cable wos originally too short](http://media.screensteps.me/nosillacast/fvz9vn/08-stripped-portion-of-the-cable-wos-originally-too-short.png?1386105834)
09 Connecting new cable harness with wire nuts
![09 Connecting new cable harness with wire nuts](http://media.screensteps.me/nosillacast/fvz9vn/09-connecting-new-cable-harness-with-wire-nuts.png?1386105837)
10 Buzzy monitoring the operation
![10 Buzzy monitoring the operation](http://media.screensteps.me/nosillacast/fvz9vn/10-buzzy-monitoring-the-operation.png?1386105840)
11 New wire harness in place
![11 New wire harness in place](http://media.screensteps.me/nosillacast/fvz9vn/11-new-wire-harness-in-place.png?1386105855)
12 New faceplate
![12 New faceplate](http://media.screensteps.me/nosillacast/fvz9vn/12-new-faceplate.png?1386105857)
13 Supplied mounting screws excessively long so we used original screws
![13 Supplied mounting screws excessively long so we used original screws](http://media.screensteps.me/nosillacast/fvz9vn/13-supplied-mounting-screws-excessively-long-so-we-used-original-screws.png?1386105859)
14 Electric drill to start the original mounting screws bayonet side down
![14 Electric drill to start the original mounting screws bayonet side down](http://media.screensteps.me/nosillacast/fvz9vn/14-electric-drill-to-start-the-original-mounting-screws-bayonet-side-down.png?1386105860)
15 Switched to manual screwdriver as plate was very thin
![15 Switched to manual screwdriver as plate was very thin](http://media.screensteps.me/nosillacast/fvz9vn/15-switched-to-manual-screwdriver-as-plate-was-very-thin.png?1386105862)
16 Underside of nest showing bayonet mounting holes and connector port
![16 Underside of nest showing bayonet mounting holes and connector port](http://media.screensteps.me/nosillacast/fvz9vn/16-underside-of-nest-showing-bayonet-mounting-holes-and-connector-port.png?1386105863)
17 Nest bayonet mounting holes visible and connector attached
![17 Nest bayonet mounting holes visible and connector attached](http://media.screensteps.me/nosillacast/fvz9vn/17-nest-bayonet-mounting-holes-visible-and-connector-attached.png?1386105865)
18 Constantly bumping the button caused the Nest to keep trying to test
![18 Constantly bumping the button caused the Nest to keep trying to test](http://media.screensteps.me/nosillacast/fvz9vn/18-constantly-bumping-the-button-caused-the-nest-to-keep-trying-to-test.png?1386105866)
19 Blue light after successful test
![19 Blue light after successful test](http://media.screensteps.me/nosillacast/fvz9vn/19-blue-light-after-successful-test.png?1386105869)