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How To Install A Wired Smoke Alarm

How To Install A Wired Smoke Alarm

Wondering how to install a wired smoke alarm? We can help with that. Let our years of experience guide you.

Check with your local electrical and building codes before wiring a hardwired smoke detector. You will need to have a continues loop for other smoke detectors to communicate.

How To Install A Wired Smoke Alarm

When wiring a hardwired smoke detector you will need to get a 120 volts power source feed. This power source feed will need to come from a lighting circuit.

The power source feed should be a piece of 14/2 NMD 90. This would feed to the first smoke detector.

The wire would mount into an octagon box on the ceiling. You can also be mounted on the wall within 1 foot of the ceiling.

The wire should be terminated inside of the octagon box. The bare copper should be wrapped around the grounds crew.

This leaves you with a white and black wires to be wire nutted onto the smoke detector wiring harness.

When installing a single smoke detector you will see on the back of the wiring harness that it has three wires a black a white and a red.

This will not be used in this case as it is to talk to other smoke detectors.

You will simply match the colors up from the back of the smoke detector wiring harness to the peace of 14/2 that you have run into the octagon box.

White white and black to black.

You can then install the backing plate from the smoke detector onto the octagon box.

Pay close attention to how it mounts onto the wall there should be arrows facing up. If your mount is on the ceiling then it does not matter.

From that point the wire harness will simply plug into the back of the smoke detector and you will turn it counterclockwise to clip it in place.

how to install a wired smoke alarm

How To Install A Wired Smoke Alarm With Battery Back Up

Wiring a smoke detector with battery back up is basically the same principle as a hardwired smoke detector.

You will still need to hardwire the smoke detector with battery back up exactly the same way.

The difference is the hardwired smoke detector will have an additional 9 V battery inside the front casing. It’s 9 V battery will need to be changed every six months.

This is a common beep that you here once every minute that will drive you absolutely nuts. It is quite easy to change the battery the door simply clicks open and then the 9 volt battery will pop out.

They close attention to how the batteries installed it can be easily installed backwards.

Can I Install A Some Alarm To Work With Others?

Yes you can install a smoke detector to work with other smoke detectors.

That is what the red wires for for the interconnect between smoke detectors.

You will need to use a piece of 14/3 with a red, black and white to wire between the smoke detectors.

The wiring harness would work the same as a single smoke detector however you would connect a red wire search smoke detectors can talk to one another.

You will need to use an Octagon box to hold all the wiring behind the smoke detectors.

How Many Wired Smoke Alarms Can I Install On A Circuit?

We usually install up to 12 hard wired smoke detectors on a circuit.

We usually join them on with the lighting circuit as per code. This is done as there is not much of a load on any of the smoke detectors themselves.

They draw so little power that we don’t even consider them as part of the circuit.

Having said that the more smoke detectors you install on the same circuit the more likely you already have problems when it comes time to change the batteries.

Will Wired Smoke Alarms Work With My Old Battery Ones?

Hard wired smoke detectors are fussy . If you intend to link them together you will need to use the same brand name.

Mixing brand names well sent false signals between the smoke detectors and sent them off. They will also not work with old battery smoke detectors.

You can find out more on battery smoke detectors here.

Since the price of them is relatively cost effective it’s best to replace them all at once.

How Often Do I Have To Replace Smoke Alarms?

They should be replaced no more than every 10 years. In fact most smoke detectors have a date stamp bring on the side of them.

If they don’t have a date stamp on the side of them you should keep a log book as to when they were originally installed. Electronics grow week overtime and they may not do as good of a job sensing.

How To Install A Smoke Alarm As Part Of A Security System?

Installing a smoke detector as part of security system is usually a little bit different.

Security systems are usually low voltage or wireless. If there low voltage the never usually a point of wires in a pair of 2 will connect to the back of a smoke detector.

When smoke detector goes off it will break the circuit on the back of the 2 wires setting off the security system. These security systems are usually monitored.

Do I Need To Have Hardwired Smoke Alarms Inspected?

Most building codes state that you must have your smoke detectors inspected at the time of the construction of the house.

New homes require smoke detector on every level in every bedroom. This usually ends up with agent smoke detectors in a new home.

Most home inspectors will not give you an occupancy permit without the smoke detectors installed during the construction.

Your electrician can all the smoke detectors for you.

What If I Get The Wires Wrong?

If you get any of the wiring wrong on the back of the wiring harness then smoke detectors will not work.

Follow the diagram below to make sure that all the colors are matched up.

If the red interconnect wire is not wired up then the smoke detectors will not talk to one another.

It is important to get this step correct .

how to install a wired smoke alarm

Are There Different Kinds Of Hardwired Smoke Detectors ?

All hard wired smoke detectors heaven interconnect communicator. You must use the same brand name smoke detector.

Providing that is the same brand name you can mix and match different kinds of smoke detectors to do different things.

You can also get carbon monoxide smoke detectors an ionized smoke detectors.

If you try to mix different brand names they will not communicate properly or perhaps not work properly so make sure you get the same brand name in style.

Where In My House Do I Install Them?

On new construction smoke detectors are required in each bedroom or sleeping quarters.

They should be mounted next to the entry for doorway on the ceiling or no more than one foot down from the ceiling on the wall.

They should also be mounted in all hallways. Every level needs to have a smoke detector.

Including all of the high spots in home. Additionally you will want to add a smoke detector in your garage.

Do I Need To Have One In My Garage?

The garage smoke detector should be mounted up high on the ceiling away from the garage door. If you install a carbon monoxide detector it should be mounted lo on the floor on the wall.

Some smoke detector companies to make a combination of carbon monoxide and smoke together we should be mad at on the wall no more than one foot down from the corner of the ceiling.

This kind of smoke detector can interlink with your other home smoke detectors to let you know if there’s an issue with carbon monoxide.

More on the smoke detectors we recommend here.