Replacing Nest Protect in a Home With Wired, Interlinked Alarms

• Google stopped making Nest Protect; its help pages say it is no longer available for sale but is still supported, with existing units working until they expire
• In the US, Google steers customers to the First Alert SC5, an alarm that works with Nest Protect, and it names no replacement for the UK
• Google says a 2nd gen Protect has to be replaced 10 years after its manufacture date; the Replace by date is in the Nest and Google Home apps, with app warnings three months, one month and seven days ahead
• Once expired, it chirps continuously, and its light ring turns yellow at the nightly check
• First-time set-up and factory resets still need the Nest app, not the Google Home app

• One refund per household
• Homes where every Protect is close to its replacement date may not qualify
• Refunds are paid as Google Store credit or by bank transfer

• Protects interconnect only wirelessly, over Weave on 802.15.4, within about 15 m, and the link keeps working if the Wi-Fi drops
• Wired 230 V and battery Protects interconnect with each other
• Google says Nest Protect cannot communicate or interconnect with smoke or CO alarms from other manufacturers
• Google's UK wired guide says there is no need for the interconnect wire, and to insulate it if there is one

• A new alarm in place of an existing mains alarm, in the same position on the same circuit, is a replacement and not notifiable
• Adding a mains alarm that takes its supply from an existing lighting circuit is also not notifiable, as an addition to that circuit
• Running a dedicated alarm circuit from the consumer unit is notifiable work for a registered electrician, which JACK does not book
• Brands use their own base plates, so a new alarm usually goes up on its own base over the existing box

• A smoke alarm on every storey with a room used as living accommodation, a duty on private landlords since 1 October 2015
• A carbon monoxide alarm in each room used as living accommodation that contains a fixed combustion appliance, gas cookers aside, required since 1 October 2022, when social landlords came under the rules too
• A bathroom or lavatory counts as living accommodation, so one with a gas boiler needs a CO alarm
• Alarms checked on the day a new tenancy begins, and repaired or replaced as soon as reasonably practicable after a tenant reports a fault
• The regulations do not say whether alarms must be mains or battery powered

• Each alarm on the ceiling, with its label or Replace by date if you can see it
• Whether each is battery or wired: Google says a green light on the front marks a wired Protect
• The replacement alarms you have bought or plan to buy

A vetted pro prices your Nest job from the model and your photos, and the JACK app shows that fixed price before you book.

On heating, where the Heat Link goes moves the price most: a 3rd gen Heat Link in place of a programmer on the same wiring is the plainest job, while hot water on a cylinder, an S-plan or Y-plan wiring centre or an old wired thermostat to take out of the circuit adds to it. Anything that must be wired at the boiler itself is left out of the price and handed to a Gas Safe registered engineer.

On doorbells and cameras, power comes first: a battery doorbell or Nest Cam with a good 2.4 GHz signal is the lightest job, a weak bell transformer is swapped on its existing supply, and the Nest Cam with floodlight is priced as electrical work on your outside-light circuit. For a camera high on a gable, your pro can ask another pro on JACK to help through the Pro2Pro feature.

JACK does not sell devices, so the Nest kit is yours to buy. Accessories the job needs, such as a bell transformer, a fused spur or an outdoor junction box, are agreed and added at cost before you book, and so is parking where it has to be paid for. Several devices go on one booking for one fixed price. Prefer to pay for time? As a guide, hourly hire is typically £45–£95 per hour for smart home work and £55–£110 per hour for electrical work, and a full-day handyman booking is a flat £350–£400 for up to 8 hours on site.