Google Nest Protect Replacement and Fitting in London

• A 2nd gen Nest Protect must be replaced 10 years from its date of manufacture, not from the day it went up
• The Nest app warns three months, one month and seven days before that date, and shows the date in the device's technical information
• Once it expires, the light ring turns yellow and the alarm chirps continuously
• The 1st gen has a square backplate and straight edges; the 2nd gen is rounded with a battery door, and a green light on the front marks a wired unit

• For US customers, Google's help points to the First Alert SC5, and it names no UK equivalent
• Where a compatible replacement isn't available in your region, you may be eligible for a pro-rata refund: one per household, paid as Google Store credit or by bank transfer, though homes where every Protect is near its replace-by date may not qualify
• Nest Protect can't interconnect with other makers' alarms, so a new brand in one room will not sound with the Protects left in the others
• Look for smoke alarms to BS EN 14604 and CO alarms to BS EN 50291-1, the standards Google lists Protect as tested to; JACK does not sell alarms, so you choose and buy them

• A new alarm on the same mains wiring in the same position is a replacement, which nobody has to notify to building control
• A new mains alarm fed from an existing lighting circuit is an addition to that circuit, which is not notifiable outside a bathroom either
• A new dedicated alarm circuit from the consumer unit is notifiable, so it needs a registered electrician and JACK does not book it
• Google's UK wired guide recommends professional installation, connects live, neutral and earth in a junction box, and says to insulate any interconnect wire, because Protects link wirelessly

• Private landlords have had to fit a smoke alarm on every storey with living accommodation since 2015, and a CO alarm in any room with a fixed combustion appliance other than a gas cooker since October 2022, when social landlords were brought in too
• Each alarm is checked on the day a new tenancy begins, and one reported faulty is repaired or replaced as soon as reasonably practicable
• A bathroom counts as living accommodation, so in a rented home one with a gas boiler needs a CO alarm
• The regulations do not set a power type; gov.uk's landlord guidance says sealed-for-life batteries are the better option where battery alarms are chosen
• New homes and some building work follow Approved Document B: at least a Grade D2 Category LD3 system to BS 5839-6, with mains smoke alarms and a standby supply

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.