Radio-Interlinked Combined Optical Smoke and Heat Alarm (Thermoptek) - FireAngel WST637
OPEN 7 DAYS A WEEK 0800 612 6537 Lines open today 8am - 9pm

Radio-Interlinked Thermally Enhanced Optical Smoke Alarm (Thermoptek) - FireAngel WST637

Discontinued Product

This product has been discontinued and is no longer available to buy.

View Alternative Product
Product Overview

The FireAngel WST637 contains an optical smoke alarm with built-in radio-frequency technology, allowing up to 50 alarms to be wirelessly interlinked and form a system. With thermally enhanced optical smoke sensing technology, the WST637 provides quick detection to slow smouldering fires, and has the added benefit of a sealed 10 year lithium battery, designed to last the life of the alarm.

Exclusive Extras from Safelincs

The FireAngel WST637 Optical Smoke Alarm Kits are supplied as standard with some exclusive extras that make purchasing these alarms easier and more cost-effective, including:

Product Features

  • Battery powered smoke alarm - 10 year sealed lithium battery
  • CE marked and LPCB tested to BS EN 14604
  • Test and hush button feature
  • Can be wirelessly linked with up to 50 radio-interlinked alarms
  • An interlinked system provides the earliest possible warning of fire
  • Radio-frequency range: 200m in free space, up to 35m in buildings
  • Fitted with a thermally enhanced optical smoke sensor
  • Quicker at detecting smouldering fires (compared to standard optical sensors)
  • Ideal for areas adjacent to the kitchen (not suitable for kitchen or garage)
  • Locate function allows you to find the alarm that activated the system
  • Suitable for installations complying to BS 5839-6: 2013 Grade F
  • Supplied with fixings; 2 x screws and 2 x rawl plugs

The table below shows all the units that can interlink with the FireAngel radio-interlinked series.

Alarms from the Same Series

Model Number
Type of unit
Type of interlink
WST637 Optical Smoke Alarm Radio-interlinked
WHT637 Heat Alarm Radio-interlinked

Compatible Alarms

Model Number Type of unit Type of interlink
WST-230 Mains Powered Optical Smoke Alarm Radio-interlinked
WHT-230 Mains Powered Heat Alarm Radio-interlinked

Carbon Monoxide Alarms

Model Number
Type of unit
Type of interlink
W7-CO-10X Carbon Monoxide Alarm Radio-interlinked

Ancillary Products

Model Number
Type of unit
Type of interlink
W2-SVP-630 Wireless Strobe and Vibrating Pad Radio-interlinked
W2-LFS-630 Wireless Low Frequency Sounder Radio-interlinked
Technical Data

Technical Data

This is the technical data for the Radio-Interlinked Thermally Enhanced Optical Smoke Alarm (Thermoptek) - FireAngel WST637.

Product Code FAWST637
Alternative Product Codes WST637, WST-637, WST630Q
Weight 0.27kg
Dimensions (HxDia) 41x132mm
Battery Type 10 year sealed lithium battery
Sound Output 85dB at 3 metres
Radio Linking Frequency 868.3MHz
Radio-Frequency Range Free Space: Up to 200m
In Buildings: Up to 35m
Operating Temperature +4 °C to +38 °C
Relative Humidity (non-condensing) Up to 90%
FAQs (15)

Q. What smoke alarm should I use in a bedroom with an en suite bathroom?

A. It is usually recommended to install an optical smoke alarm in a bedroom. This is because optical smoke alarms are slightly quicker at detecting slow smouldering fires that can originate from upholstery type materials and over-heated wiring. Also, an optical smoke alarm would be less likely to sound a false alarm than an ionisation would, if steam/water droplets were present from the bathroom. Detectors should be installed as central to the room as possible; however for your application I would also consider the position of the en suite to make sure that the detector is not in the direct path of the joining door. This is just to try and avoid the chances of a false alarm. No detector is designed for use in bathroom areas.

Q. How do I safely dispose of my old smoke alarms?

A. Safelincs is signed up to Valpak's WEEE (Waste Electrical and Electronic Equipment) Distributor Take-Back Scheme (Registration ID: 7370). Private households can therefore drop off their electronic and electrical fire safety waste at their municipal recycling centre when they are purchasing new products from us. To find your nearest recycling centre, please visit

Q. If the radio interlinking signal on one unit fails will the units still work as stand alone units.

A. Yes, should the radio interlinking signal fail the units will continue to sound independently should they detect a fire.

Q. Can a wireless router interfere with the radio interlinked alarms?

A. A wireless router is very unlikely to interfere with the signal of your radio interlinked alarms, as the RF signal of the smoke alarms is digitally coded.

Q. Do I need to take out all the batteries in my radio-interlinked alarms before adding a new alarm into the system?

A. No, you do not need to remove all the batteries. Just simply press the house code button on all the units. Please ensure that the batteries have full power as this could render the house code process incomplete.

Show all FAQs

Key Product Features

Easy-to-use test and hush button in the centre

Powered by a sealed 10-year long life battery

Status indicator lights around the main button

Includes screws and rawl plugs for installation

Product Dimensions

What's Included?

  • 1 x FireAngel WST-630 optical alarm
  • 1 x Sealed 10-year lithium battery
  • 1 x Screw fixing set (screws & rawl plugs)
  • 1 x Instruction manual

Product Datasheets

Customer Reviews

22 customers have have given this product an overall rating of 4.7 out of 5

Reviews by real customers

All of our product reviews are written by real customers that have purchased this product from us and are published without modification.

Rating: 4 / 5 Stars

Reviewed by: KE

Fitted and tested fine Cannot give a proper review as it's a product that has to work over a long period of time, which has not yet elapsed.

Published on: 23rd December 2018

Rating: 5 / 5 Stars

Reviewed by: MW

Superb product, exactly what we needed for building regulations, fast efficient service.

Published on: 6th November 2018

Rating: 5 / 5 Stars

Reviewed by: AR

Excellent product, pre-connection service made setup easy too. Very help assistant who helped guide me on the products available and to identify the right product.

Published on: 22nd April 2018

Rating: 5 / 5 Stars

Reviewed by: SS

Just bought so difficult to tell in the long term, but so far so good. Very professional service

Published on: 4th February 2018

Rating: 5 / 5 Stars

Reviewed by: RM

Linking of alarms and general use very straightforward to date.

Published on: 17th October 2017

Rating: 5 / 5 Stars

Reviewed by: LC

Very easy to install

Published on: 31st July 2017

Rating: 5 / 5 Stars

Reviewed by: TM


Published on: 5th June 2017

Rating: 4 / 5 Stars

Reviewed by: KW

Easy enough to fit and program, signal penetraes several floors of house and ensure I can hear it going off in the loft.

Published on: 23rd January 2017

Rating: 5 / 5 Stars

Reviewed by: PM

Excellent - just works

Published on: 13th January 2017

Rating: 5 / 5 Stars

Reviewed by: RD

Great alarm easy to set up (especially when safelincs link then for you!). Have this in hall close to kitchen and upstairs, not affected by kitchen activity however the upstairs unit is triggered by steam from the bathroom but this is to be expected (especially as our bathroom ends up like a stream room). Very good alarm for price

Published on: 24th November 2016

Rating: 4 / 5 Stars

Reviewed by: DB

Really pleased with this product. Not so pleased to see it a lot cheaper in Homebase, but can at least get an extra one to link in with the two I purchased from you.

Published on: 4th November 2016

Rating: 5 / 5 Stars

Reviewed by: TE

as above

Published on: 12th June 2016

Rating: 4 / 5 Stars

Reviewed by: BM

Very pleased with this product.easy to fit.

Published on: 1st May 2016

Rating: 5 / 5 Stars

Reviewed by: JB

Fumes kill you before the heat. Brilliant product, and the WiFi interlinkage sets off all devices if just one is triggered giving mote time to escape danger. I feel much safer in our home now.

Published on: 18th April 2016

Rating: 5 / 5 Stars

Reviewed by: MM

Great product. Great product. The fact they are interlinked and give a ten year use with sealed batteries means they comply to self-catering accomodation rules

Published on: 18th April 2016

Rating: 4 / 5 Stars

Reviewed by: SP


Published on: 27th March 2016

Rating: 5 / 5 Stars

Reviewed by: GM

brilliant thatched house got one in loft talking to others Needed interconnected alarms for thatched house insurance. Insurance surveyor impressed asked me where I got it from. No wires or batteries required programming took 5 mins just press the buttons and they find each other. Would definitely recommend

Published on: 13th March 2016

Rating: 5 / 5 Stars

Reviewed by: IH

Nice unit that's easy to install

Published on: 16th February 2016

Rating: 4 / 5 Stars

Reviewed by: -

easy to set up

Published on: 27th January 2016

Rating: 5 / 5 Stars

Reviewed by: -

Brilliant Product & very easy to fit.

Published on: 21st January 2016

Rating: 5 / 5 Stars

Reviewed by: -

The units were very easy to install and easily linked.

Published on: 24th November 2015

Rating: 5 / 5 Stars

Reviewed by: -

Pre-synchronised takes the pain away Free synchronisation between two alarms meant this product was fit for purpose out the box. We know it works well both pressing the "test" button and by burning toast! Making a decision about adopting this model took a while (plenty of options) but this ticks all our boxes..

Published on: 12th November 2015

Show All

Excellent Warranty

This product is supplied with a 7 year manufacturers warranty as standard

FireAngel Wi-Safe 2

Play Video
Run Time: 00:43

FireAngel Thermoptek Sensor Technology

Play Video
Run Time: 00:42

FireAngel Long-Life Batteries

Play Video
Run Time: 00:42

Looking for more information?

If you have any questions or would like more information about this product you can ask one of our specialists.

Live Chat Available Now
Direct Telephone 01507 464181
Direct Email Email Now


Close close

This site uses cookies to improve your experience and for essential functioning of the site. By continuing to use our site you agree to the use of cookies.

Change your cookie settings at any time by clicking on the button at the bottom of each page. Read more about the cookies we use in our Privacy Policy.

By continuing to browse this site you agree to the use of cookies. Read our privacy policy to learn more.