FireAngel FA3322 vs Kidde K7CO: choosing a battery carbon monoxide alarm

Confirm the exact model and the household requirement

Read the full model reference and current supplied documentation before ordering. FireAngel uses FA3322 and FA3322-EUX10 naming, while Kidde also sells similarly named models with different displays or power arrangements. A listing photograph or the phrase ten year is not enough to establish which variant you will receive.

Check the requirements for your UK nation, tenancy and building with the responsible landlord or appropriate adviser. Requirements differ, and a product comparison cannot confirm compliance for a particular property. Both manufacturer pages list EN 50291 approvals, but you still need the correct alarm, application and current instructions. Ask about an appropriate alerting arrangement if a person may not hear a standard alarm.

• Keep smoke, heat, CO and CO2 monitoring requirements distinct.
• Use a verified supplier and check the exact model documentation.

FireAngel FA3322-EUX10: display and sealed power

FireAngel lists a ten-year lifetime sealed battery, an electrochemical CO sensor and a multifunction LCD. The display provides CO information alongside temperature and humidity readings, with visual instructions and colour changes for different events. The model also includes low-level monitoring and alarm-memory features described by the manufacturer.

This design is worth shortlisting if readable visual information is useful to the household and a sealed power source suits its maintenance plan. It does not remove the need for the prescribed checks or action when the alarm signals. Environmental readings are an additional feature, not a complete indoor-air assessment or a reason to dismiss symptoms.

• Check that the intended user can read and understand the display.
• Retain the manual for the exact unit and its signal meanings.

Kidde K7CO: replaceable batteries and simpler indicators

Kidde specifies two AA alkaline batteries, a ten-year sensor, multifunction LEDs, a test/reset button and an end-of-life warning. The K7CO has no digital CO display; K7DCO is a different model. Its ten-year sensor description must not be read as a promise that the supplied AA batteries last ten years.

A simpler indicator layout may suit someone who wants a conventional alarm without additional environmental readings. The tradeoff is a continuing battery-maintenance responsibility under the instructions. Keep the correct battery information with the household plan and make sure an authorised person can respond to maintenance signals. Do not silence a warning and leave the cause unresolved.

• Distinguish battery replacement from replacing an end-of-life unit.
• Read any boat or caravan approval limits separately if relevant.

Choose a maintenance plan as well as an alarm

Shortlist the FireAngel when sealed power and the extra visual information meet a clear need. Shortlist the Kidde when its indicator-based design and replaceable-battery routine suit the household and local requirements. If a correctly specified existing alarm is in date, maintained and suitable, replacing it solely for an LCD may not be the best use of the budget.

An alarm does not make an unsafe appliance safe. Keep fuel-burning equipment professionally maintained and required ventilation unobstructed. Never use outdoor combustion equipment indoors or in a garage. If CO exposure is suspected, follow NHS and emergency-service advice, move to fresh air and seek help; do not wait for a display reading to decide whether illness matters.