Kidde K4MCO User manual

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User Guide
230V MAINS
CARBON MONOXIDE ALARM
WITH RECHARGEABLE
BATTERY BACKUP
WARNING : This alarm will not operate
without Mains power. During a power failure
the unit will operate for at least 72 hours on
battery back up.
Type B apparatus
Model K4MCO
EN 50291-1:2018
LICENSE NO. KM 738897
P/N: 2512-7245-01
KM 738897
BS EN 50291-1:2018

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Contents
1. Diagram of Alarms......................................................................................................................................................................................... 3
2. What is Carbon Monoxide?..................................................................................................................................................................... 4
3. Safety Information......................................................................................................................................................................................... 5
4. Installation Instructions – Recommended Locations...............................................................................................................7
5. Using Your Alarm-what the signals mean.....................................................................................................................................11
6. Mains Power Failure.....................................................................................................................................................................................13
7. Interconnected systems.............................................................................................................................................................................14
8. What to do if Your Alarm Sounds!.......................................................................................................................................................16
9. Maintenance of Your Alarm.....................................................................................................................................................................17
10. Troubleshooting............................................................................................................................................................................................ 17
11. Product Specifications............................................................................................................................................................................... 18
12. Warnings and Important Notices....................................................................................................................................................... 19
13. Service and Warranty................................................................................................................................................................................. 21
14. Environmental Protection....................................................................................................................................................................... 22

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1. Diagram of Alarm
Green,
Power LED
Test / Reset
Button
Model K4MCO
Red,
Alarm LED
FAULTPOWERALARM
MOVE TO FRESH AIR
Model: K4MCO
CARBON MONOXIDE ALARM

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Carbon monoxide is a cumulative poison. Longterm exposure to low levels may cause symptoms.
This alarm is time-weighted – the higher the level of CO, the sooner it will alarm.
NOTE: The apparatus may respond to brief exhaust gas emissions, for example during the initial start-up of an
appliance. Also, hydrogen acts as an interferent and can arise from some battery charging activities and the curing
of concrete or cement under certain circumstances. Volatile Organic Compounds (VOCs), e.g. alcohols, which may
eventually activate the alarm, can be generated from use of damp-proofing materials or other coatings containing
alkylalkoxysilanes.
2. What is Carbon Monoxide?
This CO alarm is not a substitute for proper
installation, use and maintenance of fuel burning
appliances including appropriate ventilation and
exhaust systems.
Carbon monoxide can be produced from poorly
burning appliances or from blocked flues and
chimneys.
If your alarm has sounded and you have ventilated
the room the CO may have dispersed before help
arrives. It is crucial that the source of CO is
determined and appropriate maintenance carried
out.
POTENTIAL SOURCES OF CO
• Wood-burning stoves
• gas boilers and Fires
• gas Hobs
• oil and coal burning appliances
• portable gas Heaters
• blocked Flues and cHimneys
• Fumes From integral garages
• barbecues
• HigH concentrations oF tobacco smoke

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To be safe, know the possible sources of CO in your home. Keep fuel burning appliances and their chimneys and vents in
good working condition. Learn the early symptoms of exposure, and if you suspect CO poisoning, move outside to fresh
air and get emergency help. Your first line of defence is an annual inspection and regular maintenance of your applianc-
es. Contact a licensed contractor or call your local utility company for assistance.
In rented properties your Landlord (or Council/ Housing Association), will have an Emergency Response phone
number, and be liable for the regular maintenance of their combustion appliances (Gas/LPG/Oil/Solid Fuel).
This alarm has not been tested specififically for use in caravans or boats. Only CO alarms certifified to
EN50291-2 are fully approved for this purpose.
Teach children how to respond to the alarm and that they should never play with the unit. This alarm is designed to
detect carbon monoxide from any source of combustion in a residential environment.
NOTE: Please thoroughly read this user guide and save the document for future reference and to pass on to any subse-
quent owner.
IMPORTANT: Additional markings can be found on the back of the unit.
The manufacturer recommends replacing this alarm seven years from the install date on the side of alarm. Product
contains sealed in lithium batteries. Removal can be done only by qualied professionals in recycling points.
Seven (7) years after the unit was installed, this unit will automatically alert you that it is time to replace the unit.
This is called “End of Unit Life” mode. To help track the life of your alarm, write the installation date in the space
provided on the side of the alarm. A label has been provided that has important information on what to do in case of a
CO alarm. Place the label at eye level on a wall near the alarm after it is mounted.
This alarm is not intended to alert hearing impaired individuals.
Alarm levels as defined by EN50291-1:2018
The table below shows the response times at which your CO alarm will sound.
3. Safety information
PParts per Million (PPM) of COof C TITime until Alarm
50 60  90 Minutes
100 10  40 Minutes
300 Must alarm in less than 3 minutes

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NOTE: If at any time your alarm fails to operate correctly (erratic or low sound, for example), or if you require further information,
please contact customer support at 0800 917 0722.
PParts per Million (PPM)
of CO
TiEffects on Adults
100 Slight headache, nausea, fatigue (flu-like symptoms)
200 Dizziness and headache within 2 – 3 hours
400 Nausea, frontal headache, drowsiness, confusion and rapid heart rate. Risk to life after
over 3 hours of exposure
800 Severe headaches, convulsions, vital organ failures. Death possible within 2 – 3 hours
CO Advice and Information
The table below shows the effects of different levels of CO poisoning on the body.
Important Safety Information
NOTE: If you recognise any of the above symptoms consult your Doctor immediately.
NOTE: Young children, elderly and pets are more susceptible to the dangers of CO.
NOTE: Your alarm is designed to detect CO gas. It is not designed to detect smoke, fire or other gas such as
natural gas.
NOTE: This product is intended for use in ordinary family homes. It is not designed to measure compliance with
occupational safety and the HSE.
NOTE: Individuals with certain specific medical conditions may need an alarm that operates below 30ppm.
If this applies consult your Doctor.
IMPORTANT: Ensure that all family members are familiar with the symptoms of CO poisoning and how your
alarm works.

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4. Installation Instructions – Recommended Locations
NOTE: CO alarms should be installed following the guidance of relevant local standards, such as EN 50292.
•Whether the alarm is wall-mounted or ceiling mounted, place the alarm a horizontal distance of between 1 metre
and 3 metres from a fuel burning appliance.
•When mounting the alarm on the wall, use an inside wall with the top edge of the alarm at a minimum of 150 mm
below the ceiling, and the bottom edge of the alarm within 300 mm below the ceiling. The bottom of the alarm
should also be at a level greater than the height of any door or window.
•Locate within hearing distance of bedrooms* and place at sleeping height if a heating appliance is in the bedroom.
•CO alarms in rooms with sloped ceilings should be located on the high side of the room.
•Ceiling mounted alarms should be at least 300 mm from any wall.
•If there is a partition in the room, locate the alarm on the same side of the partition as the potential source.
* A CO alarm should be installed in all rooms containing a fuel burning appliance. Additional CO alarms should be
installed in rooms where most awake time is spent, in every sleeping area, and on every level of the home.

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Locations to Avoid
•In the garage. Products of combustion are present when you start your motor vehicle.
•Do not install alarms adjacent to, or directly above, heaters or air-conditioning vents.
•In very humid areas (above 90% RH, non-condensing), such as bathrooms and shower rooms. Do not install directly
above a sink, or near dishwashers or washing machines. Moisture or steam can cause nuisance alarms.
•Do not install within 1 m of heating or cooking appliances, measured horizontally.
•In an area where the temperature may fall below 0 ºC or rise above 40 º C such as garages and unfinished attics.
•Do not install alarms in dusty areas. Dust particles may cause nuisance alarm or failure to alarm.
•In insect-infested areas.
•Within 300 mm of a light fitting, as electronic “noise” generated by the electronics may cause nuisance alarms.
•Do not install in an enclosed space (cupboard) or where the ventilation openings in the unit could be impeded by
items such as newspapers, table-cloths, furniture, curtains, etc.
•Do not install next to a door, window, extractor fan, flue, chimney, or any other area where high air flow may occur or
the unit may be directly exposed to weather.
•Do not install in locations that are difficult or dangerous to reach for testing or maintenance.
WARNING: TO REDUCE THE RISK OF FIRE OR ELECTRIC SHOCK, DO NOT EXPOSE THIS PRODUCT TO RAIN OR MOISTURE.

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4. Installation Instructions –Supply and Interconnect
Wiring Requirements
•This alarm is designed for installation by a qualified electrician in accordance with local wiring regulations and in
regard to relevant building regulations and codes of practice. In addition, the resistance of the interconnect wiring
shall be a maximum of 10 ohms.
•An appropriate all-pole disconnection device shall be provided as part of the building installation.
•The maximum wire run distance between the first and last unit in a hardwired interconnected system is 300 m.
•When alarms are hardwire interconnected, all interconnected units must be powered from a single circuit.
•This alarm must be powered by a constant 230V AC, 50Hz supply that is not controlled by any form of switch.
•This alarm interconnects with up to 24 other devices (of which 18 can be initiating) including smoke, CO and heat
alarms. (See below). This alarm is not designed to be interconnected with other manufacturer’s products, unless
otherwise specified.
WARNING: The alarm cannot be operated from power derived from a square wave modified square wave or
modified sine wave, inverter. These types of inverters are sometimes used to supply power to the structure in off grid
installations , such as solar or wind derived power sources. These power sources produce high peak voltages that will
damage the alarm.
Interconnect Wiring
Line (L)
Neutral (N)
House cabling in compliance with local regulations
Interconnect (I/O)*
Brown Blue
White* White*
Brown Blue
NOTE: Use standard British Standard household cable PVC/PVC 6242Y / 6243Y or equivalent in accordance with local regulations.

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WARNING: Turn off the main power to the circuit before wiring. Route the AC supply/interconnect cable into the dry
lining box or Kidde surface pattress
•Affix the CO alarm mounting plate to the dry lining box or Kidde surface pattress using suitable screws.
•Using a suitably-rated terminal block, connect the neutral supply to the blue wire of the connector plug and the live
supply to the brown wire.
•If interconnecting is required, connect the white wire of the connector plug to the designated interconnect
conductor of the 4-core supply cable.
•NOTE: Do not use an earth wire for the interconnect conductor.
•NOTE: If this is to be a single-station CO alarm, connect the white wire to an unused terminal block.
•Attach the connector plug to the back of the CO alarm. The plug will only fit one way and will snap into place.
•Slide switch on rear of alarm to on position.
•Align alarm with mounting plate and rotate clockwise into place.
•Test CO alarm. See section 5 “Testing”.
WARNING: Failure to properly install and activate this alarm will prevent proper operation of this alarm and will
prevent its response to CO hazards.
Interconnect Model Capability
Pf FirexCO TiKIDDE
KF10R 1SFWR Mains Ionisation Alarm with rechargeable battery back-up
KF10 1SFW Mains Ionisation Alarm with alkaline battery back-up
KF20R 2SFWR Mains Optical Alarm with rechargeable battery back-up
KF20 2SFW Mains Optical Alarm with alkaline battery back-up
KF30R 3SFWR Mains Heat Alarm with rechargeable battery back-up
KF30 3SFW Mains Heat Alarm with alkaline battery back-up
4MCO Mains CO Alarm with rechargeable battery back-up
4MDCO Mains CO Alarm with rechargeable battery back-up, digital display
K4MCO Mains CO Alarm with rechargeable battery back-up

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5. Using Your Alarm – what the signals mean
Operational Mode TiLEDs Sounder Unit Status Action
Normal Operation Red None Normal Operation None
Amber
Alarm
Red Flashing 4 loud beeps/pause/
4 loud beeps- repeated CO detected. See section
Amber
Interconnected CO
alarm detects CO
Red Flashing 4 loud beeps/pause/
4 loud beeps- repeated
Interconnected CO alarm
detects CO. See section
Amber
Interconnected
Heat/Smoke alarm
detects hazard
Red Flashing 3 loud beeps/pause/
3 loud beeps- repeated
Smoke or heat has been
detected from an intercon-
nected smoke or heat alarm.
Evacuate the premises
according to your
escape plan
Amber
Error condition -1
Red Flashing every 30 secs
Chirp/30 secs Unit has failed. Replace
Amber Flashing every 30 secs
Error condition -2 Red ON Constant loud sound Unit microprocessor has failed. Replace
Amber
End of Life Red Flashing Chirp twice every
30 seconds
The unit has reached the end
of its life. Replace
Amber
Flashing twice every 30 secs
Charging the bat-
tery back up
Red NONE Battery backup is charging
(unit is monitoring for CO). Nothing
Amber
Flashing every 15 secs
Low battery
Red
Flashing every 15 secs
Chirp/15 secs Back up battery is discharged.
Ensure switch is On
at the rear of the unit
- if it persists contact
customer service.
Amber
Flashing every 15 secs
NOTE: If AC mains is connected and active, the Green LED will be on continuous. If Green LED is not on, see Section 6.

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5. Using Your Alarm – Cont.
Testing
Each week your alarm should be tested by pressing the test button. The alarm will beep once followed by a brief
pause. Then the alarm will sound fully with 4 beeps a pause and then 4 beeps. If the alarm does not sound, or gives
erratic or low volume sound, the unit must be replaced.
During testing the red LED will flash.
This confirms that the alarm is powered up and working.
WARNING: DUE TO THE LOUDNESS OF THE ALARM, ALWAYS STAND ABOUT 1 METRE AWAY FROM THE UNIT OR
USE EAR PROTECTION WHEN TESTING.
Re-setting the Alarm
If the alarm sounds, the test / reset button will silence the alarm unless it is still detecting dangerous levels of CO.
End of Life Notification
After 7 years of continuous operation, the unit will chirp twice every 30 seconds, and the amber LED will flash twice.
The red LED will also be flashing. Unit has reached end of life, and must be replaced. Follow the instructions on the
back of the unit to slide the battery switch to “OFF” before disposal.
NOTE: Constant exposures to extreme temperatures and humidities may affect battery life.

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6. Mains Power Failure
iLEDs Sounder Unit Status Action
Loss of Mains power
Red OFF
Unit has no mains power and
the battery back up will have
limited life
Restore the mains
ASAP
Green Flashing every 7 secs
Amber OFF
Low Battery when
mains has failed
Red Flashing every 15 secs
Chirp/15 secs Back up battery is discharged Restore the mains
ASAP
Green Flashing every 7 secs
Amber Flashing every 15 secs
Battery back up
close to discharge
Red Flashing every 60 secs
Chirp/60 secs Unit will no longer detect CO Restore the mains
ASAP
Green Flashing every 7 secs
Amber OFF

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7. Interconnected systems
Interconnected systems of Kidde Models - 1SFW, 1SFWR,
2SFW, 2SFWR, 3SFW, 3SFWR, 4MCO, 4MDCO, K4MCO
CO alarm Smoke/Heat Alarm
Press CO test button Normal test sequence - 4 loud beeps
pause and then 4 loud beeps and so on. Do not sound.
Press Smoke/Heat
Alarm test button
3 loud beeps pause 3 beeps with
Red LED flashing 3 loud beeps pause 3 loud beeps with Red LED flashing
Smoke/Heat Alarm
Event
3 loud beeps pause 3 loud beeps with
Red flashing. The Digital model will
display “ Fire”
3 loud beeps pause 3 loud beeps with Red flashing.
CO event Alarms with 4 loud beeps pause 4 beeps
and so on. Do not sound.
Smokes/Heat alarm will overide CO

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Interconnected systems of Kidde, Firex models:
KF10, KF10R, KF20, KF20R, KF30, KF30R
CO alarm Smoke/Heat Alarm
Press CO test button Normal test sequence - 4 loud beeps
pause and then 4 loud beeps and so on.
Normal test sequence - 4 loud beeps
pause and then 4 loud beeps and so on.
Press Smoke/Heat
Alarm test button
3 loud beeps pause 3 beeps with
Red LED flashing 3 loud beeps pause 3 loud beeps with Red LED flashing
Smoke/Heat Alarm
Event
3 loud beeps pause 3 loud beeps with
Red flashing. 3 loud beeps pause 3 loud beeps with Red flashing.
CO event Alarms with 4 loud beeps pause 4 beeps
and so on. Alarms with 4 loud beeps pause 4 beeps and so on.
Smokes/Heat alarm will overide CO

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8. What to do if Your Alarm Sounds!
Carbon Monoxide Alarm Procedure
WARNING: CARBON MONOXIDE ALARM ACTIVATION INDICATES THE PRESENCE OF CARBON MONOXIDE (CO) AT HIGH
CONCENTRATIONS WHICH CAN KILL YOU.
Based on recommends from EN 50292, follow these steps if alarm sounds (4 loud audible pulses followed by a pause for 5 seconds):
1. Keep calm and open all doors and windows. Turn off all fuel-burning appliances if possible. Note: it is possible that outdoor
conditions could influence domestic CO alarms (bad traffic pollution in cold weather, for example). In these circumstances, the level
of indoor CO might actually increase when doors and windows are opened.
2. If the alarm continues to sound, even after being reset (where appropriate), then evacuate the premises, alerting other occupants to
the risk. Leave doors and windows open. Do not re-enter the premises.
3. Get medical help for anyone suffering the effects of CO poisoning, and advise that CO inhalation is suspected.
4. Call Gas Emergency Services: 0800 111 999, or your local Gas Safe Registered Engineer:
PHONE NUMBER:
Never restart the source of the CO problem until it has been corrected. Never ignore the sound of the alarm! If the alarm is sounding,
pressing the test/reset button will terminate the alarm. If the CO condition that caused the alert in the first place continues, the
alarm will reactivate. If the unit alarms again, it is sensing high levels of CO which can quickly become a dangerous situation.
CAUTION: If there is any question as to the cause of an alarm it should be assumed that the alarm is due to dangerous levels of
carbon monoxide and the dwelling should be evacuated.

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9. Maintenance of Your Alarm
This is a Mains Alarm. Isolate before removing for decorating. If in doubt contact a qualified electrician.
Warning: Do not tamper with the apparatus, as there is a risk of electric shock or malfunction. To keep your alarm in good
working order:
Your Alarm Should be Cleaned at Least Once a Year.
You can clean the interior of your alarm by using compressed air or a vacuum cleaner hose and blowing or vacuuming through the
openings around the perimeter of the alarm. The outside of the alarm can be wiped with a damp cloth. Use only water to dampen the
cloth, use of detergents or cleaners could damage the alarm.
If the alarm is in Fault mode, the alarm may be in need of cleaning. After cleaning, press the test button. If the fault does not clear, the
alarm needs to be replaced.
• Never use detergent or other solvents to clean the unit.
• Avoid spraying air freshener, hair spray, or other aerosols near the alarm.
• Do not paint the unit. Paint will seal the vents and interfere with the sensor’s ability to detect CO.
• Keep away from nappy buckets.
• Never attempt to disassemble the unit to clean inside. Altering the alarm in any way may lead to a risk of electric shock or prevent it
from functioning correctly. This action will void your warranty.
CAUTION: THIS UNIT IS SEALED. THE COVER IS NOT REMOVABLE!
NOTE: YOUR CO ALARM MUST BE INSTALLED BY A COMPETENT PERSON, AND IS TO BE INSTALLED ACCORDING TO THESE INSTRUCTIONS.
The following substances can affect the sensor and cause false alarms:
Methane, Propane, Iso-butane, Iso-propanol, Ethylene, Benzene, Toluene, Ethyl acetate, Hydrogen Sulphide, Hydrogen, Sulphur
Dioxide, alcohol based products, paints, thinners, solvents, adhesives, hair-sprays, aftershaves or perfumes and some cleaning agents.
NOTE: there could be other compounds occurring within a particular household which could cause similar effects.
• Move the Alarm and place in another location prior to performing any of the following:
Staining or stripping wood floors or furniture
Painting
Wall papering
Using adhesives
Storing the unit in a plastic bag during any of the above projects will protect the sensors from damage. When household cleaning
supplies or similar contaminates are used, the area must be well ventilated.
WARNING: REINSTALL THE ALARM AS SOON AS POSSIBLE TO ENSURE CONTINUOUS DETECTION.

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10. Troubleshooting
iLEDs Sounder Unit Status Action
Error condition -1 Red Flashing every 30 secs Chirp/30 secs Unit has failed Replace
Amber Flashing every 30 secs
Error condition -2
Red ON Constant lound
sound Unit microprocessor has failed Replace
Amber
End of Life
Red Flashing Chirp twice every
30 seconds
The unit has reached the end
of its life Replace
Amber Flashing twice every
30 secs
Low battery
Red Flashing every 15 secs
Chirp/15 secs Backup battery is discharged
Ensure switch is ON at
the rear of the unit-if it
persists, contact
customer service.
Amber Flashing every 15 secs
NOTE: If AC mains is connected and active, the Green LED will be on continuous. If Green LED is not on, see Section 6.

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Power 230V, 50Hz 30mA max
Sensor Electrochemical CO Sensor
Storage and Transport
Conditions 20 ºC TO +60ºC, 5  95% RH non-condensing)
Temperature Range Operating range: 0°C to 40°C
Humidity Up to 90% relative humidity (RH), non-condensing
Alarm Sound 85dB+ at 3 metres (10ft) @ 3.4 +/- 0.5 KHz pulsing alarm
Size and weight
Weight: 220g
Dimensions: 145mm x145mm x 40mm
11. Product Specifications

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12. Warnings and Important Notices
WARNING: THIS CARBON MONOXIDE ALARM IS NOT A SUBSTITUTE FOR INSTALLING AND MAINTAINING AN APPROPRIATE
NUMBER OF SMOKE ALARMS IN YOUR HOME. THIS ALARM WILL NOT SENSE SMOKE, FIRE, OR ANY POISONOUS GAS OTHER
THAN CARBON MONOXIDE. FOR THIS REASON YOU MUST INSTALL SMOKE ALARMS TO PROVIDE EARLY WARNING OF FIRE
AND TO PROTECT YOU AND YOUR FAMILY FROM FIRE AND ITS RELATED HAZARDS.
WARNING: THIS PRODUCT IS INTENDED FOR USE IN ORDINARY INDOOR LOCATIONS OF FAMILY LIVING UNITS. IT IS NOT
DESIGNED TO MEASURE COMPLIANCE WITH COMMERCIAL AND INDUSTRIAL STANDARDS. THIS ALARM IS NOT SUITABLE
FOR INSTALLATION IN HAZARDOUS LOCATIONS . INDIVIDUALS WITH MEDICAL PROBLEMS MAY CONSIDER USING WARNING
DEVICES WHICH PROVIDE AUDIBLE AND VISUAL SIGNALS FOR CARBON MONOXIDE CONCENTRATIONS UNDER 30 PPM.
IMPORTANT: THIS CARBON MONOXIDE ALARM IS DESIGNED TO DETECT CARBON MONOXIDE FROM ANY SOURCE OF
COMBUSTION INCLUDING IMPROPER OR MALFUNCTIONING APPLIANCES. THE INSTALLATION OF THIS DEVICE SHOULD NOT
BE USED AS A SUBSTITUTE FOR PROPER INSTALLATION, USE AND MAINTENANCE OF FUEL BURNING APPLIANCES INCLUDING
APPROPRIATE VENTILATION AND EXHAUST SYSTEMS
WARNING: THIS ALARM WILL NOT WORK WITHOUT POWER. THIS ALARM REQUIRES A CONTINUOUS SUPPLY OF POWER.
WARNING: THIS UNIT IS NOT A SMOKE ALARM. IT WILL NOT SENSE SMOKE . FOR EARLY WARNING OF FIRE YOU MUST
INSTALL SMOKE ALARMS.
IMPORTANT: IF ANY FAULT SIGNALS OCCUR, CONTACT THE MANUFACTURER OR SUPPLIER AND DO NOT CONTINUE USING
THE ALARM.
WARNING: THE DEVICE CANNOT WARN AGAINST THE CHRONIC EFFECTS OF EXPOSURE TO CARBON MONOXIDE OR
PROTECT INDIVIDUALS WHO ARE AT SPECIFIC RISK.
WARNING: ALTERING THE ALARM IN ANY WAY MAY LEAD TO A RISK OF ELECTRIC SHOCK OR PREVENT IT FROM
FUNCTIONING CORRECTLY.
CAUTION: THIS ALARM WILL ONLY INDICATE THE PRESENCE OF CARBON MONOXIDE AT THE SENSOR. CARBON
MONOXIDE MAY BE PRESENT IN OTHER AREAS.
This alarm does not prevent CO from occurring, nor can it solve any existing CO problem.
WARNING: THIS DEVICE IS DESIGNED TO PROTECT INDIVIDUALS FROM ACUTE EFFECTS OF CARBON MONOXIDE
EXPOSURE. IT WILL NOT FULLY SAFEGUARD INDIVIDUALS WITH SPECIFIC MEDICAL CONDITIONS. IF IN DOUBT, CONSULT A
MEDICAL PRACTITIONER.
This alarm has not been investigated for carbon monoxide detection below 50 PPM.