Part Six – Frequently Asked Questions
Q.How many alarms do I need in my house? How much square footage will one alarm cover?
A.We recommend you place alarms near the sleeping area(s). If you have a
Generally, one alarm can be adequate for 1,200 to 1,500 square feet of living space. The most important determination for the number of units needed is whether an alarm can be heard in all sleeping areas.
Q. Can you explain what
The microchip inside your Nighthawk CO alarm monitors the air for the presence of carbon monoxide and computes the levels and length of exposure, alarming when you should be con- cerned about CO exposure.
For more information about the alarm, see page
Q. Do I have to press the test button to get a CO reading? A. No. Your Nighthawk CO alarm continuously monitors the air for carbon monoxide. An updated reading is shown on the dig- ital display every 15 seconds. If there is no CO present, the dig- ital display will show a zero. The alarm will alert you to the pres- ence of CO automatically.
To test the internal components and circuitry of your alarm, press the Test/Reset button. For complete instructions on testing your alarm, see page
Q.What happens if the power goes out?
A.If a good battery is in the unit, the alarm will display a blink- ing dot at least 20 hours while still providing protection against CO exposure. Please see page
Q.How do I get the alarm to show something besides “0.” OR, How can I determine if the sensor is operating correctly?
A.Please refer to “Testing Sensor Response” on page
Q.You warranty the alarm for five years. How will I know when it doesn’t work anymore and I need to buy a new one?
A.In any event of malfunction, your alarm will alert you with malfunction signals. These signals are described in detail on page
Q.What do the numbers mean on the digital display when
Ipress the “Test/Reset” button?
A.The numbers you see when you press the Test/Reset button are NOT a CO reading. This is a simulated reading the alarm dis- plays as it tests its electronics. The numbers displayed when the Test/Reset button is pushed should be between 100 to 400 (usu- ally around 200).
Q.I called in someone to inspect my home for CO after my unit alarmed, and he couldn’t find anything wrong. Why? Does that mean this unit “false alarmed”?
A.No. Please read the information explaining why a CO prob- lem can be difficult to diagnose on page
Q.I tried to test the alarm (see below) and it still reads “0.” Why?
–by running the car in the garage
–by holding it to the tailpipe of the car
–by putting it next to the furnace vent
A.DO NOT try to test your alarm by doing any of the above! Testing the alarm using any of the methods listed above usually does not yield satisfactory results and could in fact be dangerous. To accurately test the alarm, please follow the guidelines given on page
Never operate a vehicle in a closed garage, as high levels of CO can be built up in a short time. With an attached garage, dan- gerous CO levels develop inside the home as well as within the garage.
Attempting to test the sensor function by holding the alarm next to a tailpipe or furnace vent may not cause a reading on the dis- play because today’s vehicles emit very little CO once the engine reaches operating temperature. Likewise, many of today’s high efficiency furnaces emit very low levels of CO.