First Alert MODEL FCD3N - Manual (Page 16)

15
Potential Sources Of CO In The Home
Fuel-burning appliances like: portable heater,
gas or wood burning fireplace, gas kitchen
range or cooktop, gas clothes dryer.
Damaged or insufficient venting: corroded or
disconnected water heater vent pipe, leaking
chimney pipe or flue, or cracked heat
exchanger, blocked or clogged chimney
opening.
Improper use of appliance/device: operating
a barbecue grill or vehicle in an enclosed area
(like a garage or screened porch).
Transient CO Problems: “transient” or on-
again-off-again CO problems can be caused by
outdoor conditions and other special
circumstances.
The following conditions can result in
transient CO situations:
1. Excessive spillage or reverse venting of fuel
appliances caused by outdoor conditions
such as:
• Wind direction and/or velocity, including
high, gusty winds. Heavy air in the vent
pipes (cold/humid air with extended
periods between cycles).
• Negative pressure differential resulting
from the use of exhaust fans.
• Several appliances running at the same
time competing for limited fresh air.
• Vent pipe connections vibrating loose
from clothes dryers, furnaces, or water
heaters.
• Obstructions in or unconventional vent
pipe designs which can amplify the
above situations.
2. Extended operation of unvented fuel burning
devices (range, oven, fireplace).
3. Temperature inversions, which can trap
exhaust close to the ground.
4. Car idling in an open or closed attached
garage, or near a home.
These conditions are dangerous because they
can trap exhaust in your home. Since these
conditions can come and go, they are also hard
to recreate during a CO investigation.
M06_1042_001.E Page 15 Wednesday, July 12, 2000 9:26 AM