Troubleshooting guide

TB-A028-06 - A. O. SMITH - FVIR INTELLI-VENT TROUBLESHOOTING CHART
A. O. Smith Water Products Company AHSTB02807 Technical Training Department
Ashland City, Tennessee © 2006 5 of 5 Intelli-Vent Trouble Chart FVIR AOS.fm
Additional Recommended Service Publications
• Power-Vent service manual - part number TC-048 R6 (revision 6 or later)
• Intelli-Vent™ service manual supplement - part number GTC-070 R3 (revision 3 or later)
• Air Pressure Switches technical bulletin - number TB-A023-06
Visit our web site at www.hotwater.com to download the above service manual and supplement.
Revision numbers for these service publications are designated by R3, R4, R6, R7, etc. as a suffix
to the part numbers IE: GTC-070 R4
# LED STATUS PROBLEM SOLUTION
16
LDO (Lint, Dust, and Oil) lock-
out condition.
Air pressure switch circuit is
opening repeatedly during one
heating cycle. May be caused by
the air pressure switch and/or
the vent temperature limit switch
(these two switches are wired
together in a “series” circuit).
1 Check/clean intake air screen on the base ring of the
water heater.
2 Check/clean the dilution air screen on the blower
assembly.
3 Check/clean the flame arrestor - see the service note
below.
4 Remove the blower assembly and check the flue
baffle - ensure the flue baffle is in good condition and
properly installed - reinstall as necessary and/or
replace the flue baffle if worn or damaged.
5 Ensure water heater is not over-firing - check burner
orifice size - ensure the correct orifice is installed -
replace as necessary.
6 Ensure water heater is not over-firing - check
manifold gas pressure - ensure manifold gas
pressure is within 0.3” W.C. of the listed rating on the
Intelli-Vent™ control valve. Manifold gas pressure is
non-adjustable, if manifold gas pressure is off by
more than 0.3” W.C. - replace the Intelli-Vent™
control.
7 Check the vent temperature limit switch - if it is
determined that the vent temperature limit switch is
opening its contacts at normal operating
temperatures during the heating cycle - replace the
vent temperature limit switch.
Service Note: the flame arrestor is accessible
through the intake air opening in the base ring of the
water heater with the intake air screen removed. Use
a non-metallic household brush to clear away any lint
or dust from the ceramic flame arrestor, then vacuum
the surface of the flame arrestor and the base ring air
chamber thoroughly with a household vacuum
cleaner. A suitable vacuum hose attachment can be
fabricated in the field using a short length of 1/2”
PVC pipe with a short radius elbow on one end. Use
tape to temporarily seal it to the vacuum hose.