Williams 2001621, Installation & Operating Instruction Manual

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Troubleshooting
Symptom Possible Causes Corrective Action
7. Main burner will not stay on. A. Blockage in vent pipe. Checks vent pipe for blockage, such as bird
nests, twigs, leaves, etc.
Check that the vent cap is properly installed,
and not placed to far down on the vent pipe.
Cap must be the same manufacturer as the
vent.
B. Vent to short. The vent should terminate a minimum of 12 feet
above floor plate. The top of the vent must be
at least 2 feet above any obstacle within a 10
foot radius, including the roof.
C. Restriction in vent system caused by offsets. All type "B" vents shall extend in a vertical
direction with offsets not exceeding 45 degrees.
Any angle greater than 45 degrees from vertical
is considered horizontal. Any offsets used
should be as far above the drafthood as
possible to allow venting to begin before any
restriction is encountered. The use of too many
offsets may also prevent proper venting.
D. Incorrect vent pipe. Use listed B/W type vent pipe. DO NOT use
transite or any other type of ceramic pipe for
venting. DO NOT use single wall pipe. When
venting into a masonry chimney, the chimney
must be properly lined and sized for this gas
furnace. The use of type "B" or flexible chimney
liner is recommended.
E. Loose connections on the vent safety wiring
harness.
Check the connection on both the switch and
the gas valve. Tighten if necessary.
8. Abnormal operation. A. Delayed ignition - pilot flame may be too low. Adjust pilot flame. Refer to "How to Care for
Your Heater" section in this manual.
B. Expansion noise, ticking. Heater may be distorted by being vented
through an uneven opening. A restricted vent
may create expansion noise. Refer to "Venting"
section of this manual.
C. Combustible gas spillage. Check vent system for a blocked flue, excessive
down draft (wind) or negative pressure in room
caused by ventilating fan or a fire in a fireplace.
D. Excessive flame roll-out. Furnace is possibly overrated - check for high
gas pressure at gas valve (see 4B).
E. Burner is over-fired. Check the manifold gas pressure. Check the
rate, this appliance is manufactured for
elevations up to 4,500 feet. It must be derated
for operation above 4,500 feet.
F. Yellow burner flame. Check burner for obstructions. Install new
burner and pilot orifices.
G. Yellow pilot flame. Remove pilot orifice, check and clean.
9. Noisy blower. A. Housing rattling. Tighten blower screws.
B. Blower dirty. Clean blower wheel.
C. Blower wheel bent. Straighten or replace.
10. Blower does not run. A. Fan switch not set. Select fan speed.
B. Check bearings. Add oil as outlined in "Blower Accessory
Instructions".
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