AIR CAPACITY PROBLEMS:
1. Resistance of system not at design rating. If resistance
is lower than expected, both air flow and horsepower
may be up. If resistance is higher than anticipated, air
volume will be down.
2. Fan speed is not at design speed.
3. Air density not at design values. Also check air
performance measurement techniques/procedures.
4. Devices for air modulation are closed or plugged. Also
check filters.
5. Wheel mounted improperly or is rotating in reverse.
6. Parts of system or fan have been damaged or need
cleaning.
NOISE PROBLEMS:
.
1. Air performance is incorrect and fan is not at design
point of operation. Fan forced to operate in an unstable
flow region.
2. Bearing failure. Check bearings (lubrication).
3. Supply voltage high or inconsistent supply frequency.
Adjustable frequency controllers can generate motor
noise.
4. Objects which are installed in a high velocity airstream
can generate noise. This includes flow sensors, turning
vanes, etc.
5. Poor fan inlet conditions.
6. Acoustics or sound measurement procedure incorrect.
VIBRATION PROBLEMS:
1. Misalignment of drive components.
2. Poor foundation or mounting structure (resonances).
3. Foreign material attached to rotating components.
4. Damaged rotating components (bearings, shaft, fan,
wheel, sheaves.)
5. Broken, loose or missing set screws.
6. Loose bolts.
7. Vibration transmitted by another source.
8. Water accumulating in airfoil blades.
9. Fan is operating in stall or unstable flow region.
MOTOR PROBLEMS:
1. Incorrect wiring.
2. Speed of fan too high.
3. Parts improperly installed - binding.
4. Bearings improperly lubricated.
5. WR2 capability of motor too low for application.
6. Protection devices may be improperly sized.
DRIVE PROBLEMS:
1. Belts improperly tensioned.
2. Drive alignment is poor.
LIMITATION OF WARRANTIES and CLAIMS
Seller warrants to the original purchaser that the goods
sold hereunder shall be free from defects in workmanship
and material under normal use and service (except in
those cases where the materials are supplied by the
buyer) for a period of one year from the date of original
installation or eighteen (18) months from the date of ship-
ment, whichever occurs first. The liability of seller under
this warranty is limited to replacing, repairing, or issuing
credit (at cost, F.O.B. factory and at seller's discretion) for
any part or parts which are returned by buyer during such
period provided that (a) seller is notified in writing within
ten (10) days following discovery of such defects by
buyer, or within ten (10) days after such defects should
reasonably have been discovered, whichever is less; (b)
the defective unit is returned to seller, transportation
charges prepaid by buyer; (c) payment in full has been
received by seller for said products; and (d) sellers exami-
nation of such unit shall disclose to its satisfaction that
such defects have not been caused by misuse, neglect,
improper installation, repair, alteration, act of God, or acci-
dent. No warranty made hereunder shall extend to any
seller product whose serial number is altered, effaced or
removed. Seller makes no warranty, express or implied,
with respect to motors, switches, controls, or other compo-
nents of seller's product, where such components are war-
ranted separately by their respective manufacturers. THIS
WARRANTY IS EXPRESSLY IN LIEU OF ALL OTHER
WARRANTIES, EXPRESS OR IMPLIED, WHETHER
STATUTORY OR OTHERWISE, INCLUDING ANY
IMPLIED WARRANTY OF MERCHANTABILITY OR FIT-
NESS FOR A PARTICULAR PURPOSE. In no event shall
seller be liable to buyer for indirect, incidental collateral, or
consequential damages of any kind. (BUYER'S FAILURE
TO PAY THE FULL AMOUNT DUE WITHIN SIXTY (60)
DAYS OF DATE OF lNVOICE SHALL OPERATE TO
RELEASE SELLER FROM ANY AND ALL LIABILITY OR
OBLIGATION ARISING PURSUANT TO ANY WARRANTY
EXPRESS OR IMPLIED, WHETHER STATUTORY OR
OTHERWISE, INCLUDING ANY IMPLIED WARRANTY
OF MERCHANTABILITY OR FITNESS FOR A PARTICU-
LAR PURPOSE, MADE IN CONNECTION WITH ANY
CONTRACT FORMED HEREUNDER. BUYER AGREES
THAT SUCH FAILURE TO PAY SHALL CONSTlTUTE A
VOLUNTARY WAIVER OF ANY AND ALL SUCH WAR-
RANTIES ARISING PURSUANT TO SUCH CONTACT.)
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