_O & M MANUAL - WEST LANE MOBILE HOME PARK

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OPERATION Before operating a blower under power for the first time, recheck the unit and the installation thoroughly to reduce the likelihood of avoidable troubles. Use the following procedure check list as a guide, but consider any other special conditions in the installation. ❑ Be certain that no bolts, tools, rags, or debris have been left in the blower air chamber or piping. ❑ If an outdoor intake without filter is used, be sure the opening is located so it cannot pick up dirt and is protected by a strong screen or grille. Use of the temporary protective screen as described under INSTALLATION is strongly recommended. ❑ Recheck blower leveling, drive alignment and tightness of all mounting bolts if installation is not recent. If belt drive is used, adjust belt tension correctly. ❑ Turn drive shaft by hand to make sure impellers still rotate without bumping or rubbing at any point. ❑ Make sure oil levels in the main oil sumps are correct. ❑ Check lubrication of driver. If it is an electric motor, be sure that power is available and that electrical overload devices are installed and workable. ❑ Open the manual unloading valve in the discharge air line. If a valve is in the inlet piping, be sure it is open. ❑ Bump blower a few revolutions with driver to check that direction of rotation agrees with arrow near blower shaft, and that both coast freely to a stop. After the preceding points are cleared, blower is ready for trial operation under "no-load" conditions The following procedure is suggested to cover this initial operation test period. a. Start blower, let it accelerate to full speed, then shut off. Listen for knocking sounds, both with power on and as speed slows down. b. Repeat above, but let blower run 2 or 3 minutes. Check for noises, such as knocking sounds. c. Operate blower for about 10 minutes unloaded. Check oil levels. Observe cylinder and headplate surfaces for development of hot spots such as burned paint, indicating impeller rubs. Be aware of any noticeable increase in vibration. Assuming that all trials have been satisfactory, or that necessary corrections have been made, the blower should now have a final check run of at least one hour under normal operating conditions. After blower is restarted, gradually close the discharge unloading valve to apply working pressure. At this point it is recommended that a good pressure gauge or manometer be connected into the discharge line if not already provided, and that thermometers be in both inlet and discharge lines. Readings from these instruments will show whether pressure or temperature ratings of the blower are being exceeded. During the final run, check operating conditions frequently and observe the oil levels at reasonable intervals. If excessive noise or local heating develops, shut down immediately and determine the cause. If either pressure rise or temperature rise across the blower exceeds the limit specified in this manual, shut down and investigate conditions in the piping system. Refer to the TROUBLESHOOTING CHECKLIST for suggestions on various problems that may appear. The blower should now be ready for continuous duty operation at full load. During the first few days make periodic checks to determine whether all conditions remain steady, or at least acceptable. This may be particularly important if the blower is supplying air to a process system where conditions can vary. At the first opportunity, stop the blower and clean the temporary inlet protective screen. If no appreciable amount of debris has collected, the screen may be removed. See comments under INSTALLATION. At this same time, verify leveling, coupling alignment or belt tension, and mounting bolt tightness. Should operating experience prove that blower capacity is a little too high for the actual air requirements, a small excess may be blown off continuously through the manual unloading or vent valve. Never rely on the pressure relief valve as an automatic vent. Such use may cause the discharge pressure to become excessive, and can also result in failure of the valve itself. If blower capacity appears to be too low, refer to the TROUBLESHOOTING CHECKLIST. Vibration Assessment Criteria With measurements taken at the bearing locations on the housings, see chart below for an appropriate assessment guide for rotary lobe blowers rigidly mounted on stiff foundations. In general, blower vibration levels should be monitored on a regular basis and the vibration trend observed for progressive or sudden change in level. If such a change occurs, the cause should be determined through spectral analysis. As shown on the chart below, the level of all pass vibration will determine the need to measure discrete frequency vibration levels and the action required. All Pass Vibration (in/sec) Discrete Frequency Vibration (in/sec) Action 0.45 or less N/R Approved Greater than 0.45 0.45 or less @ Approved but 1.0 or less any frequency Greater than 0.45 @ ROOTS" Approval any frequency Required Greater than 1.0 Less than 1.0 ROOTS" Approval Required Greater than 1.0 ROOTS'" Approval Required ©2002 Dresser, Inc all rights reserved. ROOTS. RAM, URAI and NMISPAIR are trademarks of Dresser, Inc.