Induced Draft Cooling Towers
Problem | Possible Causes | Corrective Actions | ||
Increase in the leaving water | 1. | Excess water flow; over pumping. | 1. | Adjust to the design flow. |
temperature | 2. | Recirculation of hot discharge air, back into | 2. | Eliminate obstructions which impede air discharge. |
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| the cooling tower air intakes. Obstructed air |
| For proper location of cooling tower(s), see Delta |
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| intakes |
| dwgs. Baffle air discharge, if necessary. |
| 3. | Proximity of other heat source or discharge | 3. | Remove source or relocate tower. |
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| of moist air. | 4. | See water distribution system instructions. |
| 4. | Improper operation of spray system. | ||
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| A. Orifices clogged. |
| A. Flush spray nozzles, clean orifices, clean |
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| B. Actual water flow is lower than design |
| system, install outlet strainer. |
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| sprinkler rating. |
| B. Install properly rated spray nozzles or increase |
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| to design flow. |
| 5. | Clogged fill. | 5. | Clean the fill. |
| 6. | Damaged fill. | 6. | Replace the fill. |
| 7. | Additional heat load on system. | 7. | Contact Delta for possible upgrade or addition of |
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| another cooling tower selected for additional load. |
| 8. | 8. | None required if condition is temporary. Otherwise | |
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| consult Factory for upgrade. |
Drop in the water flow rate. | 1. | Blockage of spray Nozzle orifices. | 1. | Flush spray nozzle. Clean whole system. Install |
Low water flow rate |
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| outlet strainer. |
| 2. | Low water level in sump causing air to be | 2. | Adjust float valves. Be sure the system is flooded |
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| drawn into pump and piping. |
| and balanced. |
| 3. | Improper selection of water circulating | 3. | Replace with proper size pump designed for flow |
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| pump. |
| and head requirements. Check pump “Net positive |
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| suction head.” |
| 4. | Blockage of strainers. | 4. | Backwash or clean. |
| 5. | Pump malfunction. | 5. | Consult pump specialist. |
Noise and vibration | 1. | Loose bolts. | 1. | Recheck and tighten all bolts to specified torque. |
| 2. | Mechanical interference of rotating parts. | 2. | Inspect propeller for free rotation. Check propeller |
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| for mechanical interference. Adjust, repair or |
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| replace, as necessary. |
| 3. | Fan propeller damaged or out of balance. | 3. | Replace components, as necessary and check |
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| balance. Install vibration |
| 4. | Air intake at pump. | 4. | Check basin water level and irregular piping design. |
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| 5. | Match pump NPSH with system hydraulics. |
| 5. | Pump cavitation. | 6. | Check and replace motor. |
| 6. | Damaged motor bearings. |
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Sudden or short term irregularities of | 1. | Peculiarities of specific system and its | 1. | Inspect system and review operation procedures. |
cold water level in basin |
| operation. |
| Correct, as applicable valve settings, loss of water in |
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| system, fill system to flooded capacity. |
Excessively high water level in sump on | 1. Gravity flow restrictions due to insufficient | 1. |
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gravity drain installation |
| head differential. | A. Outlet piping should terminate below sump tank | |
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| water level. |
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| B. Increase discharge pipe size. | |
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| C. | Increase head by mean other than A. |
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