Appendix 2 -
Cooling Tower
Mechanical and Water Surveys

1. Does the belt squeal during operation? If so, tighten belts.

2. Check motor amp draw and voltage.

• If voltages are off, check with Virginia Power.
• If too low, check for collapsed fill or blockage.
• If too high, check water distribution header, nozzles, and flow rate of pump in gallons per minute (gpm).

3. Does the tower have excessive vibration? If so, then:

• Check fan wheels for cleanliness. Clean, balance or replace as necessary.
• Check bearings and lubricate.
• Check belt tightness and adjust.
• Realign the shaft.

4. Is the tower free of debris? If not, clean.

5. Clean the sump strainer.

6. Check the integrity of the fill deck and eliminators. (Older towers may contain asbestos components.) Contact the manufacturer if problems are apparent.

7. Check for full flow bypass if one is used.

8. Check for Variable Frequency Drive on the cooling tower water pump.

• A cooling tower will not operate properly on a variable, or varying water supply, unless the reduction in flow is limited to the manufacturer's minimum recommended flow for that cooling tower.
• The fan motors may be operated on a Variable Frequency Drive.

9. Ensure that the cooling tower discharge is not drawn into the building ventilation or make-up air system.

10. Ensure that boiler stacks or steam vents do not discharge into the tower. If they do, then:

• Raise the stack.
• Block airflow from the stack to the tower.

1. Does water overflow during steady-state operation? If so, then:

• Reset sump water level lower.
• Equalize flow in multi-cell installations.

2. At shut-down of fan/pump, does water overflow? If so, then:

• Reset the water level lower.
• Install a check valve in the supply line.

3. Does the tower leak at its seams? If so, then seal according to manufacturer's recommendations.

4. Does the entering water basin at the top of the tower overflow (applicable to crossflow-systems only)? If so, then:

• Check for clogged metering orifices.
• Adjust flows to balance levels in both basins.

5. Does water drip from the fan scroll weep-hole (applicable to centrifugal fan-forced draft systems only)? If so, then:

• Reduce sump water level.
• Run fans whenever the pumps run, using pony motors or capacity control dampers.

6. Does water spray from the top of the tower? If so, then:

• Adjust the eliminators if upside down or skewed, and replace if corroded or broken.
• Check the water flow rate.
• Check fan RPM.
• Check fan pitch (induced-draft systems only).
• Reduce water level.

7. Does the make-up valve leak? If so, then:

• Replace the valve seat or valve.
• Install a pressure-reducing valve set at 25-30 psi.
• Install an electric make-up valve.

8. To what should the overflow and drain lines be connected?

(This will vary at each facility, depending on in-house policy subject to applicable local, state, and federal regulations.)

9. Does the pump leak? If so, replace the seals.

10. Is a conductivity (Total Dissolved Solids - TDS) meter with a purge valve installed?

• Ensure there is no overflow at the tower.
• There is a conductivity TDS meter with a purge valve on most systems. Whether cooling tower water is treated chemically or non-chemically, a conductivity meter will reduce water waste.