Shutting the Tower and Condenser Systems Down

For anyone in charge of a large plant or building, fall means seasonal shut-down; when you shut down the plant cooling towers and bring boilers online. All the tower lay-up chemicals are on site and when shut-down time arrives you are ready.

While it might be tempting to just metaphorically shut out the lights and simply shut off the circulating pumps, you know that’s NOT what you want to do. All your diligent work throughout the summer can be compromised by ignoring the towers’ water treatment in the fall.

Instead, protect all your effort throughout the year and perform your shut-down with as much care as you employed during maintenance.

Final Week

• Reduce the set-point on the tower to the lower end of the set-point range, or even lower, to help remove any high concentrations of minerals.
• Maintain inhibitor levels.
• Flush ends of condensers to remove any material collected in endbells.

Final 48-72 Hours

• Add oxidizing biocide to maximum system levels. Be sure entire system is circulating.
• Add biodispersant to help penetrate any biofilm.
• Consider adding nonoxidizing biocide after system conductivity has stabilized.
• Add lay-up protection such as ChemFilm to passivate system metallurgy.

• Add lay-up protection such as ChemFilm to passivate system metallurgy.
• The best practice is opening condensers and brushing tubes as soon as possible after fall shutdown, leaving them dry and clean.If chillers will be stored wet for any length of time, drain and refill with fresh water, inhibitor and nonoxidizing biocide.Leaving condensers stagnant all winter, waiting for a good time to drain them is inviting problems.

Clean Up All Chemical Feed Equipment

• Remove and clean probes, then store them in storage solution (pH and ORP).
• Remove corrosion coupons and send them to lab for final evaluation.
• Pump water through all chemical pumps
  Replace any old chemical feed tubing that shows signs of age. It is much easier to replace tubing that has been flushed with water while it is off-line, rather than replacing it mid-season after it has failed and caused a mess.
• Isolate any chemical storage.
• Review chemical feed scheme and equipment, identify where new equipment is needed, and budget for the year ahead.

It’s Important to Be Prepared for Boiler Startup

It’s important to be prepared for fall shutdown. For the best experience when spring arrives, always shut down chillers and chemical feed equipment properly. Make and execute a plan to protect all equipment. And, as you shut down for the fall, reflect on what you need to maintain and can improve in the year ahead. Budget and order parts and pieces now, don’t wait until spring to prepare for startup.

Your Chemtex support team can help you plan all your shutdown and startup procedures to the highest standard, to ensure that you won’t encounter any surprises. Please reach out to us with your questions!