Seasonal Maintenance: Autumn Transitions for Cooling Towers and Boilers

The days are shorter, the temperatures are dropping (even in Arizona & Texas) and fall is upon us. For water treaters in any part of the country, seasonal change means some cooling towers will either run less frequently or be taken out of service for the cooler months. And boilers are getting ready to perform through the winter. This article is a quick reminder of what you need to do to ensure your customer has a smooth transition.

Cooling Towers

Sensors, sensors, sensors. Conductivity sensors should be checked and cleaned, and of course, look over the plumbing for signs of wear or leaks. Flow switches should be cleaned and checked to be sure they operate properly (this is recommended every month BTW.) Pay special attention to pH and ORP sensors – both have sensitive glass elements that need to be cared for and removed from the system if there is either a risk of the element becoming dried out or if water in the line may freeze. Sure we love to provide replacement sensors, but we love satisfied customers more. Don’t be the guy who is calling in the spring asking what that line is in the glass sensor element…

Consider your biocide program, and how to ensure any water that remains in the system will be protected from biological growth. This can be a risk area for pathogens, so think through how you are protecting your customer from risk when that system is started up again. Don’t forget about any low-flow lines that could get dead-ended or just not flushed as often as during peak operation.

Finally, consider any seasonal changes in makeup water composition. Does this municipality have a history of changing from surface water (reservoirs, rivers, lakes) to well water, or a blend? How can you adjust your program to deal with a significant change in incoming conductivity, hardness, or other components? Would operating by Cycles of Concentration, available on Model 1575e, 3175, or NexSys controllers, give you the peace of mind that these changes would be accounted for in your automation program?

Boilers

Again, pay attention to the conductivity sensor. First things first, pull it out of the system and clean it! Boilers generally are really good at depositing material on the sensor tips that can create problems reading system conductivity. Brush it off!  And (of course) look for evidence of leaks that could cause problems in service. If your chemistry program will introduce amines for corrosion protection, consider using a Lakewood HD sensor – harsh duty to resist the leaking that higher levels of amines can cause. Also look at the physical location of the surface blowdown line, conductivity sensor, blowdown valve, flow restriction, etc. See our blog on how these should be located to prevent steam flash at the sensor -the #1 cause of a technical support call/emergency. Don’t forget about any pH sensors that may be in a condensate application.

Calibration – yes do that. In particular, if your location does a lot of calibrations, please initialize the calibration on the controller. Basically, this procedure clears out a lot of old data from the controller’s memory, and it gives you a factory-fresh approach to calibration. If a system has been calibrated frequently or to account for large conductivity differences in the past, there can be some electronic detritus that will cause you problems moving forward. We’re happy to talk you through it at 800-228-0839 – and this procedure takes about 30 seconds.

Check any water meters for proper operation, wiring to the controller, and evidence of shorts in the wiring. Likewise, check the operation of any motorized ball valves: are the actuators moving correctly, and is the valve itself opening and closing properly? Finally, should you expect any debris to be in the system from a boiler that was laid up for the hot months? Be sure the lines are flushed out well so that your sensors, meters, and valves will perform just the way you want them to!