Inaccessible access holes
Some of the connections were relatively straightforward. For instance, each of the ice system manifolds were served by a single-braided hose with no branch connections, as the feedlines ascended up and through the structure. On the other hand, the fog and rain systems were a different story, as each has several branches from the feedline to the individual manifold branches. To put this into perspective, the high pressure fog system has 24 branches.
As the feedlines branch away from the vertical columns, the plumbing was fed through small access holes, which were limited in size due to structural requirements. If they were made too big, the structure would not be able to withstand the lateral forces of the wind, not to mention other loads. The location of the access holes were also critical, as each one had to be positioned well back from the structural steel’s vertical-to-horizontal connections to ensure the integrity of the structure was not compromised.
This made Acapulco Pools’ job of connecting the horizontal plumbing branches to the vertical feedlines quite difficult, as it was impossible to reach the connection point by hand. Therefore, to manage this, Atomizing Systems developed special, quick-release tools designed specifically for use on the structure. However, before these tools could be developed, Acapulco Pools shipped a mock-up of the structural interface to Atomizing Systems’ offices in New Jersey with the proposed access holes in place to assist in manufacturing the tools.
Once they were developed, Acapulco Pools’ technicians were able to make the final branch connections to the main feedlines. If a leak were to occur after the structure was erected, it would be disastrous. Finding the problematic fitting among dozens of other connections that are all wrapped with heat tracing and encased in insulation would be impossible. As a result, the entire feedline would need to be removed to repair a leak.
Therefore, to reduce the likelihood of a leak after installation, the entire feedline for each system—and all of its branches—were pre-assembled and pressure tested at 6895 kPa (1000 psi) at Acapulco Pools’ project support centre before the Weather Catcher was installed.
It was also important the preassembly accounted for the physical orientation of each and every fitting. The lengths of heat tracing required for each horizontal branch also had to be predetermined and installed as part of the preassembly to avoid an excessive number of electrical splices in the heat trace. Every splice is a potential electrical failure and an opportunity for water to enter the watertight splice connection.
Water quality
The quality of the water used by the Weather Catcher was also critical. That said, water with low-mineral content (total dissolved solids [TDS]) is required so there is no build-up in the small, non-wearing ruby-orifice fog nozzles. Given the sensitivity of the nozzles, it was important to maintain nearly hospital-clean conditions during the assembly to prevent any contamination from entering the plumbing. Further, any minerals in the water would also need to be removed to prevent the formation of unsightly scale or rust on the structure. To manage this, DEW specified a water treatment system that included a commercial quality water-softening system, reverse osmosis (RO) filter, ultraviolet light (UV) sanitizer, along with a holding/buffer tank system. A booster pump was also included as part of the water treatment system to provide the appropriate water volume and pressure to serve all three systems.
When the feature is not operating, or when only a portion of the available treated water is required, a pressure relief valve returns the excess water to the holding tank where it is continuously recirculated, treated, and ready for use by the next feature cycle.
Weather permitting
It was clear there would be certain weather conditions when it would be inappropriate to operate the Weather Catcher’s systems. For instance, if wind speeds are quite high, or when it is extremely cold, it may not be appropriate to run any of the systems that day. However, when wind speeds are more moderate, it might be good to run lower levels of rain, and exclude the high levels. Similarly, when the temperature drops toward zero, the rain feature must not be operated, but the ice system should run.
The Weather Catcher is able to automate the operation of the three features thanks to a weather station installed discretely at the top of the structure. It collects and sends current weather information to an automation system, programmed by Atomizing Systems, to interpret and control the three systems according to fixed and adjustable parameters that were designed into the automation software.
Operators are also able to turn the Weather Catcher’s systems on/off at certain times of day, depending on variables such as wind speeds and directions, etc. Some parameters, however, are fixed to protect the system. For instance, if it is -40 C, an operator cannot override the system to turn it on. The programming parameters, set points, and current status of the system are all accessed through a touch screen human-machine interface (HMI) installed in an ergonomically sound way in the equipment room. The automation system also generates alarms if something is wrong (e.g. low water pressure from the water treatment system).
