Unexpected issues arising with boilers can cause significant disruptions to a plant’s operations, leading to unplanned downtime. Facilities who have wisely chosen to implement robust boiler upgrade and maintenance programs have witnessed improvements in their overall process uptime.

In many cases, boiler system upgrades consist of replacing mechanical switches and gauges with advanced electronic instrumentation (e.g., transmitters). However, these upgrades often come with hefty price tags, and sometimes a costly smart transmitter can be an overkill for a simple boiler pressure or temperature control application. Users are simply looking for affordable instrumentation that gets the job done and is simple to install, maintain and operate. This ‘technology gap’ has resulted in the demand for an emerging class of affordable instrumentation called electronic switches.

Electronic Switches

Electronic switches (e.g., pressure and temperature) combine the benefits of a mechanical switch (e.g., simplicity) and a smart transmitter (e.g., device diagnostics). Some electronic switches are even designed to operate using the same 2 wires (power and signal cables to PLCs/DCS) as your mechanical instrumentation. This eliminates the need for additional wiring infrastructure, creating an ideal drop-in-upgrade solution. Electronic switches are typically less than half the cost of smart transmitters.

Electronic switches can create a higher level of maintenance efficiency for boiler operators. From a maintenance standpoint, operators can spend up to 12 hours per year per mechanical switch just to calibrate, test and install a switch. If an electronic switch is used instead, this maintenance time can be significantly reduced to 30 minutes per year.

For instance, a critical boiler maintenance practice is the regular upkeep of the boiler fuel system. An efficient fuel system ensures that fuel is not wasted, optimizing fuel costs. Another example is the water treatment system in the boiler which requires routine maintenance, failure which would cause the unnecessary buildup of impurities resulting in boiler inefficiency. In these two examples, older boiler systems are fitted with mechanical switches that can only trigger alarms when the pressure in the fuel system or water filter is abnormal. In addition, there is also no way of confirming onsite if the switch is functioning as intended to be.

When electronic switches are deployed in place of the mechanical instrumentation, the user can now monitor the device and process health data derived from the embedded diagnostics. Alarm and reset levels can also be programmed onsite with precision settings that are four times more accurate than a mechanical switch. Boiler fuel and water treatment systems can now be fine-tuned to an optimal arrangement.

Here is an example of how electronic switches has created maintenance efficiency for a customer who operates several gas-fired boilers in their facility.