In the practical process of upgrading and renovating heat exchange stations, users may sometimes have misconceptions or make flawed decisions that result in project delays or unsatisfactory outcomes. Henan Rentai has summarized five common pitfalls in the industry and provided professional suggestions for each, helping heating companies, system integrators, and engineers avoid these traps and successfully advance heat exchange station automation renovations.
Pitfall 1: Focusing only on control equipment while neglecting signal acquisition accuracy
Many users focus solely on upgrading the PLC or controller but overlook the accuracy and reliability of field sensors and instruments. In older heat exchange stations, temperature and pressure sensors are often uncalibrated or degraded, resulting in large data errors. If these are not replaced or recalibrated, even the most advanced control systems will be making decisions based on “garbage data,” leading to poor control performance.
Solution:
Pay attention to the measurement layer. Upgrade key sensors and instruments when necessary to achieve high-precision data acquisition and visualization. For example, install high-accuracy temperature and pressure transmitters on the primary and secondary pipelines, replacing outdated analog gauges. Henan Rentai emphasizes the importance of “sensory organs” in its renovation plans, enhancing temperature, flow, and level monitoring to make previously ambiguous parameters transparent and provide a solid foundation for optimized control. Accurate signal acquisition is the prerequisite for effective automatic control.
Pitfall 2: Upgrading only the control unit without updating related sensors, valves, and actuators
Some projects aim to cut costs by upgrading only the PLC or industrial computer, while field actuators (like control valves and pump drivers) remain manual or outdated. This mismatch between new and old equipment prevents automation from being fully implemented. For example, the PLC may calculate a desired flow adjustment, but a manual valve cannot respond; or it may want to adjust pump speed, but the pump lacks a variable frequency drive (VFD), so it always runs at full speed.
Solution:
Adopt a system-level upgrade approach. Upgrade key actuators and communication interfaces together. For example, replace manual valves with electric control valves or equip them with actuators to allow remote PLC control. Install VFDs for constant-speed pumps to enable load-based speed regulation. Also, ensure compatibility between the new PLC and existing device signal types, such as matching analog ranges and ensuring signal isolation. Use signal converters or intermediate relays where needed. In short, avoid isolated upgrades. Instead, optimize the full control loop—sensing, processing, and actuation—for maximum efficiency.
Pitfall 3: Underestimating project workload, leading to poor scheduling and resource allocation
Some users think heat exchange station automation renovation is just a matter of swapping a cabinet or installing a PLC, expecting it to be completed in a day or two. In reality, it involves on-site surveys, system design, dismantling, installation, wiring, and debugging. When constrained by the heating season, meticulous scheduling is essential. Without sufficient preparation or resource allocation, project delays are likely, even missing critical heating deadlines.
Solution:
Develop a detailed project plan and coordination mechanism. Schedule work during non-heating periods or low-demand times, leaving adequate buffer time. Create a construction timeline that breaks tasks into stages (e.g., dismantling, installation, wiring, single-machine testing, system integration), with clear deadlines and contingency plans. Coordinate all disciplines—civil, electrical, and commissioning—and ensure timely delivery of equipment and materials. During execution, project managers should monitor progress and address bottlenecks quickly. If technical issues delay progress, communicate with heating dispatch departments promptly and consider temporarily continuing with the old system. Scientific project management helps avoid delays caused by over-optimism or under-preparation.
Pitfall 4: Overlooking the importance of system commissioning
Some believe that once installation is complete and the program is downloaded, the system will run smoothly. This is a dangerous misconception. Without thorough debugging and parameter tuning, a newly installed system may suffer performance issues or even pose safety risks. Problems like improper PID tuning can cause large temperature fluctuations; flawed logic may lead to frequent pump cycling or valve oscillation; poorly set alarm thresholds can result in nuisance alerts.
Solution:
Allocate sufficient time and skilled personnel for thorough system commissioning. Before go-live, test the program in a simulation or offline environment to identify errors. Once operational, have experienced engineers monitor the system onsite to optimize parameters. For instance, analyze temperature trends and adjust PID values as needed, or reduce pump cycling by fine-tuning logic. Carefully test all alarms to confirm their triggers and eliminate unnecessary ones. This detailed tuning process ensures the system meets performance expectations. Never rush or skip commissioning—it is the “polishing” phase that ensures long-term stability.
Pitfall 5: Reusing aged components and leaving hidden risks in the system
To save costs, some projects choose not to replace long-used electrical components such as circuit breakers, terminals, or cables. However, after years of operation, insulation degrades and contacts wear out, severely compromising reliability. These aging components may become weak links, leading to faults like short circuits, tripping, or even shutdowns—completely defeating the purpose of the upgrade.
Solution:
Replace all critical electrical components without hesitation. Before renovation, inspect all components in the control cabinet. Replace any parts showing signs of aging or underperformance. For example, measure insulation resistance of busbars and wiring—anything below safety thresholds must be replaced. Check switches and contactors for smooth operation and burnt contacts, and upgrade them if needed. Use new components with built-in protection features, such as leakage-protection breakers and thermal-magnetic motor protectors, to enhance system safety. Investing in new, reliable components eliminates hidden risks and ensures stable long-term operation. Don’t let outdated parts ruin a new system.
These five pitfalls are common in heat exchange station automation upgrades—but fortunately, they can all be avoided with foresight and professional planning. Heating companies and project teams should examine each decision with a holistic perspective—considering not only the PLC upgrade but also the sensors and actuators; not just cost efficiency, but also quality and safety. Experienced service providers like Henan Rentai will proactively identify and help avoid these pitfalls from the early stages of the project, ensuring a successful outcome.
A properly executed renovation can significantly improve control precision and energy efficiency. Henan Rentai Electric Equipment Co., Ltd. has rich experience and strong technical capabilities in heat exchange station automation renovation. We offer customized PLC + HMI integrated solutions and full-cycle professional services to ensure a safe and efficient upgrade process—revitalizing outdated heat exchange stations for the modern era.
For more information, please contact Henan Rentai Electric Equipment Co., Ltd.
Phone: +86 17638563962 / 0371-56520104 Email: info@hnrentai.com