Summer Instrument Maintenance: Why High Temperature Can Be Just as Dangerous as Freezing Weather
When summer arrives, people feel the heat — but industrial instruments often suffer even more.
Under continuous sunlight exposure, high ambient temperatures, and frequent thunderstorms, many instrumentation problems that rarely appear in winter can suddenly emerge during the hot season.
Many instrumentation engineers have the same experience:
In winter, everyone pays close attention to freeze protection, heat tracing, and preventing impulse lines from blocking. However, when summer comes, people often assume that equipment should operate more reliably because there is no freezing risk.
But is that really true?
The answer is no.
High temperatures can create hidden risks for field instruments, control systems, and electrical equipment. If these problems are not identified early, they may eventually affect process stability and even cause unplanned shutdowns.
This article discusses several key areas that instrumentation professionals should focus on during hot weather conditions.
1. Control System Cooling: The First Priority During Summer
The temperature inside control rooms and system cabinets should always be a top priority during summer inspections.
Many engineers believe that a control room equipped with air conditioning is automatically safe. However, during extreme heat periods, air conditioning systems often operate under heavy loads, increasing the risk of overheating.
During routine inspections, engineers should pay special attention to:
- Air conditioning system operating status
- Control room ambient temperature
- Cabinet cooling fans
- Ventilation performance
- Abnormal temperature alarms
A proper inspection record system is also important. Cabinet inspection checklists, temperature records, and maintenance signatures can help ensure that every inspection is completed properly.
For critical cabinets, regular infrared thermal imaging inspections are recommended to identify abnormal heating points before failures occur.
A Real Field Example
During a summer operation period, a control room in an asphalt production facility experienced a sudden equipment failure.
The control room was equipped with only one air conditioning unit. Due to high temperature conditions, the SIS cabinet CPU generated a high-temperature alarm, creating a potential risk of process shutdown.
The maintenance team temporarily installed additional fans to reduce the temperature and stabilize the system.
After the incident, the company conducted a complete review and identified all control rooms with single air-conditioning systems. Backup cooling solutions were added to eliminate this single-point failure risk.
2. Field PLC Cabinets and Analyzer Shelters Also Require Attention
Control equipment installed outdoors or in semi-outdoor environments faces direct exposure to sunlight and high temperatures.
During summer inspections, engineers should check:
- PLC cabinet cooling fans
- Analyzer shelter ventilation systems
- Cabinet internal temperature
- Sun protection measures
- Weather protection conditions
Continuous solar radiation can significantly increase equipment temperature and accelerate aging of electronic components.
Installing proper sunshades or protective covers can effectively reduce thermal stress and extend equipment service life.
3. Hydraulic Cabinets of Special Valves Should Not Be Ignored
In many industrial plants, special control valves use hydraulic systems.
During hot weather, hydraulic oil temperature can rise significantly. Excessive oil temperature may affect system stability and lead to:
- Hydraulic pressure fluctuations
- Slow valve response
- Abnormal valve operation
Therefore, hydraulic cabinets should be included as key inspection points during summer maintenance.
Regular temperature monitoring and cooling system checks can help prevent unexpected valve failures.
4. Solenoid Valve Coil Overheating Risks
Small components are often overlooked, but they can become major failure points.
Solenoid valves installed in high-temperature environments require special attention during summer.
Continuous energization combined with high ambient temperature may cause:
- Coil overheating
- Insulation aging
- Electrical short circuits
- Valve malfunction
For critical solenoid valves, increasing infrared temperature inspection frequency is recommended.
Early detection of abnormal temperature rise can prevent unexpected equipment failures.
5. Outdoor Instruments on Towers and Tanks Need Additional Protection
Instrumentation installed on tower tops, tank roofs, and other elevated locations is directly exposed to:
- Strong sunlight
- Rainwater
- Temperature fluctuations
Many outdoor instrument failures are caused by the combined effects of heat aging and moisture penetration.
For these applications, additional protection measures are recommended:
- Install sunshades
- Add weather protection covers
- Improve cable entry sealing
- Check enclosure protection ratings
These simple improvements can significantly improve instrument reliability in harsh outdoor environments.
6. Mechanical Equipment Can Also Be Affected by High Temperature
Summer heat does not only affect electronic equipment. Mechanical structures can also experience problems.
For example, truck scales and similar weighing systems may experience thermal expansion.
If mechanical clearances remain unchanged from winter or normal-temperature conditions, thermal expansion may reduce gaps and potentially cause:
- Mechanical interference
- Movement restrictions
- Measurement errors
Therefore, mechanical clearance checks should be included in summer maintenance schedules.
7. Check Safety Valves and Fire Protection Devices Carefully
Some safety-related valves and actuators are equipped with temperature-sensitive protection components.
During periods of extreme heat, engineers should verify that these components are suitable for the maximum expected ambient and radiant temperature conditions.
Regular inspection should include:
- Safety device condition
- Temperature rating verification
- Abnormal deformation or damage
- Proper operating status
Preventive inspection helps avoid unintended operation or loss of protection function.
Summer Instrumentation Maintenance Checklist
Before and during high-temperature seasons, instrumentation teams should focus on:
✅ Control room air conditioning and backup cooling
✅ PLC cabinet and analyzer shelter temperature monitoring
✅ Infrared thermal inspections
✅ Hydraulic system temperature checks
✅ Solenoid valve coil temperature monitoring
✅ Outdoor instrument sun and rain protection
✅ Mechanical clearance inspection
✅ Safety device verification
Preventive Maintenance Is the Key to Summer Reliability
Unlike sudden failures, many high-temperature problems develop gradually.
Long-term heat exposure can lead to:
- Electronic component aging
- Reduced insulation performance
- Signal instability
- Mechanical deformation
- Reduced equipment reliability
The best approach is not waiting for failures to happen, but identifying risks before they affect production.
Before summer arrives:
- Complete air conditioning maintenance
- Check cooling systems
- Review vulnerable equipment
- Install necessary sun protection
During hot weather:
- Perform regular inspections
- Use infrared temperature monitoring
- Verify backup systems
- Record abnormal temperature trends
Winter freeze protection is important, but summer heat protection is equally critical.
For industrial plants, reliable operation depends on treating high-temperature instrumentation risks as a regular part of preventive maintenance.