Replacement of Degraded Fluid in a Hotel Solar Thermal System
Seville, Spain
“The system resumed stable operation, and we no longer had to constantly adjust the filters and drains. It was a clear improvement for maintenance.”
Problems Identified
- Thermal degradation of the heat transfer fluid due to aging and exposure to high temperatures.
- Decreased heat transfer capacity.
- Residue formation and possible acidification of the fluid.
- More frequent filter cleaning and corrective maintenance.
- Risk of internal corrosion and reduced service life of components.
Our Intervention
- QUIMACER recommended performing a controlled flush, conducting a visual inspection of the fluid, and completely replacing the circuit if degradation was evident.
- It was determined that the problem should not be solved by adding a new product to the degraded fluid, but rather by replacing the heat transfer fluid and protecting the system.
- It was proposed to select a specific fluid for solar thermal systems that offers greater stability and an appropriate corrosion inhibitor package.
- It was recommended to check the glycol concentration, pH, freeze protection, and the absence of residue after cleaning.
- A regular monitoring plan was established to prevent premature degradation in future seasons.
Solution Implemented
- Drain the degraded fluid and pre-clean the circuit to remove debris from the filters and low-lying areas.
- Replace with FLUISOL ECO / FLUISOL XX, selecting the concentration based on the required thermal protection and operating conditions.
- Incorporation of a fluid with greater stability against thermal cycling and corrosion protection.
- Commissioning with complete air purging, pressure control, and circulation verification.
Target parameters: Stable pH, absence of solids, adequate antifreeze protection, and restored heat transfer.
Results and Improvements
Restoration of the system’s thermal efficiency compared to its degraded state.
Reduction in filter fouling and less frequent maintenance interventions.
Improved fluid stability under high-radiation conditions.
Reduced risk of internal corrosion and associated failures.
Greater operational safety for a critical hotel service: DHW production.
| Parameter | Technical Details |
|---|---|
| Sector | Solar thermal / hotel |
| Location | Seville |
| System | Closed-loop solar DHW system |
| Problem | Fluid degraded by temperature |
| QC Products | FLUISOL ECO / FLUISOL XX |
| Recommended monitoring | pH, concentration, residues, pressure |
| Key Improvement | Greater thermal stability and reduced maintenance |
WHY QUIMACER?
- Fluids specifically designed for solar thermal systems.
- Diagnosis focused on the system's service life, not just on product replacement.
- Protection against degradation and corrosion.
- Technical support for setup, cleaning, and commissioning.
