Water Quality: Heating Systems & Drinking Water
pH, TDS (PPM) and electrical conductivity (µS/cm) directly affect system durability, efficiency, taste and safety.
Water Quality for Heating Systems
In closed heating systems, water quality is critical. Incorrect values lead to corrosion, scale buildup and reduced heat transfer.
Low pH (< 7.0)
- Strong corrosion
- Rust and sludge formation
- Black system water
- Shortened equipment lifespan
Optimal pH (7.0 – 8.5)
- Chemically stable water
- Minimal corrosion
- Clean and efficient system
High pH (> 9.0)
- Scale and sludge formation
- Dangerous for aluminum heat exchangers
- Reduced heat transfer
TDS (PPM) – Dissolved Solids
Higher TDS means more minerals, increasing scale buildup and operating costs.
| PPM (TDS) | Evaluation | Impact |
|---|---|---|
| < 50 | Ideal | Maximum system protection |
| 50 – 100 | Acceptable | Normal operation |
| 100 – 300 | Risky | Scale and efficiency loss |
| > 300 | Not suitable | Rapid system damage |
Electrical Conductivity (µS/cm)
High conductivity accelerates electrochemical corrosion.
| µS/cm | Evaluation | Risk |
|---|---|---|
| < 100 | Ideal | Long system lifespan |
| 100 – 200 | Acceptable | Low risk |
| 200 – 600 | Risky | Corrosion and deposits |
| > 600 | Not suitable | Frequent failures |
Recommended Heating System Water Values
- pH: 7.0 – 8.5
- TDS (PPM): < 100
- Conductivity: < 200 µS/cm
Properly treated water = lower costs + longer lifespan
Drinking Water Quality
For drinking water, balanced mineral content and correct pH ensure good taste, safety and minimal impact on plumbing.
Low pH (< 6.5)
- Sour or metallic taste
- Corrosive to pipes
- Possible metal leaching
Optimal pH (6.5 – 8.5)
- Clean, neutral taste
- Safe for consumption
- Balanced water chemistry
High pH (> 8.5)
- Bitter or soapy taste
- Increased scale formation
| Parameter | Ideal Range | When Problems Start |
|---|---|---|
| pH | 6.5 – 8.5 | <6.5 or >8.5 – taste and pipe issues |
| TDS (PPM) | 50 – 150 | >300 – hard water, poor taste |
| Conductivity (µS/cm) | 100 – 300 | >600 – high mineral content |
Conclusion
For drinking water, balanced pH and moderate mineral content ensure good taste, safety and fewer household problems.