Valrom PPR fittings are used for internal hot water, cold water, and heating installations with PPR pipes. The fittings comply with SR EN ISO 15874-3. Dimensions and applications SDR 6 (S 2.5). Pressure resistance according to the application classes defined in SR EN ISO 15874-1 are: SDR6 fittings withstand: at 20°C PN25 bar with c=1.25 or PN20 at c=1.5. Class 1/PN10. Class 2/PN8 and Class 5/PN6. – Class 1 (hot water 60°C) – design temperature reported to service life: 60°C/49 years + 80°C/1 year + 95°C/100 hours. – Class 2 (hot water 70°C) – design temperature reported to service life: 70°C/49 years + 80°C/1 year + 95°C/100 hours. – Class 5 (radiator heating) – design temperature reported to service life: 80°C/10 years + 60°C/25 years + 20°C/14 years + 90°C/1 year + 100°C/100 hours.