For indoor cold and hot water supply installations, as follows: – Class 1 (hot water 60°C) – design temperature related to service life: 60°C/49 years + 80°C/1 year + 95°C/100 hours. – Class 2 (hot water 70°C) – design temperature related to service life: 70°C/49 years + 80°C/1 year + 95°C/100 hours. INSTALLATION For PP-R pipes that are not installed embedded in a protective sleeve (where expansions occur within the sleeve) and for large-diameter pipes, measures to compensate for expansion must be taken from the design stage. PPR pipes have the expansion coefficient: – PP-R (alpha) = 0.15 mm/m·K, – PP-R/FIBRa (alpha) = 0.088 mm/m·K – PP-R/Al (alpha) = 0.03 mm/m·K. For surface-mounted installation, the system must be secured to prevent uncontrolled pipe movement. Linear expansion is compensated between two fixed points. The system’s fixed points are positioned near branches, valves, or wall penetrations. Fixed points are placed so that expansion forces Length variation of the pipe depending on pipe length and temperature variation is calculated using the following formula: (delta)L = (alpha) x (delta)T x L (delta)L = L-Lo (delta)T = T – To where: (delta)L = total pipe length variation [mm] (delta)T = total temperature variation (alpha) = linear expansion coefficient, [mm/m·K] T = operating temperature To = installation temperature L = pipe length at temperature T, [m] Lo = pipe length at temperature To, [m] Sliding points must be well secured to ensure system alignment, support, and axial movement, preventing vibrations and noise transmission. Calculation of the length of the L-type expansion compensator Where Lb = length of the expansion arm, [mm] d = pipe outside diameter, [mm] (delta)L = total pipe length variation [mm] C = dimensionless material constant (C = 30 for PP-R) PF: fixed point. PM: sliding point Calculation of the U expansion compensator The U compensator is an assembly of 2 L-type compensators, whose length is calculated with the formula above and the minimum width as follows: Lc = 2 x (delta)L + ms, Lc minimum compensator width. ms – safety width = 150 mm