Safety valve 8115 4 bar 1/2 inch, solar 8115.15.152

Solar system overpressure protection

Membrane safety valve 8115.15.152 opens at a pressure of 4 bar, making it suitable for medium‑power solar installations – e.g., with collectors up to 50 m². It acts as the last line of defence, stopping the exceedance of the allowable pressure in the liquid circuit, which prevents damage to pipes, fittings or the collector itself.

The working medium is water with glycol added – up to 50 % – which makes it compatible with most heating systems in low‑temperature regions. It does not operate on steam or aggressive gases, but for liquids in solar systems it is sufficiently resistant.

For the installer – simplicity and precision

The valve has a 1/2" thread, corresponding to DN15 – a standard size in domestic and medium‑size installations. The 4 bar setpoint is intentional: it is chosen for the typical operating range of flat and tubular collectors, where pressure can rise after overheating when flow stops. This value prevents frequent dripping during normal operation while reacting quickly to pump failure or flow blockage.

Operating temperature up to 160 °C means the valve can withstand even short‑term overheating – e.g., on a bright day with no heat demand. It does not need to be replaced after each overheating cycle, as the membrane does not degrade under such conditions.

For the user – no unnecessary failures

You do not have to worry about sudden pressure spikes on a hot day. The valve works without electricity or electronics – purely mechanically. If something fails in the pump or controller, this element will activate itself and discharge excess energy through the drain. It requires no maintenance, has no filters to clean. Its sole function is safety – and it performs it effectively.