How many safety valves are generally found on miniature boilers?

Miniature boilers are typically designed with a single safety valve. This safety feature is crucial because it protects the boiler from overpressure, ensuring that excess steam or pressure does not build up to dangerous levels. A single safety valve is generally sufficient for these smaller systems, as they have a lower capacity and operate under less demanding conditions than larger industrial boilers.

Using more than one safety valve on miniature boilers is usually unnecessary and could complicate the system. It is essential that the valve is adequately sized and calibrated to relieve pressure effectively within the operational limits of the boiler. Thus, having one well-maintained safety valve is standard practice for miniature boilers, making it the most appropriate answer.