The M30 is a basic mechanical heat-only thermostat designed for 24-volt (low voltage) and millivolt heating systems. It provides simple, reliable temperature control using a manual lever or dial, making it ideal for straightforward heating setups.

It’s commonly used with single-stage furnaces, boilers, and other heat-only systems, and is popular for homes, RVs, and mobile housing due to its easy installation and no-frills operation.

• Works with 24V and millivolt heating systems
• Designed for heat-only (no cooling) applications
• Mechanical control (no programming or batteries needed)