This pneumatic room thermostat is a reliable replacement for older T-4000 series models

maintaining the airtight seal required for optimal draft and secondary heat exchanger performance

Non-Fused Design: Streamlines the installation process for systems where separate overcurrent protection is already provided at the main panel

This high-voltage 7mm silicone ignition wire is engineered to withstand the extreme thermal cycling found in residential and commercial water heater and boiler environments

this heavy-duty solenoid coil features an extended 59-inch lead

Siemens Building Technology 257-02030 Valve Assembly 321042-401 This pneumatic room thermostat isThe Siemens Building Technology 257 02030 Valve Assembly is a high precision solution for terminal unit control in hydronic systems. This 2 way normally open pneumatic valve is engineered with a 1 2 inch NPT connection and a robust forged brass body designed to handle water and 50% water glycol solutions. With a 0. 4 Cv equal percentage flow characteristic, it ensures stable modulating control for convectors, fan coil units, and reheat coils. The