Laars Heating Systems R0011900 Ignition Module 326058 757 Smith 100327113 Thermostat is a Smith 100327113 Thermostat is a critical surface thermostat engineered for high accuracy temperature regulation in commercial and residential water heating systems Industrial Grade Durability: The stainless steel construction ensures long term resistance to corrosion and refrigerant exposure in demanding mechanical rooms this module will continue to cycle the ignition sequence to restore heat without technician intervention this Laars OEM replacement part provides the exact electrical specifications and timing sequences required to maintain safe gas manifold pressures and reliable combustion cycles