Heating systems depend on accurate and reliable controls to regulate temperature, protect against overheating, and maintain safe operation. Senasys designs and manufactures furnace thermostat and safety switches for OEMs and service applications across residential, commercial, and industrial markets.
Read below to see how Senasys solutions are used in furnaces and wall heating systems.
Snap Disc Switches for Furnaces
In forced-air furnaces, high-limit safety switches are critical to preventing overheating inside the plenum. The Senasys 2511L002-707 snap disc switch provides an automatic reset function that cycles power to the heating elements when temperatures exceed safe limits.
This model handles 25 amps at 240 VAC and is tested for 100,000 cycles, offering a durable mechanical solution without the need for complex electronics. Customizable temperature ratings allow OEMs to specify limits that align with their furnace design.
Key Benefits:
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Automatic reset for safe, unattended operation
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Simple, mechanical design reduces service calls
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Custom calibration available for OEM specifications
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Made in the USA for fast lead times and quality assurance
Find out more about snap disc switches for furnaces ➝
Line Voltage Thermostats for Furnaces
Electric furnaces and cabinet heaters require direct switching of heating elements without additional relays or transformers. Tempro line voltage thermostats from Senasys provide precise control while simplifying installation and wiring.
Available in single- and two-stage configurations, Tempro thermostats directly control 120V or 240V systems, reducing failure points and maintenance costs. Options include rugged enclosures, remote bulb sensors, and broad temperature ranges for both comfort and process heating.
Key Features:
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Switches line voltage directly, eliminating extra components
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Double-pole models improve safety on 240V systems
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Designed for dusty, high-vibration, or fluctuating environments
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Adjustable setpoints from -30°F to 120°F
Explore Tempro line voltage thermostats for furnace applications ➝
Remote Bulb and Capillary Switches for Wall Furnaces
For gas-fired wall furnaces that rely on millivolt gas valves, a Stemco remote bulb and capillary switch offers mechanical temperature control without requiring external power. These switches regulate burner operation by sensing air temperature inside the furnace enclosure.
As the sensing bulb heats, pressure in the capillary tube actuates the control switch, shutting off the burner at the setpoint. When the furnace cools, the switch automatically resets to resume heating.
Technical Highlights:
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Setpoint range: 50°F to 200°F standard, custom options available
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Switch differential: 5°F to 15°F depending on configuration
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Mounting options: panel, bracket, or external knob access
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Compatible with standard millivolt gas valves
Stemco bulb and capillary thermostats are engineered for OEM wall furnace integration, with customizable sensing lengths, materials, and mounting options.
From high-limit snap disc switches to precise line voltage thermostats and bulb and capillary switches, Senasys provides a complete range of furnace thermostat and safety switches. Our solutions support OEM designs, improve safety, and ensure consistent heating performance across residential, commercial, and industrial furnace applications.
Contact Senasys to discuss furnace thermostat and safety switch solutions ➝
