Furnas Controls

Furnas Controls is a manufacturer of motor control equipment including contactors, motor starters, control relays, and contact accessories for HVAC, refrigeration, and industrial electrical applications. Furnas Controls products are now manufactured under the Siemens brand family, with Furnas-designated products continuing to serve the HVAC and industrial replacement market. Furnas contactors are built to NEMA standards for motor control, covering single-pole through multi-pole configurations in both definite purpose and general purpose designs. The Furnas Centurion 2000 definite purpose contactor line covers ratings from 25 to 210 amps, the largest definite purpose motor control line in the industry. Electrical contractors, HVAC technicians, and panel builders specify Furnas Controls where NEMA-rated motor control reliability and broad replacement part availability are the primary requirements.

Furnas Controls Product Lines

Definite Purpose Contactors

Furnas definite purpose contactors are designed for controlling air conditioning, heating, welding, data processing, and refrigeration equipment where a compact, application-specific contactor is required. The Furnas Centurion 2000 is the flagship definite purpose line, offering ratings from 25 to 210 amps and covering the largest range of definite purpose motor control in the industry. Definite purpose contactors from Furnas Controls are available in single-pole, two-pole, and three-pole configurations to match single-phase and three-phase HVAC equipment. Furnas definite purpose contactors are a standard replacement item for compressor and condenser fan motor control in split-system and packaged HVAC equipment. Where a full NEMA-rated general purpose contactor may be oversized for an HVAC compressor application, the Furnas definite purpose contactor provides a right-sized, application-specific solution.

NEMA General Purpose Contactors and Motor Starters

Furnas Controls NEMA general purpose contactors and motor starters serve three-phase motor control applications in commercial HVAC, industrial, and process equipment. Furnas motor starters include both non-reversing and reversing configurations in NEMA sizes, covering single-phase and three-phase full voltage starting applications. Furnas non-reversing motor starters are available in 3-pole, 45-amp configurations rated for 50/60 Hz service at 110/120V and 220/240V to match standard commercial HVAC control voltage requirements. The Furnas Innova Plus contactor series and Innova 45 series are general purpose contactor lines with broad coil voltage availability. NEMA-rated Furnas starters provide overload protection through built-in thermal overload relays sized to the motor being controlled.

IEC Contactors

Furnas Controls IEC contactors, including the 3RT2 series (marketed under Siemens), provide compact motor control for three-phase applications where IEC-standard equipment is specified. IEC contactors from the Furnas/Siemens line are available in a range of current ratings including 25A and 32A at 24V coil voltage, covering commercial HVAC pump, fan, and compressor motor applications. The IEC contactor format is more compact than equivalent NEMA-rated contactors, which may be advantageous in panel builds with limited enclosure space. Where a NEMA Furnas contactor is the standard choice for replacement in existing North American equipment, the IEC contactor format is appropriate for new panel construction or equipment using IEC-standard motor control components.

Contact Kits, Coils, and Accessories

Furnas Controls contact kits, rebuild kits, auxiliary contacts, and coils are available for service and replacement of existing Furnas contactor and starter installations. Contact kits allow worn main contacts to be replaced without purchasing a complete new contactor, reducing replacement cost on high-cycle HVAC compressor and fan applications. Furnas auxiliary contact blocks add normally-open or normally-closed pilot contacts to an existing contactor for control circuit interlocking. Rebuild kits restore a Furnas contactor to serviceable condition by replacing main contacts, arc chutes, and springs in a single kit. The broad availability of Furnas replacement parts through SupplyHouse supports field service on existing installed Furnas motor control.

Why Contractors Specify Furnas Controls

HVAC contractors and electrical technicians specify Furnas Controls motor control products because the Furnas definite purpose contactor is among the most widely installed contactor types in North American HVAC equipment, providing extensive technician familiarity and broad replacement parts availability through electrical and HVAC supply channels. The Furnas Centurion 2000 definite purpose line covers 25 to 210 amps across a single product family, reducing the number of contactor families a contractor needs to stock for HVAC compressor and fan replacement work. Furnas contact kits and rebuild kits allow field repair of existing Furnas contactors without full unit replacement, which can reduce material cost on high-cycle compressor contactor replacements. Furnas motor starters include built-in thermal overload relay protection for the controlled motor. Furnas Controls products are available through SupplyHouse across contactors, starters, coils, and replacement parts.

How to Choose a Furnas Controls Product

The primary selection variable for a Furnas Controls contactor is application type: definite purpose or general purpose. Definite purpose Furnas contactors (Centurion 2000) are the standard choice for HVAC compressor and fan motor control in split-system and packaged equipment. General purpose NEMA-rated Furnas contactors and starters serve three-phase industrial and commercial HVAC applications where NEMA-rated motor control is specified.

The second variable is amperage rating. Match the Furnas contactor or starter amperage to the full-load amperage of the motor being controlled, plus a safety margin per the applicable electrical code. Furnas definite purpose contactors are available from 25A through 210A; NEMA general purpose contactors and starters cover a similar range in NEMA size designations. For replacement applications, match the existing contactor's pole count, amperage, and coil voltage.

The third variable is coil voltage. Furnas contactors are available with coil voltages of 24V, 110V, 120V, and 240V to match the control circuit voltage in the HVAC panel or motor control center. Confirm the coil voltage of the replacement Furnas contactor matches the existing control wiring before installation. For IEC contactor applications, confirm whether the IEC or NEMA format is appropriate for the specific panel or equipment design.

FAQs

Who manufactures Furnas Controls products today?

Furnas Controls products are now manufactured under the Siemens brand family. Furnas was acquired by Siemens, and Furnas-designated contactors, starters, and motor control components continue to be available through electrical and HVAC supply distributors including SupplyHouse for replacement and service applications.

What warranty does Furnas Controls offer on contactors and starters?

Furnas Controls warranty terms are available through Siemens product documentation. For specific warranty coverage on a Furnas definite purpose contactor or motor starter, consult the Siemens product data sheet or contact an authorized distributor.

What is the difference between Furnas definite purpose and general purpose contactors?

The difference between Furnas definite purpose and general purpose contactors is the application rating and physical format. Definite purpose Furnas contactors (Centurion 2000) are compact, application-specific units designed for HVAC, refrigeration, and related duty cycles. General purpose NEMA-rated Furnas contactors and motor starters are rated for broader industrial motor control applications and carry full NEMA motor control ratings. For HVAC compressor and fan replacement, the definite purpose Centurion 2000 is typically the appropriate choice.

How do I select the right amperage for a Furnas Controls replacement contactor?

Selecting the correct Furnas contactor amperage requires matching the contactor rating to the full-load amperage of the motor being controlled. For HVAC compressor contactors, the replacement contactor amperage must meet or exceed the rated-load amperage on the equipment nameplate. Furnas Centurion 2000 definite purpose contactors are available from 25A through 210A to cover residential and commercial HVAC compressor sizes.

Are Furnas contact kits compatible with older Furnas contactor bodies?

Furnas contact kits are designed for use in specific Furnas contactor model series. Match the contact kit model number to the contactor body being serviced. Furnas rebuild kits are also available and include main contacts, arc chutes, and springs for a more complete restoration of a worn Furnas contactor without full unit replacement.

What coil voltages are available for Furnas Controls contactors?

Furnas Controls contactors are available with coil voltages of 24V, 110V, 120V, and 240V to match standard HVAC and industrial control circuit voltages. Confirm the control circuit voltage at the installation point before ordering a replacement Furnas contactor. The coil voltage is marked on the existing contactor body and must match the replacement to prevent coil damage.