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JOHNSON CONTROLS Temperature Control: Single Stages, Heat and Cool, -40°F to 212°F, Digital - Single-Stage Electronic Temperature Controls
JOHNSON CONTROLSSingle-Stage Electronic Temperature Controls

JOHNSON CONTROLS Temperature Control: Single Stages, Heat and Cool, -40°F to 212°F, Digital

The JOHNSON CONTROLS A421GEF-01C is a single-stage electronic temperature control for heating applications. It operates with a 24V AC input voltage and is compatible with the A99 series. The control features a SPDT…

SKU 3G-OTH-68841

Also listed as: A421GEF01C · A421GEF 01C

Brand
JOHNSON CONTROLS
Item
Temperature Control: Single Stages, Heat and Cool, -40°F to 212°F, Digital
Category
Single-Stage Electronic Temperature Controls
Available to Order
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Local availability & support — Singapore

Local office
20 Woodlands Link #09-05, Singapore 738733
Phone
+65 8878 8355
Delivery
Same-day or next-business-day delivery within Singapore for in-stock items; 7–14 days for factory-order parts from Europe.
Payment
Invoicing in SGD. PayNow, bank transfer, and corporate PO accepted.
Ships to
Singapore

Technical Specifications

JOHNSON CONTROLS
Manufacturer Part Number
A421GEF-01C
Type
Heat and Cool, -40°F to 212°F, Digital, 4X, SPDT, A99
AC
24V
Application
Heating Control
Product Type
Temperature Control
Input Voltage
24V AC
Compatible with Series
A99
Variable Output Voltage
No

Technical Documents

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JOHNSON CONTROLS Products
3G Electric (S) Pte. Ltd. — Singapore

Product Description

The JOHNSON CONTROLS A421GEF-01C is a single-stage electronic temperature control for heating applications. It operates with a 24V AC input voltage and is compatible with the A99 series. The control features a SPDT output and a digital display, with a temperature range of -40°F to 212°F.

Frequently Asked Questions

What is the JOHNSON CONTROLS A421GEF-01C temperature control used for?

The JOHNSON CONTROLS A421GEF-01C is a single-stage electronic temperature control designed for heating applications. It is commonly used in HVAC systems to regulate temperature in commercial and industrial environments, providing reliable on/off control with a digital display and SPDT output.

What are the specifications of the JOHNSON CONTROLS A421GEF-01C?

The A421GEF-01C operates on 24V AC input voltage and has a temperature range of -40°F to 212°F. It features a SPDT output, digital display, and is compatible with the A99 series. The control is rated NEMA 4X and is designed for heating control applications.

Where to buy the JOHNSON CONTROLS A421GEF-01C worldwide?

3G Electric supplies the JOHNSON CONTROLS A421GEF-01C temperature control worldwide. As a global industrial equipment distributor, we handle full logistics, customs clearance, and delivery to your location. Contact us for availability and lead time.

How to install the JOHNSON CONTROLS A421GEF-01C temperature control?

Install the A421GEF-01C by mounting it in a dry location, connecting 24V AC power to the input terminals, and wiring the SPDT output to your heating load. Set the desired temperature using the digital interface. Always follow local electrical codes and consult the manufacturer's manual for detailed wiring diagrams.

Used in

Common applications for JOHNSON CONTROLS
Industrial refrigeration — Johnson Controls P170SA-1C dual pressure control for compressor protection in ammonia or halocarbon systems
Chiller plant automation — Johnson Controls VA7810-HGA-2 electric globe valve actuator for modulating chilled water flow in VG7000 series valves
Pneumatic HVAC retrofit — Johnson Controls T-4002-302 conversion kit for upgrading existing Robertshaw thermostats in commercial buildings
Cooling tower water management — Johnson Controls V-4332-1007 pneumatically actuated diaphragm valve for 3-way diverting of water flow
Boiler fuel oil pressure monitoring — Johnson Controls P545NCB-25C electronic lube oil pressure control with alarm for burner management systems
Process pressure sensing — Johnson Controls P599AAPS105C pressure transmitter with IP67 rating for washdown zones in food and beverage plants

JOHNSON CONTROLS Products

3G Electric supplies JOHNSON CONTROLS single-stage electronic temperature controls. We supply genuine products with in-stock availability on common SKUs, technical documentation, commissioning support, and warranty service — worldwide.

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Compatible alternatives & equivalents

Cross-referenced by specification & description
Temperature Control: Single Stages, Heat and Cool, -40°F to 212°F, Digital, 1, SPDT, 24V AC, A99 (MPN A421GBF-02C)
JOHNSON CONTROLS
Temperature Control: Single Stages, Heat and Cool, -40°F to 212°F, Digital, 1, SPDT, 24V AC, A99 (MPN A421GBF-02C)
Temperature Control: Single Stages, Heat and Cool, -40°F to 212°F, Digital, 4X, SPDT, 24V AC, A99 (MPN A421GEF-02C)
JOHNSON CONTROLS
Temperature Control: Single Stages, Heat and Cool, -40°F to 212°F, Digital, 4X, SPDT, 24V AC, A99 (MPN A421GEF-02C)
Temperature Control: Single Stages, Heat and Cool, -40°F to 212°F, Digital, 4X, SPDT, A99 (MPN A421AEC-01C)
JOHNSON CONTROLS
Temperature Control: Single Stages, Heat and Cool, -40°F to 212°F, Digital, 4X, SPDT, A99 (MPN A421AEC-01C)
Temperature Control: Single Stages, Heat and Cool, -40°F to 212°F, Digital, 4X, SPDT, A99 (MPN A421AED-01C)
JOHNSON CONTROLS
Temperature Control: Single Stages, Heat and Cool, -40°F to 212°F, Digital, 4X, SPDT, A99 (MPN A421AED-01C)
Temperature Control: Single Stages, Cool Only, -40°F to 212°F, Digital, 1, SPDT, 120V AC/240V AC (MPN A421ABT-02C)
JOHNSON CONTROLS
Temperature Control: Single Stages, Cool Only, -40°F to 212°F, Digital, 1, SPDT, 120V AC/240V AC (MPN A421ABT-02C)
Temperature Control: Single Stages, Heat and Cool, -40°F to 212°F, Digital, 1, SPDT, 120V AC/240V AC (MPN A421ABD-02C)
JOHNSON CONTROLS
Temperature Control: Single Stages, Heat and Cool, -40°F to 212°F, Digital, 1, SPDT, 120V AC/240V AC (MPN A421ABD-02C)

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Temperature Control: Single Stages, Heat and Cool, -40°F to 212°F, Digital, 1, SPDT, 120V AC/240V AC (MPN A421ABC-02C)
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Temperature Control: Single Stages, Heat or Cool, -40°F to 212°F, Digital, 1, SPDT, 120V AC/240V AC (MPN A421ABC-02)
Temperature Control: Single Stages, Heat and Cool, -40°F to 212°F, Digital, 1, SPDT, 120V AC/240V AC (MPN A421ABC-06C)
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Temperature Control: Single Stages, Heat and Cool, -40°F to 212°F, Digital, 1, SPDT, 120V AC/240V AC (MPN A421ABC-06C)
Temperature Control: Single Stages, Heat and Cool, -40°F to 212°F, Digital, 4X, SPDT, A99 (MPN A421AET-01C)
JOHNSON CONTROLS
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