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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 A421ABC-03C is a single-stage electronic temperature control for boiler applications. It operates with a 120V AC input voltage and is compatible with the A99 series. The digital control features…

SKU 3G-OTH-68561

Also listed as: A421ABC03C · A421ABC 03C

Brand
JOHNSON CONTROLS
Item
Temperature Control: Single Stages, Heat and Cool, -40°F to 212°F, Digital
Category
Single-Stage Electronic Temperature Controls
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Delivery
Worldwide DHL shipping from Singapore; 7–14 business days door-to-door for most destinations.
Payment
Invoicing in USD. Bank transfer (SWIFT) and corporate PO accepted.

Technical Specifications

JOHNSON CONTROLS
Manufacturer Part Number
A421ABC-03C
Type
Heat and Cool, -40°F to 212°F, Digital, 1, SPDT
AC/240V AC
120V
Application
Boiler Control
Product Type
Temperature Control
Input Voltage
120V AC
Compatible with Series
A99
Variable Output Voltage
No

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

Product Description

The JOHNSON CONTROLS A421ABC-03C is a single-stage electronic temperature control for boiler applications. It operates with a 120V AC input voltage and is compatible with the A99 series. The digital control features a single SPDT output and a temperature range of -40°F to 212°F.

Frequently Asked Questions

What is the JOHNSON CONTROLS A421ABC-03C temperature control used for?

The JOHNSON CONTROLS A421ABC-03C is a single-stage electronic temperature control designed for boiler applications. It maintains temperature within a range of -40°F to 212°F, making it suitable for heating and cooling systems in commercial and industrial facilities.

What are the specifications of the JOHNSON CONTROLS A421ABC-03C?

The A421ABC-03C is a digital, single-stage temperature control with a single SPDT output. It operates on 120V AC input voltage, covers a temperature range of -40°F to 212°F, and is compatible with the A99 series. It does not have variable output voltage.

Where to buy the JOHNSON CONTROLS A421ABC-03C worldwide?

3G Electric supplies the JOHNSON CONTROLS A421ABC-03C 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 A421ABC-03C temperature control?

Install the A421ABC-03C by mounting it securely and wiring the 120V AC input and SPDT output per the wiring diagram. Ensure the sensor is properly placed for accurate temperature sensing. Follow standard electrical safety practices and consult the manufacturer's manual for detailed instructions.

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

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Temperature Control: Single Stages, Heat and Cool, -40°F to 212°F, Digital, 4X, SPDT, A99 (MPN A421AEC-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-04C)
Temperature Control: Single Stages, Heat and Cool, -40°F to 212°F, Digital, 1, SPDT, 120V AC/240V AC (MPN A421ABG-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 A421ABG-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
Temperature Control: Single Stages, Heat and Cool, -40°F to 212°F, Digital, 4X, SPDT, A99 (MPN A421AET-01C)
Temperature Control: Single Stages, Heat and Cool, -40°F to 212°F, Digital, 4X, SPDT, A99 (MPN A421AED-01C)
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Temperature Control: Single Stages, Heat and Cool, -40°F to 212°F, Digital, 4X, SPDT, A99 (MPN A421AED-01C)