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JOHNSON CONTROLSSingle-Stage Electronic Temperature Controls

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

The JOHNSON CONTROLS A421GBF-02 is a single-stage electronic temperature control designed for boiler control applications. It operates on 24V AC input voltage and features a digital display with a temperature range…

SKU 3G-OTH-68708

Brand
JOHNSON CONTROLS
Item
Temperature Control: Single Stages, Heat or Cool, -40°F to 212°F, Digital
Category
Single-Stage Electronic Temperature Controls
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Technical Specifications

JOHNSON CONTROLS
Manufacturer Part Number
A421GBF-02
Type
Heat or Cool, -40°F to 212°F, Digital, 1, SPDT
AC
24V
Application
Boiler Control
Product Type
Temperature Control
Input Voltage
24V AC
Variable Output Voltage
No
View Full Spec Sheet

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

Product Description

The JOHNSON CONTROLS A421GBF-02 is a single-stage electronic temperature control designed for boiler control applications. It operates on 24V AC input voltage and features a digital display with a temperature range of -40°F to 212°F, utilizing a single-pole, double-throw (SPDT) switching action. This model does not provide variable output voltage.

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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Temperature Control: Single Stages, Heat or Cool, -40°F to 212°F, Digital, 1, SPDT, 120V AC/240V AC (MPN A421ABC-06). Key specifications — Variable Output Voltage: No; Manufacturer Part Number: A421ABC-06; Product Type: Temperature Control; Application: Cooling Control; Brand: JOHNSON CONTROLS; Input Voltage: 240V AC.
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Temperature Control: Single Stages, Heat or Cool, -40°F to 212°F, Digital, 1, SPDT, 120V AC/240V AC (MPN A421ABG-02). Key specifications — Variable Output Voltage: No; Manufacturer Part Number: A421ABG-02; Product Type: Temperature Control; Application: Chiller Control; Brand: JOHNSON CONTROLS; Input Voltage: 240V AC.
Temperature Control: Single Stages, Heat and Cool, -40°F to 212°F, Digital, 1, SPDT, 120V AC/240V AC (MPN A421ABG-02C). Key specifications — Variable Output Voltage: No; Manufacturer Part Number: A421ABG-02C; Product Type: Temperature Control; Application: Heating Control; Brand: JOHNSON CONTROLS; Input Voltage: 240V AC; Compatible with Series: A99.
JOHNSON CONTROLS
Temperature Control: Single Stages, Heat and Cool, -40°F to 212°F, Digital, 1, SPDT, 120V AC/240V AC (MPN A421ABG-02C). Key specifications — Variable Output Voltage: No; Manufacturer Part Number: A421ABG-02C; Product Type: Temperature Control; Application: Heating Control; Brand: JOHNSON CONTROLS; Input Voltage: 240V AC; Compatible with Series: A99.
Temperature Control: Single Stages, Heat and Cool, -40°F to 212°F, Digital, 1, SPDT, 120V AC/240V AC (MPN A421ABC-04C). Key specifications — Variable Output Voltage: No; Manufacturer Part Number: A421ABC-04C; Product Type: Temperature Control; Application: Damper Control; Brand: JOHNSON CONTROLS; Input Voltage: 120V AC; Compatible with Series: A99.
JOHNSON CONTROLS
Temperature Control: Single Stages, Heat and Cool, -40°F to 212°F, Digital, 1, SPDT, 120V AC/240V AC (MPN A421ABC-04C). Key specifications — Variable Output Voltage: No; Manufacturer Part Number: A421ABC-04C; Product Type: Temperature Control; Application: Damper Control; Brand: JOHNSON CONTROLS; Input Voltage: 120V AC; Compatible with Series: A99.
Temperature Control: Single Stages, Cool Only, -40°F to 212°F, Digital, 1, SPDT, 120V AC/240V AC (MPN A421ABT-02C). Key specifications — Variable Output Voltage: No; Manufacturer Part Number: A421ABT-02C; Product Type: Temperature Control; Application: Heating Control; Brand: JOHNSON CONTROLS; Input Voltage: 120V AC; Compatible with Series: A99.
JOHNSON CONTROLS
Temperature Control: Single Stages, Cool Only, -40°F to 212°F, Digital, 1, SPDT, 120V AC/240V AC (MPN A421ABT-02C). Key specifications — Variable Output Voltage: No; Manufacturer Part Number: A421ABT-02C; Product Type: Temperature Control; Application: Heating Control; Brand: JOHNSON CONTROLS; Input Voltage: 120V AC; Compatible with Series: A99.
Temperature Control: Single Stages, Heat and Cool, -40°F to 212°F, Digital, 1, SPDT, 120V AC/240V AC (MPN A421ABD-02C). Key specifications — Variable Output Voltage: No; Manufacturer Part Number: A421ABD-02C; Product Type: Temperature Control; Application: Fan Control; Brand: JOHNSON CONTROLS; Input Voltage: 240V AC; Compatible with Series: A99.
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Temperature Control: Single Stages, Heat and Cool, -40°F to 212°F, Digital, 1, SPDT, 120V AC/240V AC (MPN A421ABD-02C). Key specifications — Variable Output Voltage: No; Manufacturer Part Number: A421ABD-02C; Product Type: Temperature Control; Application: Fan Control; Brand: JOHNSON CONTROLS; Input Voltage: 240V AC; Compatible with Series: A99.

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Temperature Control: Single Stages, Heat and Cool, -40°F to 212°F, Digital, 4X, SPDT, 24V AC, A99 (MPN A421GEF-01C). Key specifications — Variable Output Voltage: No; Manufacturer Part Number: A421GEF-01C; Product Type: Temperature Control; Application: Heating Control; Brand: JOHNSON CONTROLS; Input Voltage: 24V AC; Compatible with Series: A99.
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Temperature Control: Single Stages, Heat and Cool, -40°F to 212°F, Digital, 4X, SPDT, 24V AC, A99 (MPN A421GEF-01C). Key specifications — Variable Output Voltage: No; Manufacturer Part Number: A421GEF-01C; Product Type: Temperature Control; Application: Heating Control; Brand: JOHNSON CONTROLS; Input Voltage: 24V AC; Compatible with Series: A99.
JOHNSON CONTROLS
JOHNSON CONTROLS
Temperature Control: Single Stages, Heat or Cool, -40°F to 212°F, Digital, 1, SPDT, 120V AC/240V AC (MPN A421ABC-02). Key specifications — Variable Output Voltage: No; Manufacturer Part Number: A421ABC-02; Product Type: Temperature Control; Application: Temperature Sensing and Control; Brand: JOHNSON CONTROLS; Input Voltage: 240V AC.
Temperature Control: Single Stages, Heat and Cool, -40°F to 212°F, Digital, 4X, SPDT, A99 (MPN A421AET-01C). Key specifications — Variable Output Voltage: No; Manufacturer Part Number: A421AET-01C; Product Type: Temperature Control; Application: Cooling Control; Brand: JOHNSON CONTROLS; Input Voltage: 120V AC; Compatible with Series: A99.
JOHNSON CONTROLS
Temperature Control: Single Stages, Heat and Cool, -40°F to 212°F, Digital, 4X, SPDT, A99 (MPN A421AET-01C). Key specifications — Variable Output Voltage: No; Manufacturer Part Number: A421AET-01C; Product Type: Temperature Control; Application: Cooling Control; Brand: JOHNSON CONTROLS; Input Voltage: 120V AC; Compatible with Series: A99.
Temperature Control: Single Stages, Heat and Cool, -40°F to 212°F, Digital, 1, SPDT, 120V AC/240V AC (MPN A421ABC-06C). Key specifications — Variable Output Voltage: No; Manufacturer Part Number: A421ABC-06C; Product Type: Temperature Control; Application: Fan Control; Brand: JOHNSON CONTROLS; Input Voltage: 120V AC; Compatible with Series: A99.
JOHNSON CONTROLS
Temperature Control: Single Stages, Heat and Cool, -40°F to 212°F, Digital, 1, SPDT, 120V AC/240V AC (MPN A421ABC-06C). Key specifications — Variable Output Voltage: No; Manufacturer Part Number: A421ABC-06C; Product Type: Temperature Control; Application: Fan Control; Brand: JOHNSON CONTROLS; Input Voltage: 120V AC; Compatible with Series: A99.
Temperature Control: Single Stages, Heat and Cool, -40°F to 212°F, Digital, 1, SPDT, 120V AC/240V AC (MPN A421ABC-03C). Key specifications — Variable Output Voltage: No; Manufacturer Part Number: A421ABC-03C; Product Type: Temperature Control; Application: Boiler Control; Brand: JOHNSON CONTROLS; Input Voltage: 120V AC; Compatible with Series: A99.
JOHNSON CONTROLS
Temperature Control: Single Stages, Heat and Cool, -40°F to 212°F, Digital, 1, SPDT, 120V AC/240V AC (MPN A421ABC-03C). Key specifications — Variable Output Voltage: No; Manufacturer Part Number: A421ABC-03C; Product Type: Temperature Control; Application: Boiler Control; Brand: JOHNSON CONTROLS; Input Voltage: 120V AC; Compatible with Series: A99.
Temperature Control: Single Stages, Heat and Cool, -40°F to 212°F, Digital, 4X, SPDT, A99 (MPN A421AED-01C). Key specifications — Variable Output Voltage: No; Manufacturer Part Number: A421AED-01C; Product Type: Temperature Control; Application: Chiller Control; Brand: JOHNSON CONTROLS; Input Voltage: 240V AC; Compatible with Series: A99.
JOHNSON CONTROLS
Temperature Control: Single Stages, Heat and Cool, -40°F to 212°F, Digital, 4X, SPDT, A99 (MPN A421AED-01C). Key specifications — Variable Output Voltage: No; Manufacturer Part Number: A421AED-01C; Product Type: Temperature Control; Application: Chiller Control; Brand: JOHNSON CONTROLS; Input Voltage: 240V AC; Compatible with Series: A99.
Temperature Control: Single Stages, Heat and Cool, -40°F to 212°F, Digital, 1, SPDT, 24V AC, A99 (MPN A421GBF-02C). Key specifications — Variable Output Voltage: No; Manufacturer Part Number: A421GBF-02C; Product Type: Temperature Control; Application: Cooling Control; Brand: JOHNSON CONTROLS; Input Voltage: 24V AC; Compatible with Series: A99.
JOHNSON CONTROLS
Temperature Control: Single Stages, Heat and Cool, -40°F to 212°F, Digital, 1, SPDT, 24V AC, A99 (MPN A421GBF-02C). Key specifications — Variable Output Voltage: No; Manufacturer Part Number: A421GBF-02C; Product Type: Temperature Control; Application: Cooling Control; Brand: JOHNSON CONTROLS; Input Voltage: 24V AC; Compatible with Series: A99.
Temperature Control: Single Stages, Heat and Cool, -40°F to 212°F, Digital, 1, SPDT, 120V AC/240V AC (MPN A421ABC-02C). Key specifications — Variable Output Voltage: No; Manufacturer Part Number: A421ABC-02C; Product Type: Temperature Control; Application: Boiler Control; Brand: JOHNSON CONTROLS; Input Voltage: 120V AC; Compatible with Series: A99.
JOHNSON CONTROLS
Temperature Control: Single Stages, Heat and Cool, -40°F to 212°F, Digital, 1, SPDT, 120V AC/240V AC (MPN A421ABC-02C). Key specifications — Variable Output Voltage: No; Manufacturer Part Number: A421ABC-02C; Product Type: Temperature Control; Application: Boiler Control; Brand: JOHNSON CONTROLS; Input Voltage: 120V AC; Compatible with Series: A99.