---
product_id: 51473857
title: "A421ABC-02C A421 Series Electronic Temperature Control, -40 to 212 Degree F Temperature Range, Single-Pole, Double-Throw"
brand: "johnson controls"
price: "฿12160"
currency: THB
in_stock: true
reviews_count: 13
category: "Johnson Controls"
url: https://www.desertcart.co.th/products/51473857-a421abc-02c-a421-series-electronic-temperature-control-40-to-212
store_origin: TH
region: Thailand
---

# Backlit LCD with adjustable brightness Single-pole, double-throw relay Wide -40 to 212°F range A421ABC-02C A421 Series Electronic Temperature Control, -40 to 212 Degree F Temperature Range, Single-Pole, Double-Throw

**Brand:** johnson controls
**Price:** ฿12160
**Availability:** ✅ In Stock

## Summary

> 🌟 Take control of your climate with precision and style!

## Quick Answers

- **What is this?** A421ABC-02C A421 Series Electronic Temperature Control, -40 to 212 Degree F Temperature Range, Single-Pole, Double-Throw by johnson controls
- **How much does it cost?** ฿12160 with free shipping
- **Is it available?** Yes, in stock and ready to ship
- **Where can I buy it?** [www.desertcart.co.th](https://www.desertcart.co.th/products/51473857-a421abc-02c-a421-series-electronic-temperature-control-40-to-212)

## Best For

- johnson controls enthusiasts

## Why This Product

- Trusted johnson controls brand quality
- Free international shipping included
- Worldwide delivery with tracking
- 15-day hassle-free returns

## Key Features

- • **User-Friendly Interface:** Bright backlit LCD and intuitive three-button touchpad make setup and monitoring effortless, even in low light.
- • **Seamless Relay Switching:** Single-pole, double-throw output ensures reliable, crisp on/off control for heating or cooling systems.
- • **Built to Last, Made in USA:** Durable Johnson Controls craftsmanship ensures long-term reliability and peace of mind for your critical systems.
- • **Customizable Control Security:** Lock user adjustments to prevent unauthorized changes—ideal for professional settings demanding consistency.
- • **Precision Temperature Mastery:** Control temps from freezing cold to boiling hot with a -40 to 212°F range—perfect for any environment.

## Overview

The Johnson Controls A421ABC-02C is a robust single-stage electronic temperature control featuring a wide -40 to 212°F range, a reliable single-pole, double-throw relay, and a bright backlit LCD with adjustable brightness. Designed for professional HVAC and industrial applications, it offers user adjustment locks, anti-short cycle delay, and sensor offset capabilities. Made in the USA, this control is a direct replacement for the A419ABC-1C, delivering dependable, precise temperature management for heating and cooling systems.

## Description

Direct Replacement To The A419Abc-1C The A421 Series Electronic Temperature Controls Are Single-Stage Controls With A Single-Pole, Double-Throw (Spdt) Output Relay. A421 Controls Feature A Bright Backlit Lcd With Adjustable Brightness And A Three-Button Touchpad Interface That Can Be Set Up To Restrict User Adjustments. An Led Indicates The Output Relay's On/Off Status. Standard A421 Series Control Modules Have Simple On And Off Temperature Settings For Heating Or Cooling, An Adjustable Anti-Short Cycle Delay, Temperature Setback, And Sensor Offset Capability. Made in United States. Manufactured by Johnson Controls.

Review: The A419 works best for some applications as it has a differential setting ... - I have 2 A419 and 1 A421. I have used them at times control a fish smoker a heating pad for seedling starting and to control the blower on a gas heater. The A419 works best for some applications as it has a differential setting that follows a set point that has to be changed often as in smoking fish and I only have to make 1 adjustment each time. The A 421 works good for a set point that remains fairly constant as in a blower control for a heater. In using both the A419 and A421 I have a contactor for the final switching heaters for smoking. It seems the sensors are interchangeable which is a nice feature as I has one fail "sF" while smoking fish so I had a spare from one of the other ones not in use.
Review: Keeps the lobster tank temp exactly as set - we were having trouble with the old analog controls they had a tendency to stick now the bate minnows are very happy with the temp not fluctuating

## Features

- Single-stage controls
- Single-pole
- Double-throw
- The temperature control range is -40 to 212°f or -40 to 100°c

## Technical Specifications

| Specification | Value |
|---------------|-------|
| ASIN | B01IWJO25E |
| Best Sellers Rank | #63,173 in Industrial & Scientific ( See Top 100 in Industrial & Scientific ) #95 in Temperature Controllers |
| Date First Available | October 27, 2016 |
| Global Trade Identification Number | 10662011536502 |
| Is Discontinued By Manufacturer | No |
| Item Weight | 1.15 pounds |
| Item model number | A421ABC-02C |
| Manufacturer | Johnson Controls |
| Product Dimensions | 11.1 x 4.1 x 4.3 inches |
| UPC | 645220630707 |

## Product Details

- **Brand:** Johnson Controls
- **Color:** black, gray
- **Display Type:** LED
- **Item Weight:** 1.15 Pounds
- **Operating Temperature:** 212 Degrees Fahrenheit

## Images

![A421ABC-02C A421 Series Electronic Temperature Control, -40 to 212 Degree F Temperature Range, Single-Pole, Double-Throw - Image 1](https://m.media-amazon.com/images/I/51MLSNZqh8L.jpg)

## Customer Reviews

### ⭐⭐⭐⭐⭐ The A419 works best for some applications as it has a differential setting ...
*by E***D on May 22, 2018*

I have 2 A419 and 1 A421. I have used them at times control a fish smoker a heating pad for seedling starting and to control the blower on a gas heater. The A419 works best for some applications as it has a differential setting that follows a set point that has to be changed often as in smoking fish and I only have to make 1 adjustment each time. The A 421 works good for a set point that remains fairly constant as in a blower control for a heater. In using both the A419 and A421 I have a contactor for the final switching heaters for smoking. It seems the sensors are interchangeable which is a nice feature as I has one fail "sF" while smoking fish so I had a spare from one of the other ones not in use.

### ⭐⭐⭐⭐⭐ Keeps the lobster tank temp exactly as set
*by E***S on July 17, 2024*

we were having trouble with the old analog controls they had a tendency to stick now the bate minnows are very happy with the temp not fluctuating

### ⭐⭐⭐⭐⭐ Boring...
*by T***D on December 12, 2020*

This is a boring product, as it should be. Once I deciphered the instructions and got it wired up and configured, it's worked without any fuss. The menu system isn't the most obvious, but once you figure it out, it's acceptable. Our fridge went out and I used this to convert a wine/beer fridge which only went down to 40F. I chose this over other cheaper ones because it has an anti-short cycle mode which is important for refrigeration to keep from damaging the compressor.

## Frequently Bought Together

- Johnson Controls A421ABC-02C A421 Series Electronic Temperature Control, -40 to 212 Degree F Temperature Range, Single-Pole, Double-Throw
- PITCO 60125501 Thermopile Millivolt

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*Product available on Desertcart Thailand*
*Store origin: TH*
*Last updated: 2026-02-20*