---
product_id: 5010882
title: "Aube Technologies 300612 RC840 On/Off Switching Electric Heating Relay"
brand: "honeywell"
price: "¥23173"
currency: JPY
in_stock: true
reviews_count: 12
url: https://www.desertcart.jp/products/5010882-aube-technologies-300612-rc840-on-off-switching-electric-heating-relay
store_origin: JP
region: Japan
---

# Direct replacement Soundproofed relay 24V compatibility Aube Technologies 300612 RC840 On/Off Switching Electric Heating Relay

**Brand:** honeywell
**Price:** ¥23173
**Availability:** ✅ In Stock

## Summary

> 🔥 Elevate Your Comfort Game!

## Quick Answers

- **What is this?** Aube Technologies 300612 RC840 On/Off Switching Electric Heating Relay by honeywell
- **How much does it cost?** ¥23173 with free shipping
- **Is it available?** Yes, in stock and ready to ship
- **Where can I buy it?** [www.desertcart.jp](https://www.desertcart.jp/products/5010882-aube-technologies-300612-rc840-on-off-switching-electric-heating-relay)

## Best For

- honeywell enthusiasts

## Why This Product

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

## Key Features

- • **Universal Fit:** Seamlessly replaces any brand name relay, ensuring hassle-free installation.
- • **Compact Design:** Lightweight and space-saving dimensions make it perfect for any setup.
- • **Energy Efficient:** Low current consumption allows multiple relays to be controlled by a single thermostat.
- • **Precision Control:** Experience immediate relay activation for optimal temperature management.
- • **Whisper-Quiet Operation:** Enjoy a peaceful environment with our epoxy-soundproofed relay design.

## Overview

The Aube Technologies 300612 RC840 On/Off Switching Electric Heating Relay is a versatile and efficient solution for temperature control, compatible with 24V thermostats and designed for quiet operation. Its compact size and low energy consumption make it an ideal choice for modern heating systems.

## Description

The RC840 Electric Heating Relay is designed to control a line voltage resistive load from a 24V control signal. It is compatible with 24V thermostats, and 24V thermostats with 2-wire connections (R, W) or 3-wire connections (R, W, C). The RC840 operates silently and can be installed in bedrooms, living rooms, or any other occupied area without disturbing occupants. The Electric Heating Relay can be installed on the side of an electrical box, a distribution panel, or inside the wiring compartment of an electric baseboard (see Owner's Manual for wiring diagrams). On a call for heat, the relay is immediately activated; there is no delay. This increases temperature control and comfort of the room.

## Features

- Compatible with 24V thermostats
- Direct replacement for any brand name relay
- Immediate relay activation provides improved temperature control and comfort
- Epoxy-soundproofed relay ensures quiet operation
- Low current consumption means multiple relays can be controlled by a single thermostat

## Technical Specifications

| Specification | Value |
|---------------|-------|
| Manufacturer | Aube |
| Part Number | 300612 |
| Item Weight | 4 ounces |
| Product Dimensions | 3 x 2 x 4 inches |
| Item model number | 300612 |
| Is Discontinued By Manufacturer | No |
| Item Package Quantity | 1 |
| Measurement System | Imperial |
| Batteries Included? | No |
| Batteries Required? | No |

## Images

![Aube Technologies 300612 RC840 On/Off Switching Electric Heating Relay - Image 1](https://m.media-amazon.com/images/I/81M3puELWvL.jpg)

## Customer Reviews

### ⭐⭐⭐⭐⭐ 5.0 out of 5 stars







  
  
    Works great, a little larger than expected
  

*by B***R on Reviewed in the United States on February 11, 2021*

This is a perfect match electrically, for things like the Radio Thermostat WiFi units that need to have 24 volts to run.  I was able to replace 3 old style full voltage thermostats with a combo of the modern thermostat and this relay with built-in 24 VAC transformer.  I just wish it was smaller.  I found it impossible to put in a single gang box with the other wiring needed.  It will just fit in a double gang box with wiring and wire nuts.

### ⭐⭐⭐⭐⭐ 5.0 out of 5 stars







  
  
    Great for connecting a 24v Thermostat to a 220v Electric Heating system.
  

*by J***  on Reviewed in the United States on January 8, 2021*

Used 2 of these to connect a Sensi Wifi Thermostat to my electric heat. I put one on each side of the 220v connection to turn off all electric connections at once. I then bought 1 more to also connect a second Sensi Thermostat to my Garage ceiling mount heater. These things work awesome.

### ⭐⭐⭐⭐⭐ 5.0 out of 5 stars







  
  
    Works great
  

*by Z***N on Reviewed in the United States on April 19, 2019*

Housing is plastic -- would prefer metal, but it's fine. Works as intended.

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**Shop now:** [https://www.desertcart.jp/products/5010882-aube-technologies-300612-rc840-on-off-switching-electric-heating-relay](https://www.desertcart.jp/products/5010882-aube-technologies-300612-rc840-on-off-switching-electric-heating-relay)

---

*Product available on Desertcart Japan*
*Store origin: JP*
*Last updated: 2026-02-24*