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RC840T-240 On/Off Switching Electric Heating Relay with Built-in 24 V Transformer, Black
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Shipping & Fee Details
| Price | $44.85 | |
| AmazonGlobal Shipping | $14.90 | |
| Estimated Import Fees Deposit | $0.00 | |
| | ||
| Total | $59.75 | |
Learn more
Return this item for free
Free returns are available for the shipping address you chose. You can return the item for any reason in new and unused condition: no return shipping charges.
Learn more about free returns.- Go to your orders and start the return
- Select your preferred free shipping option
- Drop off and leave!
Shipping & Fee Details
| Price | $44.85 | |
| AmazonGlobal Shipping | $14.90 | |
| Estimated Import Fees Deposit | $0.00 | |
| | ||
| Total | $59.75 | |
Purchase options and add-ons
- Direct replacement for any brand name relay
- Built-in 24 V transformer for easy installation.
- Compatible with 24V thermostats with 2-wire connections (R,W) or 3-wire connections (R,W,C)
- Immediate relay activation provides improved temperature control and comfort
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Customer reviews
Customer Reviews, including Product Star Ratings help customers to learn more about the product and decide whether it is the right product for them.
To calculate the overall star rating and percentage breakdown by star, we don’t use a simple average. Instead, our system considers things like how recent a review is and if the reviewer bought the item on Amazon. It also analyzed reviews to verify trustworthiness.
Learn more how customers reviews work on AmazonCustomers say
Customers like the functionality, ease of installation, and temperature control of the product. They mention it works great, is super easy to install, and perfect for regulating heat with multiple rooms from one low-voltage thermostat. Some appreciate the build quality and relay quality. However, some customers have different opinions on the value for money.
AI-generated from the text of customer reviews
Customers are satisfied with the functionality of the product. They mention it works perfectly for replacing the old control unit in the heater, and the baseboard heaters are back to working great. Some say it's easy to install and works great to convert a three-wire or more smart thermostat.
"...I installed on a 1500W baseboard heater. Works great. Don't go for the cheap fire hazard alternatives." Read more
"...I found this diagram for this specific model and it worked perfectly and was super easy to install...." Read more
"...It’s been 3 months since the installation, and it works flawlessly. I will be purchasing others to control baseboard heaters next." Read more
"...Wiring is easy, and works as it should. I tucked the unit behind the old gang box so it was out of the way. It'll save me money over time." Read more
Customers find the installation of the product easy. They mention it's simple and easy to use. Customers also say the directions and wiring diagrams are well-written and easy to follow.
"...for this specific model and it worked perfectly and was super easy to install...." Read more
"...Wiring is easy, and works as it should. I tucked the unit behind the old gang box so it was out of the way. It'll save me money over time." Read more
"...easy to install and use, relay and 24v for thermostat in one unit." Read more
"...install a 5000 watt Comfort Zone 240 volt garage heater and it installed pretty easily...." Read more
Customers like the temperature control of the product. They mention it's perfect for regulating heat with multiple rooms from one low-voltage thermostat, making electric heating simple, and that it can now be controlled from anywhere. Some say it's a very efficient heating system with zero maintenance.
"...the temp from the comfort of my home and when ready to work, it's nice and warm...." Read more
"...Enerjoy panels 25 years ago and they have proved to be a very efficient heating system with zero maintenance required in those 25 years, and I’m..." Read more
"...So i really like that this one is instant heat. Overall it works well for my needs" Read more
"...Better temperature control is greatvas well.Installed the relay with 2 sided tape probably took 30 minutes at most from start to finish." Read more
Customers are satisfied with the control capability of the product. They mention it's great to have the ability to control the heating panels while away from home. It allows them to add a programmable thermostat to turn the heater down during peak hours of use. Additionally, they say it allows many more options of thermostats and that it handles line voltage.
"...It allowed me to add a programmable thermostat to turn the heater down during peak demand electricity. Also my heater was out of reach...." Read more
"...works just as I had hoped and it is great to have the capability to control the heating panels while away from home as well as having all the..." Read more
"...Of course you need a thermostat as well, but now I can control my shop heater so easily. It has worked flawlessly. There is no maintenance." Read more
"...Worked great. Being able to adjust the temp based on known hours of use is already saving money...." Read more
Customers are satisfied with the build quality of the product. They mention it's well-made and solid.
"...This is UL listed. It's is a solid quality product. I installed on a 1500W baseboard heater. Works great...." Read more
"...Value wise, i marked 3 stars, it's solidly built, has good gauge cables but is just expensive for what it is, and also very shortly after purchasing..." Read more
"...Plastic case seems rugged enough,so I will trust the UL/CSA ratings for flame retardancy. I like the visible LED indicator...." Read more
"...Just like a breaker in your breaker panel . This thing is extremely well made and solid...." Read more
Customers are satisfied with the relay quality. They mention it's easy to install, provides 24 volts to the thermostat, and is an instant-on relay.
"Great simple relay that can provide 24 volts to the thermostat along with the necessary C wire for smart thermostats...." Read more
"...Wonderful relay, easy to install. If you have old wiring like I do (1960's) and nothing is marked, just swap the leads if it doesn't work correctly...." Read more
"...Also, no time delay heat up element. They are instant on relays." Read more
"Great relay and transformer for heater..." Read more
Customers like the design of the product. They say it's nice, quiet, and tidy.
"...Very tidy and I love the LED light for when the relay is closed." Read more
"Item looks good and was easy to install" Read more
"This is a great little unit. Great design!" Read more
"...Nice and quiet." Read more
Customers have mixed opinions about the value for money of the product. Some mention it's a great little unit and a good upgrade to their work shops, while others say it's expensive for what it is.
"...It'll save me money over time." Read more
"...A super great price too! So happy I found this here." Read more
"...stars, it's solidly built, has good gauge cables but is just expensive for what it is, and also very shortly after purchasing, it went down in price..." Read more
"...let me put my heater controls in a more accessible spot at a reasonable price...." Read more
Reviews with images
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Top reviews
Top reviews from the United States
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Reviewed in the United States on February 10, 2022
Reviewed in the United States on March 3, 2024
1. I'm based in the UK
2. As a result, mains voltage here is 230-240vac at 50hz
3. So it stands to reason that all items i will be controlling and the supply to this relay/transformer/switch will also be that configuration of 230-240vac and 50hz
Secondly, the relay/transformer/switch works flawlessly for my needs.
So, why the odd title you ask, well, purchasing such an item from the USA was obviously an odd choice, however a financially beneficial one for myself, put bluntly, it was cheaper, even taking into account shipping and additional tax applied to the price, it was just a better deal than buying through amazon.co.uk
Obviously there were warnings from Amazon.com (usa) because it's designed operating voltage does not match the mains voltage specifications there in the US
I have pictured the item i received, and as you can clearly see, it says "Load (Res) 208-240v /22A 60Hz"
yet the images used to sell the item clearly show "50 / 60Hz"
Now, remember that my supply and equipment is all 230-240vac 50Hz, and there was at least one warning regarding the voltage not matching US supply, the images are inaccurate in relation to the Hz rating, which is disappointing.
In reality, it appears the unit itself works quite happily at 230-240vac 50Hz outputting bang on 24vac, and the Resistive Load rating of 22A is somewhere in the region of 3 times more than I need is not of a concern to me that the 22A may not be accurate given i use 50Hz and that rating was specified at 60Hz, like i said, just a little disappointing.
Value wise, i marked 3 stars, it's solidly built, has good gauge cables but is just expensive for what it is, and also very shortly after purchasing, it went down in price (more than just exchange rate related.)
Reviewed in the United States on December 14, 2023
1. I'm based in the UK
2. As a result, mains voltage here is 230-240vac at 50hz
3. So it stands to reason that all items i will be controlling and the supply to this relay/transformer/switch will also be that configuration of 230-240vac and 50hz
Secondly, the relay/transformer/switch works flawlessly for my needs.
So, why the odd title you ask, well, purchasing such an item from the USA was obviously an odd choice, however a financially beneficial one for myself, put bluntly, it was cheaper, even taking into account shipping and additional tax applied to the price, it was just a better deal than buying through amazon.co.uk
Obviously there were warnings from Amazon.com (usa) because it's designed operating voltage does not match the mains voltage specifications there in the US
I have pictured the item i received, and as you can clearly see, it says "Load (Res) 208-240v /22A 60Hz"
yet the images used to sell the item clearly show "50 / 60Hz"
Now, remember that my supply and equipment is all 230-240vac 50Hz, and there was at least one warning regarding the voltage not matching US supply, the images are inaccurate in relation to the Hz rating, which is disappointing.
In reality, it appears the unit itself works quite happily at 230-240vac 50Hz outputting bang on 24vac, and the Resistive Load rating of 22A is somewhere in the region of 3 times more than I need is not of a concern to me that the 22A may not be accurate given i use 50Hz and that rating was specified at 60Hz, like i said, just a little disappointing.
Value wise, i marked 3 stars, it's solidly built, has good gauge cables but is just expensive for what it is, and also very shortly after purchasing, it went down in price (more than just exchange rate related.)
Update 5-12-2020= the heater fan got loud and it's super inefficient. The nest and this transformer worked great. I'm going to be insulating more. It cost half as much to keep my shop at 45deg f as it did to hear my entire 2500 sqft house.
