220V 240V On/Off Switch Electric Heating Relay with Built-in 24V Transformer, Replacement for Any Relay, Compatible with 24V Thermostat

This works great. Even better than the one I had to replace Has much better controls and more options

Very easy and simple to install. Very quiet and precise. I'll recommend it for a hydronic electric baseboard heater or regular electric baseboard heater.

Works perfectly and exactly as advertised. Key will be longevity. One design feature to be careful of with this is the instant on. If you end up cycling on and off and then back on there is potential to cause damage to your heating circuits. That is NOT a design flaw in this relay, but, a key feature consideration for your usage. That is how it is designed and it is perfect for my application. Most relays have a delay, some as long as 5 minutes.

After a long search for a relay to operate a 110V space heater with a typical thermostat, I found this. There wasn’t much information on 120V operation. Hooked it up…it works. Update: One of these two units is failing almost immediately after putting it to use.

After using another brand of this device, I was thrilled with the lower price for the same specs, but was a bit disappointed discovering the length of the control wires, which is way too short to reach any thermostat. It was easy to extend them, but why create an additional point of failure when the wires could have been about 6" longer. Also disappointing was the lack of a way to mount it to the j-box using a standard 1/2" collar nut. Installed and working great, but it could have been easier...

I purchased 2 of these units. The contactor box is compact and easily fit inside my garage heater housing. I mounted the contactor to the outside of my baseboard heater on one end. I hooked up WiFi thermostats to the 24-volt side. The built in 24volt supply worked great. Now i can control my garage heat remotely at my mountain home to accommodate overflow skiers. My makeshift garage office with the baseboard heat is also controlled with a thermostat that is on a schedule for my work day. This was the only compact relay i could find with the built in 24v transformer at a reasonable price.

I was able to use this to control a 240V load of 3 baseboard heaters (wired in parallel) from an Ecobee3 smart thermostat. I simply wired it up according to the provided diagram and everything worked perfectly. There's even a green LED light on the unit that indicates when it's activated. Note that if you plan to use your thermostat to control both baseboard heating (via this device) *and* an AC unit for cooling, this is considered a "dual transformer" configuration. In that case, the C wire must come from the cooling unit, not the heating unit, so you should use the 2-wire configuration (R and W only) for this device and leave the C (brown) wire disconnected.

I had installed another known brand similar device which failed after 4 years. With most active devices, it failed to full heat position, not ideal for energy consumption. This device has a convenient indication light, nice for troubleshooting. I used a separate 24vac source to power the Tstat, more than the internal power available from this device, since I needed a constant source to allow Redlink communications for this Tstat and have remote connectivity. Overall, quiet, works well. Installed in wall enclosure behind a hinged door.

I was on a brink of returning it, as it turned out a bit larger than I anticipated and couldn't fit in the wire box. Then I cut the drywall and the joist was ~1mm too close to fit it either. So I started my return and started exploring other options. But it turned out that pretty much any other option would be even thicker than this item. So I ended up shaving off 1mm of the joist and fitting it quite securely. It was some mental adjustment (and a triggered breaker) for the red wire not going to the red wire =) There's no audible hum or anything, although there's an audible click when relay switches (which is reasonable). Like others said, adding an extra inch or two to the wires wouldn't hurt at all, but most importantly it sits quite well (where others would not fit), Google Nest learning thermostat works flawlessly, and its cover panel fully covers the cutout. This is a great option for retrofitting an existing baseboard thermostat with a smart one. If you are adding a new wiring box though, I'd consider going with another product that has a proper locking nut.

This is great ! I easily converted the built-in, imprecise, non-gratuated thermostat in my garage 5000W heater with blower to an Ecobee smart and connected thermostat. From Stone age to AI age in 15 minutes. I just ran a 3-conductor thermostat wire to the Ecobee. Wire the 3 wires to corresponding colors. Find a place for this box inside the control compartment of the heater. The res Wire is the switched one. So One phase on the black, one on the blue, red to the thermostat signal. Et voila. Worked like a charm. For really cheap. Identical relays are over 100$ in Canada. This price is great !!!

Fonctionne très bien, les fils du thermostat pourraient être un peu plus long ça serait mieux

This is a great product to add a regular thermostat to any 5000W or lower electric heater. I used it for a garage heater and it has been working flawlessly for months now. I used a smart thermostat, so now I have the ability to see the temperature in the garage and adjust it remotely. I was just going to buy and add a separate transformer to step down the 240v to 24v and a relay with a 24v coil, but I stumbled across this and I’m very happy I did.

The HTACC-02 description is not accurate, it is not an exact replacement for most heating relays as its case doesn't have a threaded conduit hub mount like most heating relays, so it can't be mounted to a 1/2" knockout hole on the side of an electrical box like most heating relays. Also, this relay has no approval marks like UL, CSA, ETL, etc. so it is not Electrical Code compliant and shouldn't be used as an electrical heating relay. Aside from these issues, if you have some other use for it where code compliance isn't an issue, it appears to be decent quality and well-built for the most part. The transformer is just friction fit in a hole in the circuit board so could move if the relay took much of a jolt, a bit of hot glue on the backside of the board easily fixes this potential issue. I have attached some photos, including a photo of its installation guide, which is also not accurate as it also says the HTACC-02 can be attached on the side of an electrical box and shows a picture of a different relay (looks like a RC840T).