How to Wire the nJoin Power Module to an OJ Control


In this video, we show you how to connect an OJ floor heating thermostat to our nJoin power module. The nJoin provides additional power to floor heating systems that exceed 15 amps, making it easier to heat large areas on a single control. The nJoin power module can be paired with any model in our nSpiration series of thermostats.

Video Transcript

Hello, and welcome to today's video. My name is Scott, I am from WarmlyYours and we today are going to be talking about how to hook up a system that requires more than 15 amps. So if you take a look at these two controls, you can see one is a thermostat and one is a power module. The thermostat can switch up to 15 amps and a thermostat will work for most spaces. When you're doing a master bathroom, you can usually do it on one control. However, if you're doing like a basement renovation and you are doing a bar and maybe a part of a living space, that job may go past 15 amps and go to 20 or 25 or 28 amps. If that's the case, this will switch the first 15 and this will switch the next 15. This will allow you to heat very large spaces in your home. So let's take a look at the back of the thermostat to see what kind of connections need to be done here. The back of the thermostat is where you're going to be doing your high voltage connections. This is either going to be 120 volts or two 40 volts. Let's talk about real quickly what the difference of coverage area is between one, 20 and to 40, with one 20 available power being sent to the thermostat. This thermostat could switch up to about 120 square feet if you're going to be heating more than 120 square feet. The first thing you'd want to do is try to go to 240 volts, because that will then let you control up to 240 square feet using one thermostat. So if you are going beyond the 240 square feet, if you need to heat 300 square feet, if you need to heat 400 square feet, that's where you're going to need a thermostat and a power module. So let's go ahead and take a look at this cover that's on the back. This cover is very important because it helps protect the connections from the ground, hitting it when you're stuffing a lot of stuff in a little box. So please save this. Do not throw it away. So let's take a look at the wires. First of all, in our mock-up. Normally you'd be doing this in a wall, in a box, inside of a wall. But to make things clear, to make it easier to see, we're doing it like this on a tabletop. So let's take a look at this wire here. The black wire is the wire that's coming up from the floor if you notice, you have a yellow and a black wire. And if this were one 20, you'd need to pay attention to not this wire, but the wire underneath. Let's go ahead and talk about this wire. This wire, as we can see, is some Roma wire, which represents the wire in your wall coming up from your circuit breaker. If we take a look at this, you can see there's a white and a black that normally indicates that it's a 120 volt system, so this would be the neutral. This would be the line with the wire from the floor. We don't need to worry about polarity. There is no polarity in the mat, in the floor. We get that question all the time. Do I need to make sure that this wire is any certain way on the thermostat? And the answer to that is no, there is no polarity on this wire. However, the wire coming from the circuit breaker does require you to respect the polarity. If this were to 40, this would be a hot and a hot if this is 120. This would be your line and a neutral. So those are your connections done at the back of the thermostat. So let's talk about color coordinating and the connections that aren't done on the screws. So let's take a look at this wire. This is the wire coming up from the floor. It's the black wire with the yellow and the black inside and a braided ground, which you can see here. If this were to 40, this would be red and black with the ground. A lot of people ask, where do I connect the ground to the thermostat? And the answer to that is you don't you hook the ground from the floor up through the ground come from the circuit breaker? It does not get attached to the thermostat. Your connection is free of the thermostat. Your ground gets attached to the house ground with a wire nut. So now we can see the connections at the back of the thermostat and the back of the power module. These two connect exactly the same. That's how you do your high voltage wiring. Now, if you're doing a large installation, this thermostat should be on its own dedicated line and this power module should be on its own dedicated line. They should not share the circuit breaker. The circuit breaker should also be a non PSI circuit breaker because the GFCI protection is included in the thermostat and the power module. And if you take a look real carefully, you'll notice that the base of each they're exactly the same. So that's why they wire exactly the same. Let's talk about the blue and white connection that has to be done. Well, we've talked about this needs to be on its own circuit breaker. This needs to be on its own circuit breaker. How does the power module know when to turn on? At the correct time, that is because it's told to turn on by the thermostat and it's told to be turned on using the blue and the White wires. Those are the low voltage communication wires between the two. So let's take a look at the front of the controls and see what we need to do with a low voltage connection. I've disconnected the high voltage connection from the back of this thermostat just to make it easier to see because what we're going to be talking about now is actually a couple of low voltage connections that have to be done on the thermostat and one low voltage connection that's done on the power module. Now our connections in the back are done with the normal Philips screwdriver. The connections that we're going to be doing on the front of the thermostat are going to require a much smaller thermostat screw. So let's go ahead and take a look at our connections here. We've taken the faceplates off and now, as I promised, you can see that these two bases are identical, so they are the same. So let's go ahead and take a look at our low voltage connections now. This is the power module. Notice how we have one connection. OK, what we're going to do now is we're going to talk about the thermostat. The thermostat has two low voltage connections, one of them for the thermostat wire. And you may be asking yourself, where is the thermostat wire? The thermostat wire is in the same box as the thermostat when you're doing your installation. Do not forget to take the thermostat sensor out of the box and give it to the TilePro when they're putting the tile in, because this needs to go in at the same time the tile does. It can then be hooked up later to the thermostat, so make sure you take this out of the box. Give it to the person doing your tile so it can get installed per the instruction manual. So now let's talk about our thermostat connection for our thermostat sensor. If we look on the wiring terminals here, we can see C and D on the terminals and it says in and sensor those are the two that we want to hook the sensor into. The sensor has two little wires and there is no polarity in that wire. It doesn't matter which one goes in c, and it doesn't matter which one goes in d, just as long as they're both in. So there is our thermostat connection for our thermostat sensor. Notice on this power module, the power module does not get a thermostat input. Now that we've talked about the sensor connection, let's talk about this connection here on and b, and B is the low voltage connection that runs to the power module, and that's how the thermostat turns the power module on and off. If you do not get this connection correct, when the unit is asking for heat or calling for heat, it'll actually turn the power module off. If the polarity is reversed, so you'll know right away if you've installed this wire incorrectly, because when the thermostat turns on, this will turn off. When the thermostat turns off, this one will turn on. This is the connection. You really have to worry about your polarity. So let's take a look at the wires that we've attached here, and it's very important that you get the polarity correct. So if we take a look here, we can see and B a needs to go to C on the power module. B needs to go to D on the power module. So it's very, very important that you get that polarity done correctly. So now we can see our low voltage connections on the thermostat, respecting the polarity of the blue and the White wires, and there is no polarity of the sensor wire. So it's very, very important when you do this installation that these low voltage wires do not get put in the same conduit as the high voltage wires coming from the circuit breaker or running down to the floor. It's very, very important that your thermostat sensor wire is not installed in the same conduit as the leads running from the floor up to the thermostat because it will obliterate the low voltage signal. And it may be against your local Electrical Code to put a low voltage wire in the same conduit as a high voltage wire. So that's how your low voltage connections are done on the front of the thermostat. If you respect the polarity of the blue and the White wires, you should have a problem-free installation. So Thanks for watching our video on how to install a power module and thermostat combination on jobs requiring more than 15 amps.

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