In this instructional video, HVAC technicians discuss the Dragonfly leak‑detection module used for retrofitting mobile‑home and older gas‑furnace installations that lack built‑in refrigerant‑leak shutdowns. They explain the purpose of the black Dragonfly box and its blue sensor plug, describe the Molex black (thermostat) and green (equipment) connectors, and walk through the wiring process for both mobile‑home and legacy gas‑furnace setups. The speakers demonstrate the leak‑simulation test by pulling the blue pin, confirming that the unit shuts down and runs a continuous fan. They also cover integration with zone‑control boards—how a separate board can open all dampers and run the fan when a leak is detected. The conversation touches on the regulatory environment surrounding R‑32 and R‑454 refrigerants, noting that the perceived explosion risk is overstated. Finally, they stress best‑practice wiring safety: protecting wires that pass through metal holes, avoiding bare wire exposure to vibration, and using protective sleeves like Carflex to prevent shorts. The overall tone is hands‑on, cautionary, and focused on ensuring correct installation and reliable leak‑detection operation.
Chapters
Alright, R32454. If you've had any experience with any of these installing them, now you know that they've had some adds on to these things. Some of them, you know, your air handlers and all of that, they have your sensor inside that you got to pull through and plug in to make sure it's on. They are for in case you have a leak. That's a leak detection. That's just a— if it senses a leak, it— when you plug it into that board, what it does, as soon as it senses a leak, it turns on the indoor fan, lets the indoor fan so it can blow stuff out of the system or circulate it through to dilute what's there from being there. Now I can say they are going way overboard with what they're doing. For what they are, what this Freon is actually— the explosion point on this Freon. I think I told y'all before that you can take that Freon and put it in front of a torch and it just makes the torch brighter. That's all it does. It doesn't explode. It's not like taking a can of aerosol and sticking a lighter in front of it. It doesn't do that. But there is, you know how the government is, If there is any chance of anything, they go 10 steps out more than what they need to do to raise the cost on something. That's really what they're doing. And for mandates on these, you've got those sensors that plug in. Make sure we're plugging those in. If you don't, they won't come on anyway, uh, most of the time. But on your— let's talk about, um, mobile homes. And gas furnaces. Alright, they're not going to— well, the new gas furnaces will. If we do an install on a gas furnace and we're changing the coil and leaving the existing gas furnace, there's a chance we do that. We've done that before. The old one does not have sensors built into it for R-32 and the 454. The mobile home furnaces don't have that built into them, so they send us They send us a box called a Dragonfly. That's soldered into the line set? No, this actually plugs in. There's a sensor you mount, you plug it in, and then you take your wires from your unit and stuff and tie them. There's some Molex plugs in there, and then there's a plug down here for the sensor to plug into. It's called a Dragonfly. It's a little black box. Matter of fact, I might have a picture. Is that what you had me— Yeah, that's correct. All right, let me quit, man. Damn. All right, if you open that black box, it looks like this. All right, the little blue plug at the bottom is where your sensor and stuff plugs into. And what this does, it does the same thing as the board does. Once it senses a leak, refrigerant leak, it automatically shuts the unit down and turns the fan on. Continuous fan and lets it blow. That's what it does. On the old furnaces, these, you're going to have a green plug and you're going to have a black plug. Molex plug. If you look at the plug itself, right beside the black one, on top of it, it says thermostat. The other one is your equipment. Alright? So when you wire these into a mobile home, you— this is the black one. Your wires coming from the thermostat are going to wire to this plug. And if you zoom in on it, on the other side it will have your terminals marked just like they are on the thermostat. But you'll wire your thermostat to the black plug. The green one is for your equipment. You're going to bring your air handler and your condenser unit into this green plug and wire it to the green plug. There's going to be a couple of screws that you might have 2 wires under the same screw, but that's the way they've designed these so far. Okay, uh, when you get these wired and turn them on, what you need to do is let it run and then go over here and pull this this is the sensor that you're going to mount that comes in there. Go in there and pull this blue pin off the board. When you do, that simulates a leak. When you pull that pin, it should shut the air conditioning and all that down and let the continuous fan run. If it does not shut that system down, then something's not wired right. Now, there are— it's going to come with an install manual, and in that install manual it gives you about 6 different installation instructions. Those are for your newer systems, and it's going to say gas furnace, this and that. Those are for your newer systems. It does not have a wiring schematic for mobile homes, and it does not have your wiring schematic for your gas furnaces that you need on your existing ones.. But it does for your newer ones if you had one like that. I went through it. I met with the guy, the manufacturer. Me and him talked about it twice. You're going to need to make sure that you can remember how this is. The one that's for thermostat is thermostat only. The other with the green wire, the green plug is for your equipment. Wire your equipment to it. Start your system up. Make sure, make sure that before you leave, you pull that plug and test the system to make sure it's going to do what it needs to do. If not, you're going to have a problem. You're either going to have continuous fan running and it never shut off and it won't start the system up, or it starts the system up and then when it cycles off, the fan just won't cut off. Just make sure that it is, when you plug it back in, everything shuts down and the fan shuts off. Essentially just mounts anywhere around the evaporator core, right? That's right. That's right. Now, there is another one. We hadn't done one yet. If we add an R-32 system to an existing zone system, there is another board that they're going to send that's got to be tied to the zone system. What it does is if it senses a leak, it opens all dampers. And turns the fan on so it can circulate that stuff out of that system and just dilute it into the air. Do we have to change the zone board too, or no? No, it wires to the zone board. They're made to wire to the existing zone boards, and they send a command to open all dampers and turn on. Not as of yet that we have— that they have seen. They say, they say, but you know how that goes. That it will wire to any brands on board that there is and they will operate. Oh, but not that one. Yeah, he's got to be between his own board and— it's got— you're going to mount it in there, mount the sensor in the air handler or the evaporator. You got to get a wire from there back to that board that you're going to install, and then from that board to the zone board. But what terminal are we attaching it in the zone board to? That way I don't know that until we get the thing in. We ain't done one yet. But that board there, I won't know that until you look at the install manual. I don't have that answer yet. Like in a mobile home, where are you— where are we mounting this, uh, Dragonfly? Uh, anywhere down there in the compartment, down there around anywhere down there. You know how your thing slides off, you got that flat section, I'd wire it right there.
The wire comes right up from out of the unit, so it has to be right next to the wire.
So right there, you know, right on top of that little electrical about drains on mobile homes. You don't want that water falling. That's what I'm worried about. Just to add to the sensor, it's got a cover that goes on, guys.
I was reading through that manual, um, with that unit. There's a couple— so they know, for one, when the system is installed, all the wires connected, you got to connect the sensor before you turn the power on. Because it's specified that do not connect it with the power on. Is that— under no circumstances. After you put the sensor on it, then you start it, then you pull it through and activate the test. And then after you see it shut off, the outdoor unit fan going, he said kill the power again, put it back.
But there's no— there's no way— there's no reason for us to have activated the power on the system until we get it all wired in anyway. There's— we should never activate it till we know we're ready to start everything up. Everything, we shouldn't turn that on. I understand what Brian's saying.
I did see myself doing that. No, because I'm telling you, because there was one install that did happen and you just— everything was working except for the fan wouldn't shut off. Then what the manual said, which I don't know, you tell me, they talk to the guy. I was reading it, he's saying if the system have, um, cooling, heating, emergency heat, It says you need to go through each setting. To go to the thermostat, put in heat mode. Then once you activate the heat, the condenser kicks on, the fan kicks on, you pull it.
Well, you're supposed to test it in all function, all function, but we need, we need to get to the first point is test it period, getting into what's going on for it to happen. Um, all right, gas furnaces. Same as mobile homes, they're going to wire like this your existing gas furnaces. Now the new gas furnaces got shutdowns in them. You got your sensor that comes off your coil that you're going to mount in your coil, and it's going to come out and plug in just like it does on an air handler. Okay, Dragonfly is just pretty much for the older style units. Dragonfly is for anything that is going in existing in a mobile home right now because mobile homes don't have shutdowns in them. We leave an existing air handler If we leave an existing gas furnace, if we leave an existing— or we have a mobile home furnace, they're going to wire with the Dragonfly. You are in a mobile home or any unit and we were running a wire through a metal hole, there should not be bare wire laying on a metal, up against metal anywhere, because that unit is running and it's vibrating and that metal is going to cut through that wire and you're going to short it out. Whether it's the sensor or power wire or anything, if you've got to go through a hole that is not made for a Romex connector or something to go through, you need to protect your wire. Even if it's cut you a piece of Carflex to go over your wire to go through there to where it's laying on Carflex to go in there. Alright? Don't ever run a wire through a metal hole whether it's round, square, triangle, octagon, anything. If it's going through a hole without a connector, it's got to have protection on it. 'Cause that fan is running and it's vibrating. And it will— who was just at a— that was you. He was just at a unit Friday, Thursday or Friday. Wires coming off the compressor laying across the copper line. It shorted out. That line was laying there and that little vibration in that unit over a period of time ate the jacket off that wire, and finally the wire got copper. And guess what happened? It didn't— luckily it didn't blow a hole in the copper. That's what I told him, I said, luckily it didn't blow a hole in that copper. But you can see where it made connection with that copper and it shorted out and then all that. So just be careful.
