Inside an HVAC Unit: Safety & Components

 So we're gonna take a look at an HVAC system. I just took the panel off with my drill, took all the screws out, and you can see that it bowed out a little bit. Now this is a disconnect. So two things. Number one, always pull a disconnect and then two, check it still with your multimeter before you work on it.

Do whenever trusts that the disconnect actually disconnected the power. So hold the panel, pull, take this off, put it down. Now, I have already checked this with a multimeter, so I just want you to know that it's already been checked. You can notice. Let's look at a few things. Here's the fan. Here are the controls, a fuse link, a connector.

This is the transformer. This is a contactor. I. This is a block that brings the main wires, L one and L two, line one and line two. They each have 120 volts, sends 240 volts. And so this is the heating system. This is where the controls are, and this is the fan motor. A few things always use copper wire when you're making the repairs.

Don't take wire from old appliances or old systems. Use wire that is compatible with this. Something that was done. This is a very smart idea, is to keep all the wire nuts facing up. So if there were ever to have ice form in here from a low charge or low fan, or a clogged filter when it melts, these don't fill up with water.

Very smart thing to do. It just prevents disasters in the beginning. When you're finished with this, everything should be wire tied again and look as if no one ever worked on the system. No one should ever be able to tell that you worked on it. So this is a contactor. And when the thermostat goes on, this will pull in like a switch and allow voltage to go to the fan motor and to the heating system.

One or both. This is the transformer. You should just feel this, and it should always be a little warm to touch, so that means that it has energy flowing through it. It doesn't necessarily mean it's good, but usually if they're warm, they're good. If they're ice cold or very hot or burnt up, then of course they're probably not.

Here. You have your heating element and you have a limit switch. Make sure that you read the numbers on the limit limit switch when you replace it and you put the exact same one on in. So if it opens up at 160 degrees, you don't put one that's too high or too low. All of them should be exactly the same parts that you took out.

This should be pushed in, so when you put the cover on, it doesn't crush it. Of course, this is a block that connect the fan and the wire nuts. Now this is the line, and if you look right here. This is where the liquid refrigerant comes down from the compressor and goes into the metering device. And then that metering device takes the liquid and sprays it into like an aerosol mist or puts it into these small tubes.

And as it enters this coil in here, it expands and when you blow air across it. While it, the coil, while the liquid refrigerant is expanding inside the coil, it absorbs heat. So what it feels like is, it feels cold. What it's actually doing is absorbing heat and then it gets blown throughout the home. So these are simple things to, to know and to do.

But you can have, there's a QR code here. Make sure you know exactly what type of fan it is. Everything is mounted securely. Everything should be screwed back down to the panel, so nothing should be put in and just sat inside the um, compartment. And that's a simple HVAC system.