In this second clip of the series on the repair of an Amana air conditioning unit, our Nate-Certified Service Professional quickly identifies the parts that need replacement in this rooftop unit. Jacob goes quickly through a checklist of electrical tests designed to make a diagnostic of the unit: he measures the electrical and magnetic outputs of certain components, and visually inspect the corrosion of electrical terminals. This short video will teach you more about your A/C unit than a lengthy (and boring) owner’s manual.

“Ok, so here we are at the unit. Now I’ve already disconnected power and I’ve already completed my inspection, but we’re going to see what’s wrong with this unit. First off, what we all do here at D&H AC as part of our service and our inspections is that we always check the electrical components. First thing I check is my current controller here. I’m going to use my electrical meter and I’m going to see how we’re doing, how we’re rating. You notice here on the side of the current controller it’s rated for 45 for the compressor and 5 for the outdoor fan motor and that can be within a 5% tolerance of those numbers. Anything out of those tolerance is no longer acceptable by the factory and I recommend immediate replacement on that.

Let’s go ahead and and check the compressor site of this air conditioning unit. My meter tells me it’s about 43/42.9, that’s still within 5% that’s ok. Let’s check our fan side: 4.3 hmm rated for 5, it can be as low as 25% of 5 which is 0.25 so it can be as low as 4.75; 4.73 is quite a bit lower than 4.75. I’m going to go ahead replace its capacitor on this current controller.

Another thing that we always check is our main line compressor starters. Now the main line compressor starters is what allows the voltage to pass through in order to get to your compressor and your outdoor fan motor. This is controlled by a low-voltage signal coming from our thermostat here on the sides. So now what I’m seeing here is I’m looking at the inside of the contact right there and I notice, you can see it, it’s pretty burned out. It’s got a lot of pitting going on the contact. Now what that means if we have too much pitting going on there’s not going to be a flat surface in order for those contacts to sit on. Now that means we’re not going to have a good enough electrical connection and it’s going to cause your motors to work harder because you don’t have a strong connection anymore. And what could also happen it could also weld itself shut: it’ll stick itself close and will not open up anymore and the only way to turn it off would be at the breaker. So once it’s at this state towards burned and pitted like that I will definitely replace that, I recommend for it to be replaced. But since everything is under a 10-year parts and labor warranty I’m going to go replace everything anyway.

Now let’s take a look here at our current controller for our fan motor, our blower motor. So we’re going to stick our meter in there, probe is in there. Now this is rated for 10 microfarads and we can see here on my meter its rating about 8.5. Now this as same as the other one it can be a 5% tolerance. So it can be as low as 9.5, 8.5 is quite a bit lower than 9.5. I’m going to definitely that to be replaced as well.

You can also see there’s quite a bit of rust on the side of the current controller and there’s some oil leaking out there too. That’s another sign that it’s about to fail. So those are the three things that are going to have to immediately be replaced.

Now takes take a look over here on our other side of our air conditioning unit. Now this is our evaporative coil or in other words our cooling coil and since this is a heat pump this coil is actually used as part of our heating system as well during the winter season. Now you can see here on this coil there’s a lot of dirt on the fans and that’s plugging up your coil. Now the reason I check this is because the first thing I noticed when we came to this call was that we had a plugged filter. Plugged filter since it can no longer hold anymore dirt, that dirt is going to get sucked up into this coil an cause issues for you unit as far as efficiency goes. This coil right here I would say is probably be anywhere from 20%-30% plugged. Now some people may say that’s not really that much, well that 20%-30% loss of efficiency that you are getting during the summer. Now how’s that going to reflect in your electric bills right? It’s going to be pretty significant. So I’m going to definitely recommend that this gets clean. I’m going to go ahead and do these repairs now.”

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