Here we are on a walk-in freezer service call, it's got some ice buildup we're gon na go ahead and open up the electrical panel. I have the management moving some product for me right now, so we're gon na get in here and check out the electrical situation and look at the defrost heaters jumping out of me. So what I'm gon na do is go ahead and initiate defrost the pump down. What a neutral we've got 208, which is correct, you toll and three we've got no voltage neutral and four we've got no voltage actually.

Now that I look closer and if you can see that or not is actually a melt to terminal on number three. So it's not initiating D for us. You look right there. You can actually see some pity here.

I shouldn't say pity, but it's a melted contact and what's happening. Is it's right here we're not making contact when he goes into D for us so they're down there? Moving products, what I'm gon na do is I'm gon na go and replace this defrost clock really quick and then go ahead and fire up the heater. So that way it can defrost while they're moving the product and then once they get it all moved out of the way I'll bring the water hose in there I'll take quick style. I got a new clock here.

You can see right here and that other one I'll show you that that the terminal - that's melted, you'll, see the difference here in a minute. You can see the mountain in there see how it's distorted. It's not making contact. Something, I don't understand is why anybody still uses a flathead screw tries me nuts, if that was a Phillips, fit right on my screwdriver, and I could push it right.

A million dollar idea have someone make this a frost clock with a magnetic top screw, make a lot of service guys happy okay. So this is a basic walk-in freezer. With the basic electrical heat system, 208 volt power goes to one in neutral. At the clock that powers the timer motor and then applies power to the common terminals of the switching relays are switching contacts.

So one in neutrals power notice that one is got a jumper bar right here. Two is your comment for three and four so neutral and four will have power in normal mode, refrigeration, mode and neutral, and three will have power in defrost mode or a switched mode. And then you have a timer release solenoid on X. So that way, if the evaporator coil gets too hot, we have some safety switches down inside of it that will send power back up on the X terminal.

Make this plunger go boom and notice. I just clicked it out of defrost. So that's exactly what it does show you that again so we'll push it in to defrost, so it normal it's in defrost right now, and if we brought power back up on X, this Silla note would sucker this cylinder here would suck this little push rod up Into it and push the unit out of defrost, you can see the mechanical action right now boom just clicked out a defrost, even though it's still saying D for us. So this particular system is a time.

And/Or temperature termination temperature coming up on the X Terminal time using the timer motor this one's set up for a 28-minute defrost. That's pretty typical on these systems that I'm working on got to make sure you change it from the factory to what you need it to so we're 28 minute defrost and I'll go ahead and put my floor. Defrost in there I'm gon na do is I'm gon na harvest the defrost pans of the old block. That way, if we ever run into a weird situation, where you need more than the four we've got extras because it comes with four of them, but I'll leave.

Those ones there extra four some customers want their tea for us to be at an exact time. There's a particular customer doesn't matter just so long as it's nice up, so that really matter. Theoretically, we knew they had a problem on a real busy time going into another box. You might make the defrost not happen.

I just so happens that put them at the same time to the other one anyways just kind of happened by chance. Yes, sir, alright butcher power on pet. So in order to check it, I want to check to see that we have 208 bolts, which we want a neutral. Now, I'm gon na leave one leg on neutral check for knee to the floor.

We have power which is correct, that's refrigeration, but and I'm going to switch from neutral. We should have no power, that's defrost mode! Now, I'm going to twist the timer we're in defrost. Now we have 208 volts going to the defrost heaters and I'll go back to neutral on floor. We should have zero, that's correct, so refrigeration mode is not being powered.

Three now has 208 walls now. Another really important thing in here is, if sorry, if you notice that got two contacts in here well, this is my defrost contactor, and this is my compressor. Contact doesn't always happen this way, but we actually happen to have an auxilary right there that won't let this contact your engage until this contactor disengages. So that's what that auxilary relay is for so I don't know if you notice, but now we have to solve this one pull in and check across.

It got zero volts and I know we've got voltage going into it. So I can simply put my amp clamp right on that wire right. There got 10 amps because that's the defrost heater circuit, so we're gon na, let that run while they're still moving boxes and then I'll start getting my tools ready to defrost that coil. Also it's.

This is a good thing to do. If you're coming out on a nice step, walk-in freezer, it's actually better to check the heaters when it's frozen up because think about it. If I go into there and defrost that coil with hot water and then go to check the heaters well, it might be warm enough to terminate the defrost by sending power up to the ex terminal. So I always say to check it when you first get here.

Come up onto the roof, you know it's iced up, flip it in to defrost and see what happens, because this is the perfect time it's iced up, so that coil is at least 32 degrees right now. So that's what we did! It was iced up flipped it in to defrost found that the defrost wasn't working. You can do it the other way you could defrost at first, but you're gon na have to wait for that coil to get below 20 degrees after you defrost it. So it's just you know you could save a couple minutes by checking the defrost before now.

Just because I see 10 amps on there doesn't mean that every heater is working in that coil, usually there's three to four of them, or maybe even five or six. It just depends, so I just know that my defrost clock is working now. I don't necessarily know that all the heaters are working so that I will have to check downstairs I've actually gotten a pretty good routine. Of doing these, I get a lot of ice stuff.

Workin freezers kind of looks that way that I'm used to doing them and kind of become pretty easy shouldn't, say easy, but I definitely have a routine. You know, I know exactly what tools I'm going to need to bring in here, especially depending on the type of walk-in. If it's a heat craft, I need a wrench to take the fans off if it's a cold phone or a wrestle like this. When I do this, I'm going to take everything out to defrost it, but, like I told you before we're gon na test all the defrost heaters first.

So what I'm gon na do bring over here and show you guys my electrical cabinet pay attention. This is one defrost heater right here for the people that don't know it's not two heaters, so I only need to amp one of these two wires right here, but then there's another defrost heater right here. So there's actually only two total heaters on this unit. So all that I need to do let's check the amperage there's five amps on that one and then just grab this other one.

There's four amps in that one. So all the defrost heaters are working so we're good. So I'm gon na be very careful about this, but I'm gon na leave the heaters running while I'm taking everything apart again once I get to the electrical and the fan whirs I'll shut it off, because unless I can do it safely, disconnect it might as well. The fans aren't going to turn on for the moment.

I mean I guess it's possible - that they could and me personally, I like to completely take out the fan motors fan, blades and everything. If it's a walk-in cooler they're, usually really dirty the walk-in freezers, they don't get as much this one. It's got quick connects, I'm going to be able to get in here. Just pull this thing apart, I'll quit power off, I can't kind of OCD.

So I do things very particular way like to be most efficient sweep from the top down, I'm not focusing on the bottom, because the heat and hot water from the top all the time not letting any water trip out of the pan. If it starts to overflow, you stop the walk-in freezer, you don't want to get water all over the floor, even a cooler but cooler you could walking freezer. Please expand and cause damage waiting for the water to get hot. Hopefully, it's just about give him second starting to get pretty full another journey.

Now a good sign that there's no, no, I, which is why even just the drain nipple on the back you just watching that nipple hole and then making sure it doesn't go too high. On it, and when it does, I just let it drain for a minute. So these are the Linnet switches. Here's one! Okay, here's one! Here's one one! This one has two three: sometimes they just have.

One orders to one of these is gon na, be a fan. Delay one of these is going to be a heater safety and one of these is going to be a defrost termination. At this point, I'm gon na go ahead and assemble everything and then we'll go from there. So I'm back up on the roof.

I got the end all put back together. What I'm gon na do is because, when I got here, this contactor was chattering, really bad. I'm gon na go ahead and replace that contactor, the auxilary relay and the defrost contactor new one I have is gon na. Be a little bit different, but that's the new one that I have snaps onto the side.

You could do normally open or normally closed screws there or screws down here and then it's just a 208 hole contactor. So the action of this basically works with that mechanism. Right there and pulls this thing down, and then, unfortunately, I don't have a single full contact yourself. I'm gon na try to wedge a three pole in there, nice and slow nice and slow.

So this guy correct event civility, and this one just pulled in when this one pulled out, because we so what we're gon na do right now, this thing is set for a 28-minute defrost, we're gon na make sure that the limit switch works. Let it run indeed for us right now was that that course should be nice and warm so so yeah I went downstairs, it's not really something I could show on the camera. The defrost termination switch is bad. So, like I said in the video earlier, you got three switches down there.

Instead of just one that does it all, you've got a heater safety control that just kills the power to the heaters. If, if it gets too hot, that's wired in series with the heaters with one leg, so it just disconnects a leg. Then you have a fan. Delay that turns the fans on and/or keeps them off if the coil is not cold enough, and then you have a defrost termination switch.

The defrost termination switch once the coil gets to a certain temperature. It sends power up to this ex terminal and clicks that solenoid over and that's not happening that coil is really hot right now and it did it's not terminating another way. You could check this too, because I just got done defrosting that coil, so I haven't even turned it on yet at all and after you get done defrosting it. If you put it into defrost most of the times it should click right out via the termination switch.

So I knew something was up right away, but this one has been running for a good 10 minutes on -- mode and that coil is nice and warm should have terminated by now. So, on the switch itself, it's what I thought it was the the top of its swollen out. So I'm gon na go ahead and put this back together. They can operate right now.

It's just gon na do the full 28 minute defrost every time. So, that's probably, why part of the reason why that thing had been getting it's so hot. It's probably just so many amps running through that and it probably had a loose connection. So.