This video is brought to you by sportlin quality, integrity and tradition. Today we have a walk-in freezer. That is not working right, so we come into the box. The customer says it's not good.

This is ice cream ice cream is not supposed to move like that. That's pure liquid, so the evaporator fan motors are running. There is no ice on the coils. The coils are free of ice.

So at this point, we need to jump onto the roof, because we need to check out the condensing unit and see what's going on all right so up on the roof. We have a walk-in cooler by the way this one uh was the zoom lock max job. Still looking good um and we have a walk-in freezer right here so as we come up to the unit, it is not running so we need to open it up and uh dive into it, a little bit more figure out what's going on and why it's not! This is our electrical section so, first and foremost we're gon na start by checking three phase power. Now we do have a disconnect switch that does have fuses in it, but we don't really need to open that up.

Yet we can simply check at the three-phase terminal block which, if the fuses are good, we will have three phase at that terminal block, so we're gon na check that guy out real quick. Let's get this guy right here line one to line three. We have 204 line one to line two. We have 204 and line two to line three.

We have 204 so now we have proven that our fuses are good and we are being delivered the proper power to the unit without even opening up the disconnect switch. So sometimes you can skip some steps now. It doesn't mean that we shouldn't open that up just to get a visual eventually, but at this point in the beginning of our troubleshooting, we know that the disconnect is good. The fuses are good.

We're going to start from this point now this particular walk-in freezer is an older system and the condensing unit power controls the evaporator okay. So basically, these wires down here going to four x, three and n, are going down to our evaporator coil. Okay, now process of elimination tells us that between four and n we are gon na have 208 volts, because our evaporator fan motors are running at the moment. Uh n is all the way to the left.

Okay, so we have 208 volt single phase power going down to the evaporator. That means that the time clock okay is sending that power, because the way that this works is power goes into the time, clock and the time clock is kind of like the brain that controls everything. So the time clock is going to decide whether or not it wants to send power to the evaporators and the solenoid valve, or the evaporative fan motors on the solenoid valve and or down to the defrost heaters whenever it's in defrost. Okay, so we know we're sending power downstairs, but our condensing unit is not running.

We need to figure out why. Okay, our evaporator downstairs does have a temperature controller in it, and the temperature controller opens and closes depending on the temperature of the box or the space, and it opens and closes a solenoid valve. Our compressor up here is powered via the low pressure control. So long as the defrost clock is opening the solenoid valve downstairs, or at least sending power down to the thermostat and the thermostat says it's warm in the box open the solenoid.

Then it allows the refrigerant pressure to come up on the suction side and activate via the low pressure control, which is going to be this control right here. So with that being said, we need to figure out why this compressor contactor is not pulling in now. The compressor contactor is controlled via the low pressure control. So if we follow on this schematic right here, we can simply see that on this line right here, this is going to be our control circuit power comes in on wire.

Number 56 goes into the high pressure. Comes out of the high pressure goes into the low pressure comes out of the low pressure, then goes into the compressor. Contactor coil, the compressor contactor coil has one side of power always sitting at it, and the other side is the high and the low pressure control. So we don't have our service gauges up here yet, but we can simply go to our high pressure and our low pressure and check to see if we have any open switches.

So let's do that real quick! So again, if we look back at our schematic, 39 goes into a fuse, then comes out of a fuse and goes through the high pressure, the low pressure and then also goes to another fuse. Those fuses are right here, so let's go ahead and test across the fuses and test to see if we have voltage across the fuses, so the first fuse top to bottom. We have no voltage second fuse top to bottom. We have no voltage.

Okay, now go ahead and test across the top of the fuses each one. There you go all right. We have 208 volts right and test across the bottom just for giggles, even though we know that they're not open okay, so we know that we have power at these fuses. Okay, we have power right here and we have power right here.

So there's a possibility that one of these pressure controls is holding our contactor open from closing, so we need to figure out which one and why that might be happening. So we can step over here to the low pressure control all right. So our low pressure control go across the contact and we have an open circuit. That means that our system is off on low pressure.

Okay, that could mean that the solenoid valve downstairs is not open. That could mean that our system doesn't have any refrigerant in it. That is the question. Okay, so we need to step down to the van and we need to go ahead and get our service gauges so that we can figure this problem out to find out if we're completely out of refrigerant or if our solenoid valve simply isn't open downstairs all right.

We have the joblink probes installed, uh, one on the receiver and one on the low side, and we come down here to the field piece app and if you look, we have 9 psi on the low side. 127 psi on the high side. That indicates that our system is pumped down for some reason why, at this point we know that the system has refrigerant in the high side and with 127 psi in the high side. If the system was open, that would come up on the low side and activate the compressor and make it turn on so clearly that refrigerant is being held back somewhere on the liquid line right.

So it comes out of the receiver after it leaves the condensing unit and it goes downstairs and there's a liquid line, solenoid valve in the way that valve opens and closes dependent on the temperature controller. The temperature controller says: hey it's too warm in here, and it sends power to the solenoid valve or it says it's cold enough and it takes the power away from the solenoid valve. So this indicates that that solenoid valve more than likely, is closing uh down and not allowing this high side pressure to come back through to the low side to activate the compressor. So we need to go downstairs and evaluate that temperature controller and that solenoid valve.

Sometimes you got to think skinny thoughts, so i'm way up on this walk-in freezer shelf. There's our temperature controller notice what it is set for it is set for 40 degrees. Let's turn it down and see what happens. It just turned on okay notice, the damage to the control, and it was set for 40 degrees.

This customer did not adjust this control. This is a flaw of mounting mechanically actuated controls on an evaporator coil that vibrates over time. They adjust themselves. So the customer is not up in here doing this.

There is a little chunk of ice, we'll have to take care of too so we are actually going to solve this problem notice. How the the coil sensing bulb up on the top is kind of damaged too we're going to solve this problem and we're going to install a digital control. So they're never going to have this issue again. We still need to go upstairs, make sure the refrigeration circuit is working, but it is running right now, so we ran it down as cold as it'll.

Go we're going to uh hop up top, make sure the pressures look okay, and if they do then we'll proceed with changing the temperature controller over to a digital control. All right, we come up onto the roof. Now we have suction pressure. We have high side pressure.

We have a condensing unit that is running compressors, running condenser fan motors are running and our sight glass is clear. So i don't see at this point anything wrong with the refrigeration circuit at this point, because this unit controls the power we are now going to shut off. This disconnect switch and we are going to uh um uh. What am i trying to say here? Uh go downstairs and change the temperature controller, so this is our power four downstairs, so we're good to go van's not in the greatest of shape, but i'm in the process of getting ready to switch over to a new van.

So i haven't really wanted to do a whole lot here. So for this situation we've got ke2 controllers yeah. I think we're gon na go with a ronco, etc. 141, it's a nema, 4, 208 or 120 that'll be perfect, and then we just need some electrical fittings which i have over there and some seal type fittings.

So all right, so we got our control um. I kind of have an idea that i'm gon na mount. It right here - and i brought it in to kind of get it prepped um we're going to knock this knockout out we're gon na take the old control completely out of the picture. We do have the electrical terminal block right here to wire into so we'll be able to figure that out so yeah.

This shouldn't be too bad, so we're gon na start prepping. We got two people here, so we will also get rid of this ice before we leave and get it all out of the drain. Pan too um. It's not iced up, though, so i wonder if it was iced up at one point is what i'm thinking but uh yeah we're gon na i'm gon na take the control out of the box and get it all prepped and wired that way, we're not fighting.

You know with electrical fittings and everything in here so to make it easy. I went ahead and brought a black and red for the temperature controller power and then i have two blues for the switch leg, so common and normally open and then we'll make all the jumps and junctions in the coil itself, because we have a terminal block. That way makes it easier to diagnose and deal with this control right here, so we were just talking, and i want to point something out here - that totally makes sense. Look at this fan guard and notice.

What you see see this this is lint lint come over here, it's full of lint. Okay, this is a walk-in freezer. You have to walk through their walk-in cooler to get into the walk-in freezer. There's no reason there should be lint in here other than them consecutively.

Leaving the walk-in cooler door and the walk-in freezer door propped open for extended periods of time, there's so much lint on these that they're doing this all the time. So we did see a little bit of ice buildup as long as our defrost heaters are working which they are because there was no ice buildup on the coil itself, it's just in the side panels and stuff where the heaters can't get to more than likely. This is just because they're leaving the doors open clearly because of the lint all right, we got the control installed in a place where we can get to it. It's secured, we got.

The sensing bulb mounted over here left a little dangle. So that way, it can sense the air temperature, so really it's just time to turn it on and hope that it doesn't snap crackle and pop. So, let's see what happens, i got someone going upstairs to turn the power on right now and there's a meme vibration to this unit. I think we need to get some new fan, blades and fan guards in this guy because something's out of vibration, so it's on 41 degrees, so we got to set it so fahrenheit.

There's our set point. We got to go to negative 10. one. Two, three change that to three: here we go there.

It goes it's on wired it right yeah. This thing is uh out of balance something's going on there. That's why it was vibrating and adjusting up those things they get weak that way too, so we're gon na address this vibration too. I think it's coming from this motor all right.

We let the unit run for a few minutes, and then we popped it into defrost. Okay, so we're testing to see if the defrost heaters are working, four amps on the top heater and five amps on the bottom heater remember: each defrost heater has two sides right: it's just a uh, an element that heats up inside there. So you have to have on, in this case a hot leg. Well, not a hot lake.

You have to have uh two legs of power right because it's a single phase, 208 volt system, so um one of them is going to be going to the n, and then one of them is going to be going to the number three which is going to Be fed via the defrost termination switch, so we don't just ignore other signs. We came in here for a temperature controller that failed, okay, well, a temperature controller that was set too high. We could have just turned the control, but in talking with the customer - and i know what they want, we eliminated this from happening again. Plus the control itself was about to fail mechanically because it was damaged.

The whole sensing element off the top came off, but we noticed that there was a chunk of ice in the top and we noticed there was a bunch of ice in the drain. Pan not stuck to anything just sitting there, which indicates that it was probably iced up previous to that control. Failing again, we could have just changed or turned the control down and walked away more than likely, we would have been back um. You know a couple days, maybe weeks later, because it probably would have done the same thing now: the coils vibrating.

It could be well more than likely you're going to have damaged, fan blades somewhere in there because of the freezing up. Okay, again, everything has a reason that it occurs, fan blades, typically, don't get damaged unless people are in and out of them all the time, if you're in and out taking the fan blades on and off it's more than likely that the coil has been icing up. A bunch, why is it icing up? Well, remember all the lint customers leaving the door open, okay, so big picture when we're doing these repairs, we don't just have a single track. Mind um! Now, if the customer only wants us to do that, then that's fine but they're going to sign off on it too, because we're going to cover our butts in the notes in the invoice.

Another thing that i'm doing right now is: we are testing the defrost termination switch notice. Our coil doesn't have power. Okay, the heaters are running at some point. This coil is going to get warm enough that the defrost termination uh fan, where we have a fan delay and you have a defrost termination, so um this one, i believe, should be our defrost termination.

I believe this one should be the fan, delay um at some point. It's gon na get warm enough in here that the defrost termination is going to terminate the defrost, because i think i put it in like an hour long defrost. It won't last that long it'll pop out in probably 10 minutes, because this coil is warm okay, so we're testing a lot of things as we're in here we're not just ignoring all the other symptoms. You know it's really easy for people to come in and not pay attention to any ice or question why there's ice in the first place right and then, when i walked in here.

There's a new manager at this restaurant - and i introduced myself to him because i haven't met him and he made a comment. You know you guys have been here a bunch of times working on this freezer and i go no and he goes yeah. You guys have been here probably in the last six months, because you guys have been here three or four times we were working on the walk-in freezer door. Right again, they don't understand the concept that the freezer door is something different than the evaporator and the actual cooling system.

So with that being said, sometimes they don't realize that you know you're here for something else. So if you come in just for a temp control and then all of a sudden, you have a failed defrost heater later they're going to say: well, you just worked on it. Well, i did, but i didn't look at that stuff, so eliminate those questions and those potential problems and be thorough. Give them a list of things.

That's wrong with it tell them, there's a vibration. They may not want you to change all the fan. Blades and fan motors, but at least you wrote it down on the invoice and you covered your butt. We are running, but i'm gon na go down there.

Right now being told, looks like the tool is kind of disconnecting, but the cool thing is i'll reconnect. So it's like 25 degrees in the box, so um. Let me walk over here where it's a little bit closer to the evaporator coil. Sometimes when you're down in the box, it has a hard time going through the metal and different things.

So we'll wait for that. There it goes it's back 23., so we are running a high evaporator td right now. So if you see our saturation temperature is negative 15 and we have a 23 degree return. Air temp, a couple things can cause that high td, one of the big things is that this compressor is a big compressor that is sized for high ambient temperatures.

But when it's 60 degrees outside 70 degrees outside the compressor, actually becomes bigger because it's not hot outside. So it's not having to reject as much heat, so the capacity gets bigger and smaller dependent on the ambient temperature. With that being said, because we have a single system with no variable capacity, it's expected to have a higher than normal td when it's not as hot outside. That's one of the flaws of having systems like this now there's other things that can affect the evaporator td2.

If it has a pressure limiting expansion valve a cpr valve um different things like that now, i'm also being told by my service technician. That's downstairs that one of the evaporative fan motors stopped working, which okay so we're going to go down there, investigate that too. You always got to just watch the unit. You know for a little while never just turn it on and run away.

Give it a few minutes of running - and you know, diagnose, go figure huh, so we're going to go ahead and talk to them about putting new blades on both of these, because the coil is still vibrating, so new blades, possibly motor and blade we got to get In here and verify, but i'm pretty sure that's going to be the case all right. We ended up talking to the customer and uh. We ended up changing that left fan motor, but then we were talking to him about the fan blades. We were saying the fan.

Blades are out of balance and they were vibrating and they it's funny the story that you get. They don't tell you everything so they've been de-icing this coil with a butter knife for a while. Now look at these blades. They said that oh yeah, it keeps icing up and we just take a knife and chip away.

The ice look at how damaged these blades are so uh you've always got to ask questions and they don't always. You know, tell you everything from the beginning. Have a conversation and stuff will come out in the conversation, that'll really kind of guide you into where you're going so we're changing. All three fan: blades the left motor, we're going to turn it on and test to make sure everything else works properly.

All right! It's running now it's still slightly vibrating. So that's one of the downsides to these aluminum blades. Is you kind of got to tweak them sometimes so we're going to turn it off, but it's much better. It's not as bad as it was so everything's good.

We left the guards off purposely because we thought we might have to tweak them a little bit we're going to turn it off, adjust the blades just a teeny bit and then put it all back together, all right, everything's back on. We are uh, basically wrapping it up. We're gon na have to watch the box come down in temperature before we can evaluate the refrigerant pressures anymore. The pressures are still really high.

We reduce the vibration, it's not completely gone, but it never is. Those fan. Blades are not the greatest things in the world, no matter when you buy them, they're, always a little out of balance um but yeah all is well we'll tell the customer to keep an eye on it and, like i said we'll, do a verbal follow-up tomorrow. Make sure everything's all right, so this is a typical walk-in freezer evaporator circuit and where there's a major flaw in this circuit and the way that the schematic is drawn.

I actually experienced this flaw and i wanted to kind of visualize this and make it make sense for everybody as to why this is a flaw. So i'm trying to install a digital temperature controller. The schematic specifically tells you how to wire in a digital temperature controller. On this circuit, so what we're going to do is we are going to draw it out and i'm going to explain why this setup will not work okay.

So, let's draw it out. First off we have power. Coming in on n, okay n is going to come in it's going to go down. It's going to go to your fan, delay switch okay, the fan delay, switch closes on fall, so the drop in temperature closes.

The fan delay switch line. Two or in is going to come in and sit at the liquid line. Solenoid valve and sit at the fan. Delay switch right until the evaporative coil gets cold enough.

Then the fan delay, switch, will close. Okay and the fan delay switch will then send power to h4, which will then in turn send power to line two or the common terminal of the digital thermostat. That is the power that gives the thermostat power to turn on okay, so we're going to come over. Come over, this is a 208 single phase circuit.

Then it is going to turn on the evaporator fan motors. Okay. Now, let's bring in our other leg of power line, one coming in on four line: one goes directly to the fan motor. So, whenever we are in refrigeration mode, we're sending power to one side of the fan motors and then we're going over here, we're sending power to line one of the digital thermostat.

That is going to power it on and turn on the display, and then we're also going to take power over to the c terminal, which is the common on the dry contacts. Now, if the um thermostats logic tells the system that it is warm enough in the box, then it is going to close the normally open terminal and it is going to send power right over here to the liquid line solenoid valve and the liquid line solenoid valve Is going to energize, the compressor is going to turn on and the evaporator is going to start getting cold, but i jumped over a very, very important flaw in this setup right here, all right now: let's do it again! Okay! So let's draw that again line. Two comes down goes over to our fan. Delay switch goes over to one side of the liquid line, solenoid valve and then that's it.

Okay, then we're gon na go over here to line one coming off the number four terminal. It's gon na sit at the evaporator fan motors, just waiting right and there's a reason why this happens and it's going to come over here, go to one leg of the digital thermostat and sit at the c or the common terminal of the dry contacts. Okay. But here's the flaw if our box is very high in temperature, the fan delay switch right here is going to be open because the purpose of the fan delay switch is to not turn the evaporator fan motors on right away when the system starts up okay, so It does that the theory is, is that the compressor turns on the evaporator gets cold enough.

It delays the fan starting up so that we don't blow steam and moisture off the evaporator coil. We typically get the coil down to about 20 degrees and then boom. We can turn the evaporator fan motors on so think about it. What i said was the line two of the thermostat is powered.

According to this schematic from the fan, delay terminal or the fan delay switch. It can't be that way. Okay, so what i had to do was run an extra wire over directly into the digital thermostat. So now coming off of the in terminal line, two we have power going direct to the digital thermostat and we can wait for the fan delay because the fan delay is now only going to control the evaporator fan motors.

So the compressor turns on. We go right here. Liquid line, solenoid valve gets energized, because now the logic in the thermostat says: hey it's warm in this box. I can't stress enough that you, you need to take your time.

You need to be thorough. You need to dig into everything. Okay. Now i didn't get good footage of it, but at the end of the video i showed you guys the problem with the schematic.

What actually happened - and i don't know why i didn't get footage of this. But what actually happened was we turned the unit on? You guys saw that part when we turned on the power the thermostat digital thermostat came on solenoid valve everything started running when we put the unit into defrost and we turned it back on after defrost, the thermostat. Wouldn't turn on and we by putting it in defrost, we brought the temperature of the coil up significantly and that in turn made the fan delay open up. So therefore, when it came out of defrost, we tried to take it out of defrost.

It wouldn't turn the digital thermostat on again and that's when i ran into the problem, because i followed the schematic and wired it up according to the schematic, when i put the digital control now. Another thing is that if you go back to the very beginning of the video, if you look at that mechanical thermostat right next to it is the remnants of a digital bulb. Okay, there was a bulb for the thermostat, and that bulb clearly indicates, and the schematic indicates that this was originally a digital thermostat and it was converted to a mechanical control. Okay.

So when i was trying to go back in with a digital thermostat, it worked at first and then we found the problem, and this goes to show that you need to test your systems after you replace components, you need to test all the functions to make sure That you don't run into any weird problems, because this would have been a callback the first time it went into defrost that digital stat would have never came back on and someone would have had a hard time trying to figure it out and again. If someone that didn't understand exactly what was going on in the system - and it was just following a schematic - they would have been like it's wired. Fine, i don't understand right, but you have to be able to visualize things in your head and say wait. This doesn't make sense, you know just looking at the schematic and it took me a minute at first because i wired it according to the schematic.

You know just like oh yeah, easy peasy, you know, and then i didn't think too much of it. But then, when i was testing the system after that's when i noticed the problem - okay, also, the vibrations and different things like that, the managers chipping on the ice, like all that stuff is just so funny. But that happens in restaurants all the time, especially right now, because we have a really high turnover rate for employees in kitchens, whether it be kitchen staff. That's why doors are being left open so much because they have new staff in the building and that new staff is causing problems because they don't know proper procedures, and i get it you know but kitchen staff's like well.

I got to go in and out of the box five times to put all this food in there. Why not just prop the door open, so i don't got to keep opening the door, but that's not how walk-ins work right and these restaurants don't want to go with fancy uh. You know air curtains or anything like that. They don't even want to use plastic curtains.

So you know they got to keep those doors shut, but always take your time go through things test, your your systems after you replace components and different things, and try to look at the big picture. Use your senses as i always talk. Okay, i really appreciate you guys making it to the end of the video you guys are amazing. It's very humbling to have all the support.

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There's a lot of animosity a lot of fear, a lot of confusion, a lot of misinformation and uh people get their feelings, hurt way too much and um. You know you never know what someone else is going through uh, not justifying people being idiots or anything, but i mean still you never know what someone else is going through right. Most of you guys don't know that i deal with anxiety and depression, i mean. Maybe you do if you watch my stuff, because i try to be as vocal as possible, but i don't know if it comes across in my normal videos right so i mean there's always something going on with someone.

Okay, so you know. Sometimes people make mistakes. Sometimes people aren't nice whatever. You know just remember that and keep that in mind.

Okay, again, not just to find anybody being a dummy, but just keep that in mind be kind to one another. Okay, i really appreciate you and we will catch you on the next one: okay.