Service calling this delfield unit, the first thing I noticed when I walked up is this: toggle switch is really loose and it's not engaging hold it out, it's burnt and it has voltage to one side, but it doesn't have voltage coming out of the switch. So we're going to change the switch and then further diagnose from there. So I changed the toggle switch and the unit came on. But what I noticed is that the defrost clock I just turned there.

It was saying, like 1:00 a.m. this particular defrost clock in this box, had the battery backup inside of it, so it should never ever lose time so on this particular box. I'll show you the back of this. You know which one it is if it ever loses time it's bad, so I'm going to go ahead and replace the defrost clock also, so I went ahead and put service gauges on this unit and waiting for the thing to come down to temperature about 75 76 Degrees so so far, my liquid saturation temperature is about 30 degrees above ambient.

That's pretty decent. On this box. I have the top section turned off at the moment, so that way we're just monitoring the bottom section. The top section is a cold rail that doesn't have the evaporative fan motors, so the pressures are really different on that.

So when you're diagnosing refrigerant pressures on this box so long as there's not a problem at the top, you want to turn the top off. So that's what I have. The other thing I want to point out is: whenever you can try not to put your stuff on there cutting boards, I put it all up there. There cutting boards are a clean surface and you don't want to dirty them with your dirty tools.

I mean I'm us and I've never done it. Sometimes it happens but try your best so we're just gon na watch. This thing satisfy make sure it works. Sometimes these switches going bad can be just loose connections, kind of what it looks like because it's a burnt-up fitting, so it kind of looks like it might have been loose, but it can also be compressors running hard and this is the weak spot.

So this will heat up or even if it's similar, so we want to make sure that there's nothing wrong with the compressor. Also so many units currently running about 6 amps and according to the name play total load amps is about 12 granted. My top section isn't running, but the only thing that's involved in my top section is a solenoid valve that runs less than an amp, so we're looking good so far in the box, there's already overshot the temperature so keep an eye on it and see what happens So this is the OEM delfield gresling defrost module, and if you notice the QR t uz, I believe it's the QR that represents the little backup battery and it has 150 our reserve. So it'll save the time for a hundred and fifty hours.

I believe of the box being on plug. I believe that's how that works, but regardless I know that if you have this style clock with the QR designation in the model number, it should never lose time for a year. Okay, so just a recap: we had a service call on a delfield refrigerator where the entire box was not working top or bottom right. When I arrived, the first thing I noticed was that the box was not running at all and I first went to the main power switch for the box immediately tried to turn it on and felt that the toggle switch itself was kind of loose okay, so that Particular unit has a history of the toggle switches.

Failing on it, so I went ahead and replaced the toggle switch. I had one in my truck and just started the unit back up and it started running and it actually came down to temperature really quick. I then tried to investigate as to why the toggle switch went bad. The only thing I could find was that the terminal connectors that connect to the toggle switch were burnt up.

So my assumption is, is that possibly we had some loose connectors once I confirmed that there was nothing else wrong, causing the toggle switch to go bad. I finished going through the unit. I did find that the defrost time clock did not have the right time on it and, like I told you in the video that particular time clock is the OEM time clock for that unit. The model number designation.

It is a grassland clock and the model number designation starts with a Q as in Queen Tom University zebra. I think Q t uz yeah and the q tu means that it has a battery backup. So with that particular defrost module or defrost clock, if you ever find it not having the correct time on it now mind you, it has to have that QT uz and the model number designation, because you can go to your normal supply house and buy one that Doesn't have that so don't go out there, just changing every clock just because it has the wrong time. Okay, now on that particular clock, if you ever find that it has the wrong time on it so long as the box has not been unplugged for a hundred and fifty hours consecutively, it should it's bad, basically, okay, so I went ahead and replaced the clock with The factory clock the same one that was in there and then I decided just for the hell of it to go ahead and throw my gauges on there.

And I checked that the box was within what I thought to be the proper operating pressures and temperatures. And it was, the box itself came down to temperature very quickly, okay, but I just wanted to check now as a rule of thumb. I am looking for about 20 to 25 degrees below box temperatures, where your vapor saturation temperature should be, and about 25 to 30 degrees above ambient temperature is where your liquid saturation temperature should be now. Those are rules of thumb again.

I want to reiterate the right way to charge this particular unit is to recover the charge and way in the factory charge. Okay, but sometimes when you're out in the field, you kind of have to make a judgment call. I saw no need to recover the charge because the unit came down to temperature pretty quickly, but I did not feel comfortable walking away from that box without putting my gauges on it again, because once I've touched it even if I didn't touch the refrigeration side, I Own that box, according to that customer, so that's where I've kind of come up with those general rules of thumb on that particular box. That does not necessarily apply to every other manufacturer.

I have just worked on a lot of those little delfield refrigerators, and I know that that's where the pressure should be on that box when it's got the factory charge in it. Another thing to know is that the top section has to be turned off to check the refrigerant pressures. Okay, the bottom section has a standard evaporator coil with the evaporator fan motor, the top section does not. The top section is a cold rail that just has a refrigeration line wrapped around a stainless steel.

Well, the pressures get thrown off when that thing runs. If you ever talk to the factory they're going to tell you to diagnose the box with the top section off, okay so make that clear. The top section was off and I verified that my box temperature, my vapor saturation temperature, was about 25 degrees below my box temperature and my liquid saturation temperature was about 30 degrees above the ambient temperature. Okay, so that made me feel comfortable that the everything on the box was working properly and I just you know, finished it up.

One other thing I want to add to it is that I mentioned in the video I try to think about my customers and I don't want to set my tools on top of their sanitary work. Surfaces. Stainless steel is very easy to clean, but a cutting board that they may have on top of that stainless steel surface is not something that can clean very easily, especially if you get greasy tools on it. So, whenever I work in those situations I like to make sure they're cutting boards are not where I'm going to set my tools.

Okay, that's just like a little hey courtesy. Try to think about the customer! Think about the big picture when you're looking at the box. Don't just go in there and change the toggle switch. Look at everything, that's how I found the defrost module and then, like I said, for shits and giggles.

I put my gauges on there checked it out, found that the pressures were where they should be other than that have a nice day guys, and I just want to say if you guys, I would appreciate it if you leave a comment down in the comment section. Give me a thumbs up if you like my videos and consider subscribing to my channel okay. Thank you very much.