So this morning we have a service call on a little delfield refrigerator, not working correctly they're, saying the top sections temping hi. First things that I noticed on these boxes. You always want to pay attention to is what the temperature controllers are set for. They should be set for number three and when they're set and jammed all the way down to number nine, it's an indication that they were having problems with the bottom two and someone was trying to turn it colder.

This is an older one is to be from 2013 things. You want to pay attention to its how hard it is to move the box. This thing should be on casters that smooth smoothly, and this is moving kind of difficult, so we obviously need new casters. So I'm going to go ahead and pull the back section apart and investigate a little bit further.

So when you're diagnosing these units, you always want to make sure that there's no product on the top or the bottom that way, you're, not fighting warm product and you can actually see what's really going on. The other thing is use your senses. You hear that sound to me that sounds like we're low on refrigerant we're gon na go ahead and gage up. I got my field piece probes on there and we're gon na see what we can find before you troubleshoot.

You always want to make sure you shut off the top rail, so we're definitely low uncharged 77 degrees. We're gon na look for a leak. Two most common places for refrigerant leaks on these delfield units is the compressors suction stub tube and the evaporator coil. When the expansion valve this one looks like there's oil everywhere, so we might already have it figured out what happens is explain it the way that they run the suction line.

It actually creates like a little trap. This suction line comes up and the water sits in that insulation and rots out the suction stub tube and they use a steel, suction stub tube on this you'll see right now you go, I don't even need leak, detector, fluid! You can see a bubbling up. So that's where a leak is will still check the evap too, so the other common place for a refrigerant leak on these is in the evaporator on the expansion valve. So I'm gon na go ahead and defrost that valve real, quick and then we'll do a leak check all on this evaporator coil.

That way we can get a big picture idea if you know there's other things wrong with it. Another thing you always want to watch out is these sensing bulbs. They seem like they've corrected, but in the past they used to strap them with like a little piece of copper tape or whatever, and if they never held. So you would constantly get service calls and it be loose sensing bulbs they've since corrected it and started putting a hose clamp, but I always check the sensing bulb.

If you get an old box, you might find one where you can just move the sensing bulb around and then they have temperature issues as I've talked in other videos. This is a constant cut in temperature controller, as you can see, it's embedded in the evaporator coil. So refrigerant charge is drastically gon na affect the way that this box works, because that coil essentially is going to get too cold and it's gon na shut off early because it's it's, the txb is not feeding correctly okay. So I keep picking up a hit on this leak detector right in this top corner.

This evaporator tip it's like hitting this. It comes, and it goes but there's definitely something going on up in there like picks it up, and then you just leave it up there and it'll go off Nancy. So there's something going on in that coil too. So now we have a better idea exactly what this box needs: yeah, there's no riparian that call it's so tiny in there.

It's just just as quick, just change it out real quick, so we'll submit close to the customer and see what they want to do. For now, I'm gon na go ahead and top off the charge, I'm using the smart probes to charge. This is my setup, a low loss fitting on one side and a valve fitting on the other side, hook the low-loss side up first of the system, purge the gas out and leave it bleeding as you're screwing it on to the tank. Then you know, the entire hose is clear.

Then shut your ball valve and open the tank up. We're going to turn this on we're just gon na, add refrigerant, nice and slow, since we're just topping off temporarily we'll get our liquid saturation temperature about 25 to 30 degrees above ambient right now. It's 86 degrees so 77 in the room. 87.

97. 107. So we need about 100 to 107, liquid saturation 10 and then we'll check. Everything else is just because we're topping it off, and this will get us in the ballpark proper way would be to weigh the refrigerant in again we're doing this with the rail off, because the rail does not have any papper turf ammeter and it's a static pan.

Chiller, it throws your pressure ratings off, so whenever you're charging these things are checking charge. You want to shut the rail off and just have the bottom section running one of the things that will happen here is you will see this thing cycle early right after you fix it, so notice we're 49 degrees in the box. Satisfied! Okay, because what's happening is that txb is flooding right now and it needs to calm down. Basically, so it's going to take about two or three off cycles to stabilize the box out and then, if everything is working correctly, we should see that cut in temperature.

Slowly, come down every time so right now it's probably gon na cut it around fifty fifty two, then the next time it'll probably cut in about forty four forty. You know like that so right now it just clicked back on so so this one cut in at 49 and then we'll watch it and it'll take a couple times. It's because it's a constant cutting temperature controller. That's how they react.

So don't just assume it's a bad control, just watch it a few cycles and to show you an example: I'm currently getting compressor, superheat and we've got three degrees, compressor superheat, and that's just because that TXV is flooding that coil right now so it'll calm down in A few minutes, but it's just the TX abuse, just overreacting, because we just fix the box and all the sudden. It has the right amount of refrigerant, but it just takes a while for it to stabilize that's why it's very important when you make TXV adjustments, you always want to make sure it stabilizes before you start adjusting again, so I just heard it satisfy right now. So this time it's satisfied at 46, so each time that number should go down until it gets typically on this box from 34 to 39 should be the cutout and cut-in temperature of that control. So on that one we had a delfield reaching cooler.

The complaint was that the top section was not working properly. When I arrived, I also found that the bottom section expansion valve was hissing like it was starving for refrigerant. So I went ahead and checked the unit out found that the system was low on refrigerant. I talked off the refrigerant charge to get them operational and then found multiple leaks in the box on those particular delfield regions.

It's very common for them to leak at the compressor, suction, stub, tube and also at the evaporator coil, very common. So that's exactly where I found my leaks. The compression, the compressor suction stub tube usually leaks on those, in my opinion, because of the way that they route the insulation and also because of the way that the stub tube comes out of the compressor. It kind of comes out at an angle and the suction line is ran to the unit and it creates just a tiny little trap and when they insulate it, they slide one single piece of insulation over the suction line, and it creates kind of like a tiny Pietra and that water or moisture sits in that suction insulation or in the insulation, on the suction step, tube and slowly rusts away the suction stub tube, and it's like a little steel, suction stub tube on there.

So they're consistently leaking on those things so anyways there was nothing I could do about that. The compressor needs to be replaced, and then I also found that there was a leak in the evaporator section, and I also found that the unit's casters were starting to go bad because corner of the box was dragging ass. It was just you know, dragging across the ground, so I'm gon na submit a quote to the customer, give them all their options and see where they want to go with this one. I did give them the option to go ahead and unplug the box and just leave it alone, because I did tell them that the leak is probably going to leak out before we can come back and repair it if they approved it.

But they wanted me to go ahead and top off the charge, so I did so got it going and that's pretty much it. Okay!.