This video is brought to you by spore'ln quality, integrity and tradition. I mean a service call that this. This is like a hybrid cooler. Freezer was temping high, they got a delivery and they loaded it in.

But then the fans never came back on so we're just gon na kind of go through everything when I walked in the door it's running and their thermometer, whether or not it's accurate is saying 25 degrees and that's about correct because I think they run in at About 20 degrees 15 degrees - something like that. So so visual inspection shows me that the evaporator is a little dirty. It's not horrendous, but it's got some lint on it. So I'm gon na give it a quick brush before I go up onto the roof and I went ahead and put my spark probes in here: get the super heat and everything and then I'll take the high side probe and the air temp probe up to.

So I'm gon na brush this real quick. Just it's not horrible, so I think it's good so I'll just give it a quick brush and we'll jump on the roof. As I was leaving the walk-in, it's satisfied. I could hear it so I come up onto the roof.

I have a feeling what's gon na happen here is that the unit was in a defrost because they called me about an hour and a half ago, and it looks like it just came out of a defrost, but on top of that, the defrost is too long On this guy, this is a hybrid walk-in cooler. It's got a freezer, coil shouldn't be running a 45-minute defrost and I bet you anything there's something going on with the limits, which is because it should terminate defrost too. If it goes too long, but but anyways, we need to shorten that. There's no need for a 45-minute defrost off of that.

You only need a half-hour defrost in our area, and you know we'll just check everything else out. Condensers, look really dirty! So we'll give these guys a clean all of their condensers look dirty! So alright. So I got the disconnect switch shut off a verified power. We're gon na give this guy a quick rinse from the front, try not to blow it in kind of dirty and then we'll give it a rinse as best as we can from the inside out.

I went ahead really quickly and hosed off all their other equipment to that other condensers and stuff. I just gave them a quick codes, nothing too and then we'll get it from the inside out. Like I said, if I can, I don't, I don't think I can sell hope have to give it a good one from here now, without taking up a fan motors, be careful not to saturate the motors you can either they don't short out everywhere. Second, Coming 30 point and it was just surface stuff the same on the ACS yeah, I'm gon na recommend that they have us come back and do a proper cleaning on the AC units, because that one on the inner coil is really dirty.

But yeah. We can do all right I'll, let this dry out for a sec, Pat it down normally just kind of Pat down most of the water and then we'll. I start it up all right. The fan motors look slow just because the frame rate of the camera they're working properly, so one thing I will say is we are running lower than normal head pressure right now, because our condenser is wet and our sight glass is flashing.

This unit can use this condenser flooding. We have a head pressure control valve right there. The bypass pressure is 180 psi. Sometimes it takes a minute for the condenser to fill up with liquid, but this one has been flashing for quite a bit of time now.

Normally, I wouldn't say, wet the condenser to check the charge, but in this situation I had to and we're definitely not and low, because we're running about 177 psi. So we should have a clear sight: glass right now: don't let it run for a few more minutes see if it continues to do that. That could be something too and we'll check everything else off, so we're just gon na let it run alright. So we are still running with a flashing side, glass and again.

This is not a good way to do this, but what I did is I have a mister keeping my head pressure right below the bypass pressure of the head pressure control valve. It's not really good method to use that unless you are very careful about this, because you know the fear is that you can overcharge a system. You don't want to saturate the condenser to the point that it brings the the condensing temped a low lower than a point that it'll ever be and then potentially you could overcharge the system. So you don't want to do that unless you're very careful.

So what I'm doing here is just using a mr. to keep the condensing Tim dust below, because I just wanted to know if it really was low on gas, because sometimes it could just be flooding the condenser, and it takes a few minutes for the sight glass To clear up so in my situation we can test it. My discharge line is warm. Liquid drain is cold, liquid line is warm, so it's partially bypassing it's not fully bypassing just partially and keeping the condenser a little bit cool and we're still flashing.

So in this situation, I'm not going to charge it with the water. This is just helping me to verify whether or not it was low uncharged. This is a micro channel condenser. Basically, if you talk to heat craft, which is the manufacturer this unit, they do give you a calculation on how to figure out the flooded charge.

But when you call tech support, it's it's it's so confusing that tech support just literally tells you to put the maximum amount of refrigerant in the system. This unit - I don't know on other units. I know the maximum charge this one - I don't know so. I'm gon na have to do some research and then I'll probably end up just pumping the system down and filling up the receiver is what I'm probably gon na end up doing.

Another thing I want to point out to micro channels are a little bit different than standard tube and fin condensers, and if you actually saturate the entire condenser, you can drive the head pressure up on a micro Channel and I'm kind of showing you that a little Bit right now and my head pressure went up about one PSI, but if I turn this hose and saturate the condenser you're not going to get as much of the evaporation effect as if you were just misting it you know lightly. Basically so, let's see if I can drive this head pressure up to show you guys so I'll put it on the shower mode and be careful cuz, I don't want to short out a fan motor. Let's just get it wet. If we can't drive this head pressure up notice how the head pressure went up to 180 183 184, that's because we're saturating the condenser to the point that it can't breathe anymore and we're actually driving the head pressure up.

Now, as we pull the water off, the evaporation effect will start happening and you'll start seeing, but look at at one point: we drove the head pressure all the way up to 190, so it's very easy to saturate a micro Channel because of the small little openings For the air to pass through and in fact in the summertime, if you guys have ever seen it on like a 410, a condensing unit or air conditioning unit, you can actually trip the high head pressure control by turning it on right after you cleaned it. So that's why they tell you to tap the condensers, so it's going to take a few minutes for the evaporation effect to kick in or I can just simply start tapping getting the water out of it. It takes a very long time for the water to come out of a micro Channel. So what I can do is turn this back down to mist and then we can just lightly mist it and we'll start dropping the head pressure again very interesting.

The whole dynamics of a microchannel and there we go we're dropping the head pressure down one 79.5 again, it's kind of a trip how it works, just just light mist, letting the evaporation effect hell or work a little bit better helps with the micro Channel. So I'm not using this to charge. I was just using this to verify that once we started cooling down the condenser that the sight glass would continue to flash, because the unit was satisfying too soon, so I've propped open the door and we're just letting it run with just slight mist going across the Condenser keeping us below it's one. Seventy nine point two and I can go down here and pot discharge line cold liquid drain warm coming out of the head pressure control valve, so we're feeding warm or hot vapor into the top of the receiver, and the problem is, is that we don't have a Proper, liquid seal and our sight glass is flashing.

We are also running rather high superheat, and this is evaporator superheat, so we're gon na go ahead and you can see it's kind of frost enough coming on the coils, not frosted up, though so we're gon na go ahead and bring the superheat down by bringing the Stem out of the valve down we're gon na go with mr. berry, barely any terms. So that's one full turn and we're gon na see what that does and let it run for a little bit. It's coming down.

You got to give it some time. They've had some other people working here previous to me, this is a new customer to me normally I'd say: there's a problem, but I wouldn't be surprised if someone's been wrenching on this valve and didn't know what they were doing so we're gon na go ahead and Get it dialed in and then give it a shot and see if we have any other issues with it. So there is something wrong with the valve after all, because I just adjusted it a little bit more and the valve won't ajaan. It's basically open all the way, so there's a powerhead issue or a strainer.

That's plugged up something like that. Probably a powerhead issue with the tightness of this valve, I'm not gon na change. It's not power head. I change the whole mouth we'll make the recommendations.

They're gon na be fine and operating and made a difference where, from 30 degrees, superheat now down to 16, so it's better than it was ideally we're. Looking for 8 to 10 degrees on this unit, so suction pressure went up a little bit, that's good too! So better than it was and we'll submit a quote to replace the expansion valve and then when we do that, we'll recover the charge and weigh it in properly. I went ahead and cleared the sight glass for now. What I did was.

I went ahead and before I added any gas I went ahead and pumped down this receiver and checked the refrigerant level all was pumped down. The refrigerant level was half a receiver. What I did was, I found the paperwork for this condensing unit from heat craft and again it's very confusing. But if I'm reading it correctly, it says that the winter charge is half a pound which makes sense, because I know in these micro channel units they take bounces literally to be the winter charge.

You got to be careful about overcharging himself. I went ahead and added half a pound of refrigerant to this unit. Again, it's kind of a guess: okay, because even when I talk to heat craft, they don't have a definite answer on how to figure out the winter charge. Typically, in the multiple times I've called them.

They always tell you just to put the maximum amount of refrigerant in the unit that they list as their maximum charge for the unit, and they tell you to call it good at that. So I am gon na call them again and go through this and see if I can get someone that explains their winter charge a little bit better to me, because it's not like the normal spoil in 90 30. One method because that's on a tube and fin condenser, but this is a micro Channel. Okay, so again my logic was I pumped down the receiver.

I knew that it wasn't varied that the liquid level, when it was pumped down, was halfway. You never want to go over 80 % charge, which would theoretically be 3/4 of a receiver. So all that I did was added a half a pound, it's kind of a guess, okay, but I think that's gon na solve it as usual. Big picture diagnosis when downstairs check the evaporator superheat, because I noticed my suction pressure was a little bit low on my gauges.

According to what measure quick said, my target should be I'm looking for about a 10 degree. Evaporator TD - and we were really low, so went downstairs, found that the expansion valve was frosting and the superheat was really high, adjusted the expansion valve got the superheat down to what 16 degrees or something like that. But then the valve would not adjust anymore. I pulled the stem completely out, I mean you know as far out of the valve as I can in it, and it stopped so there's something going on there.

More than likely it's gon na be a power head issue, or something like that. This unit does have an MLP charge or a pressure limiting power head. Those can be a little confusing too, but anyways I'm going to submit a quote to go ahead and replace that expansion valve now. If it was an easier valve and there wasn't so much stuff in there, I would try just changing the power head.

But in this situation it's so tight in there, I'm just gon na change the valve - it's just gon na be easier, but normal operating procedure would be to pull the strainer pump. The system down, pull the strainer, see if it's clean and then change the power head. Usually that fixes the expansion valve problems because usually there's not much inside the valve that can fail. But in this situation I'm probably gon na go and replace the valve.

When I do that in my quote, to change the valve I'll recover all the refrigerant and then I'll find out the maximum charge and I'll make sure that I quote for the right amount of refrigerant, it's possible that this unit was never charged correctly. Who knows? Okay or it could have a leak I'll, definitely look at the evaporator too, and we'll see it when we pull a vacuum and all that good stuff. Initially, I think my initial call on this unit. I think the original problem was that they had gotten a delivery.

This morning and the manager noticed when they were done, putting the delivery way that the condensed that the evaporators didn't turn on it was probably just in defrost because it had those 45-minute defrost. That's the other thing too. I need to look at before I leave was why didn't it terminate because it should have terminated on temperature unless someone disconnected the termination down there with very common, especially on these hybrid walk-in coolers, because they maintain about the manager set 28 degrees in the box. So a lot of times the defrost termination switch is the coil won't get warm enough, basically to terminate defrost so anyways or or because they run the higher temps.

I should say the coil will terminate defrost every single time. So a lot of people don't hook up the terminations. Now there is heat, Kraft does offer a different termination switch. Then what comes with the coil? If you're going to be running one of these weird hybrid ones - okay or if you happen to throw a electric heat on a medium tempo, they have a special termination switch.

So we'll look into that. That's where we're at pretty much real quick. I went to go set the time on the defrost clock and I think it's barely even moves. It's all gummed up with sand, so that could be part of the problem too, even though it has the right time on it, it's possible there's something going on with that, so the gears are all gummed up with sand.

So we'll put a new defrost clock in our quote, like they're gon na get a little bit everything on this. Alright, so we're back here today and we're gon na go ahead and replace this expansion valve, and I noticed that I don't know why. I didn't notice this last time, but there's oil all right here, very common for them to leak at the Schrader's, and I noticed this Schrader seemed really loose and let's see it's picking it up. Alright, there so we're gon na go and recover the charge and we'll replace that Schrader valve.

When we do so we're gon na go ahead and recover the charge, we've got the tank open. I purged to the tank before we turned it on field piece machine on everything's, open scales, zeroed out right here, so we're gon na go ahead and hit start open it up. We are getting ready to put this new valve in. We got it wrapped in some wet rag, just kind of fitting it and then we're gon na braise it in real quick.

So you shouldn't be too difficult, so we've got the valve protected with wet right. We've got someone here helping me today, so we're gon na be able to it's going to try to fall down. When I try to do the top grade stuff. We've got nitrogen flowing through this system too.

No boys a little heavy on my solder kind of lying weld, I'm assuming it took in the back when you go ahead and do this one real, quick, I'm currently doing a nitrogen pressure test. We went ahead because we saw that leak. I went ahead and cut that Valve out because it was actually leaking on the top. I hate doing that because you lose the ability to change the compressor without recovering the charge, but it was just you know.

I'd rather be taken care of so I actually went a little high on. My pressures should be. Okay, though, usually don't want to go that high. I guess the important thing is.

Is that the evaporators not that high nothing again, there is a syllabi down there. So the evaporator should be equalized, you know and I'm a little confused. It should be equalizing. That's weird love I have a guy downstairs, so maybe the magnet came off or something because the solenoid magnet should be letting the pressures equalize all the way through.

We verified that the solenoid magnets still on that is really weird that my pressures are not equalizing out huh. I do not have a pressure limiting power head on the valve anymore, so shouldn't have anything to do with that. What is going on here? That is really weird. It wasn't a true 300 psi.

I don't know what happened there. I must have shut it off soon or something it got trapped because I equalized the gauges out and it didn't take very long at all and it dropped down to 180. So yeah that was weird. I don't know what happened but anyways, so we're just gon na do a standing pressure test.

I mean. Theoretically, I can go ahead and hit the tightness test. I don't have that suction clamp on, but it's it's looking at the suction pressure and timing it. So we can see what it drops, but there's gon na be a bit of refrigerant in there too.

So just because it's still in the oil but alright we're gon na. Do that and then we'll get the vacuum running. I know I'm not giving it the full amount of time, but it actually started like at 0.5 from the beginning. I it really hasn't even dropped in 6 minutes.

I'm not worried about it. We're gon na go ahead and dump this nitrogen and get the vacuum rig going. Did this thing evacuating? Okay, I'm pulling down with the vacuum with the true-blue hoses and the field piece vacuum pump. I really like them.

They do really well. The micron gauge is attached and I have them pulling from both sides right now, because I want to get the system down in pressure but just understand the location of the micron gauge and the valve core removal tool being open. This is a lower reading than what's truly in the system. I would get a real reading if I valved off this view, CRT the vacuum core removal tool.

If I dialed it off, this would still be reading the system pressure and we would only be pulling from the low side. So you would get a very true reading, but I'm trying to get this system down in the low microns. You know as quick as possible. Once I get into the thousand range I'll close the gas ballast, you can tell on the field piece pump by the red light, so I'll close the gas ballast.

I have new oil in there because I actually just cleaned out my van and change the oil last night. I went ahead and close the gas ballast. I really like how the light disappears to let you know so you don't forget we're pulling down kind of sucks, though, because gon na rain storm coming and it's drizzling on me right now. That's how it works so we'll see what we can get to the field piece vacuum pump can handle water.

The only thing is is that if it's a torrential downpour the - I think it's through the the GAT, the exhaust, you can get water into the oil. So that's the only thing, but they have a built-in. I mean the water would have to get above this level to get in there. So, like I said, if it's a torrential downpour it'll get in there, just put something over it.

That's all idea, but I don't expect like a crazy, downpour right now, cool thing that I do like about this, though, is they purposely put a hose thread on there, so you could actually hook up a garden hose to this and, if you're, in a place where You don't want to be putting all the refrigerant vapor exhaust from the vacuum pump like a medical facility or something you could exhaust it out of the room or something like that. So it's kind of a cool feature. We are running we're still in a vacuum, but I turn power on energized to solenoid. We had a solenoid, coil or so inline magnet on there, but now we got the actual valve everything's put back together.

We ended up changing the thermostat to because it was all rusted out, so we just got ta wait for the evacuation to finish. We went ahead and mounted the sensing bulb on the back wall. That way gets a true reading, so we're just waiting for it to evacuate this evacuation is taking longer than I'd like, and this is one of the reasons why I'm not a fan of using nitrogen, unless I absolutely have to now this situation, I wanted to do It because I was looking for a leak and I wanted to pressure test the system, but I haven't released the video yet, but I actually have a video where I proved that nitrogen can also get stuck in the oil. I know a lot of people say that it can, once I release the video you guys will see that the test is pretty obvious, that nitrogen can get stuck in the oil so what's happening here, though notice that my micron levels are 1213.

So what happens? I have refrigerant and nitrogen in this, I'm going to shake it, look at how it jumped that's, because we've got nitrogen and refrigerant vapor, that's trapped in the oil and it's boiling out now I've already energized the power, so the crankcase heater is getting hot. But what you can also do very carefully this one's a hermetic compressor, so I can just heat underneath there's no wires on the other side that are getting melted and we can watch will start climbing. Once I start heating up the oil there at 1264 1263. Give it a minute, 12, 65, 66 C, because I'm boiling the non-condensibles and the moisture out of the oil - and they were perfectly we're not going to obtain a perfect vacuum here, because I'm also trying to beat this rain.

But uh. Had I not put nitrogen in it, I wouldn't be so worried because it's just in my opinion, refrigerant vapor. Now, if my vacuum was stalling out again, I'm not a genius when it comes to evacuation. But logically, if my vacuum was stalling out and if I shook the compressor or i heated up the oil and it didn't raise the micron levels, then I would assume that maybe we have a refrigerant leak.

But I don't think we have a refrigerant leak because we did a pressure test it held. I granted. I only did it for six minutes, but it held, and I went ahead and change the oil and it started pulling down a little bit faster and whenever I shake the compressor, it rises. So that tells me that it's just things boiling out of the oil, to be honest - and I've said this before you know, pulling a perfect vacuum, isn't always practical when you're dealing with refrigeration, I mean.

Obviously, you want to try to do it as best as possible, but I've got a walk-in, that's at 46 degrees right now, and you know we so long as we don't have a leak. I'm gon na have to open this system up because I can't have health inspectors walk in and see their food now granted their food temp isn't at 46 yet because we just shut it off this morning, but the air temp in the box. So it's slowly absorbing into the food. You know you can't always get a perfect vacuum, especially on refrigeration, especially on old systems, and absolutely if you have a pump down system now, this isn't a pump down, but everything leaks on these systems.

You know that's why it's uh -- cz, that I put nitrogen in this, because now it's like how much of the stuff that's left in there's nitrogen and that's a non condensable. You know. If it's just moisture, you know we could hope that the dryer pulls some of it out but and and theoretically you know, you're not gon na get all the moisture out of the oil if it is, but so we're gon na have to go ahead and let This guy go I'm doing a test right now. It was down to about 1100 microns, I'm isolating it and checking it, but we're gon na go ahead and disconnect everything and get it back up and running because I got to get this customer operating.

You got to be practical, the box has been running and it's pretty much down to temp and we just came in here and our super heat from the factory was out about 16 degrees and we went ahead and wrenched on the valve and opened it up about A turn and a half and we're just gon na, let it stabilize out, I'm probably not going to adjust it anymore, but we got it down to nine degrees, so we're just waiting for the box come down to temp and we also adjusted the thermostat colder. We're looking for about 20 degrees box, then it's about 25 in here right now, so all right, that is, where we're gon na leave it there about 8 degrees superheat and it's still kind of moving a little bit I'd say we open the valve about two and A quarter turns, I think, which normally you shouldn't, have to adjust these valves, but this is kind of like one of those hybrid boxes, so I'm sure that has something to do with it. Normally a walk-in freezer is negative, 10 and technically. This is a freezer coil.

So it's just that weird thing but yeah. I think we're going to call it good at that. Our expansion valves now basically responding the frost pattern, looks nice and even happy with that. We put a new thermostat in and it's cold in the box.

So the last thing we're gon na do is watch it come down in town all right. This thing is actually satisfied. Now I came up here, though, because I want to wait for it to turn back on and then we're gon na. Do a final leak check.

Just to be safe and you can see that we actually filled up the receiver and we marked it with the date right there. So that way, people know that the bolt charge is at the receiver level. Right there. I got new caps everything's, you know we installed the filter dryers, so it's visible from the front of the unit.

Yeah everything's, looking good, so last thing we're gon na. Do it got my leak detector up here as soon as this thing turns on we'll do a leak test on everything we'll go downstairs leak check the evaporite just to be sure it actually had gone in to defrost? I didn't mention either that I went ahead and replace the defrost clock and took care of that too. So shorten the defrost, because this isn't a typical walk-in freezer. I'm only gon na do a 15 minute defrost about here here here and then in the middle of the night.

We had a service call. You know, like I said in the beginning of the video on a walk-in cooler, slash freezer. They run like 25 degree box. Tenth inside they're, not working and initially you know, I really think that it was just the defrost clock.

But looking at the big picture I saw that the unit had a flashing sight glass and then I, when I went ahead and put my gauges on it. I went ahead and checked the evaporator superheat. We were running kind of low suction pressure, found that the superheat was extremely high, got no response from or not very much response from adjusting the valve, so pretty good odds that there was a problem with that valve. My thoughts were that it was in the powerhead.

I have the valve well, actually dissect it. Maybe I'll show it on a live stream or something like that and we'll take it apart and figure out exactly what happened to it, but went ahead and quoted it. It took actually like it took him like a month almost to approve that quote, so it seemed like silly how long it took but anyways finally got it approved and win it back out and replaced it recovered. The gas found a leak at the discharge line service valve.

You know I showed in this too the evacuations guys. I've said this before, but you know sometimes it's just not practical and it's not feasible to get a perfect vacuum. You you've got customers that want their equipment running and you know bottom line, they want it working, they want it working as best as possible, and sometimes you got to do what you got to do you know, so I couldn't obtain a perfect vacuum in that system. I tried my best, but you know with the time constraints I had in the system being at 46 degrees and their food still in the box like we had to get it running, so we went ahead and started it up, we'll monitor it.

You know if I notice any other issues, we may you know, go back in there and do a better evacuation. Maybe pull the charge. I don't know you know it just depends. We'll have to see what happens.

Maybe we just go back and change the liquid line. Filter drier, but for that one this is it everything was operating properly. I didn't see any signs of non-condensibles, so if there was something in there, it was very my knew you know so you just sometimes you got ta understand that you can't always. You know, pull this perfect vacuum or you can't always braise with nitrogen.

We try as much as we can to follow proper refrigeration practices, but sometimes you know things just don't work out the way that you plan them and you got to do what you got to do right. A couple things number one. Thank you so very much guys. You guys are awesome for watching these videos if you're watching this till the end you're a true, true viewer, I guess, or whatever loyal viewer whatever you want to call it.

If you haven't already, please consider subscribing to my new youtube channel very soon. Gon na be posting some videos, I've just been banking, a lot of footage and I need to edit it down. The new channel is gon na, be called HVAC. Our tools there'll be a link in the show notes of this video.

Also, I mentioned it in my last video that we started a new discord server. It's just a way for you guys to communicate with myself and a couple other creators, some of my friends that we've kind of built this discord together and we go on there. You know maybe once or twice a day for a little while and just kind of chat with people. You can @ mention us and stuff like that.

If you have questions we're still kind of building it and learning how the whole discord thing works so feel free to check it out, there'll be a link in the show notes of this video too, and also, if you haven't already gotten your tickets, I will be At the HR conference in at the end of January, beginning of February, I will be making appearances at the sporting booth, I'm sure I'll, be possibly stopping by the field. Peace booth. I know that the event the Brian ores HVAC our school symposium. I can't remember what it's called, but it's educational training thing.

I know that they're sold out but I'll be at that too that'll be at the same time as HR. So if you guys happen to be making it to HR, send me a message or direct message. Me you know, while a HR is going on and I'll be putting stuff out on social media to saying where I'm at you know, if I'm doing like meetups or things like that, because I'll definitely be spending time at the spoiling booth. So maybe we can schedule something where people can come to the spoiling booth and meet me there whatever.

If anybody wants to meet up with me, you know, grab a bite to eat or something like that. Maybe we'll work something out so message me all. My social media is in the show notes of this video and that's pretty much it guys. Alright, I really appreciate it and we'll catch you guys on the next one.

Okay.