1 00:00:00,000 --> 00:00:07,000 Tales from the Trenches, stories forged in the fires of experience. 2 00:00:07,000 --> 00:00:15,000 Alright, thank you everyone. We are joining Patrick Murphy in a follow-up conversation from one of our Teaching the Unteachable sessions. 3 00:00:15,000 --> 00:00:22,000 This one with Tales from the Trenches is going to be about deep searching for refrigerant leaks. 4 00:00:22,000 --> 00:00:24,000 Welcome. Glad to have you here, Patrick. 5 00:00:24,000 --> 00:00:26,000 Yes, glad to be here. 6 00:00:26,000 --> 00:00:30,000 Alright, let's dive a little deeper into this one because I love this store and this is a great one to pass on. 7 00:00:30,000 --> 00:00:32,000 A lot of good educational opportunities. 8 00:00:32,000 --> 00:00:41,000 You know, leak detection methods have improved so much over the years, but they still require some time to go through a system and totally check it. 9 00:00:41,000 --> 00:00:42,000 Yeah. 10 00:00:42,000 --> 00:00:49,000 Now, if you have a brand new system that you've just installed and you've got a leak, you're going to be tearing your hair out. 11 00:00:49,000 --> 00:00:56,000 And I will literally tell you that's exactly the circumstance we ran into. 12 00:00:56,000 --> 00:01:02,000 We had a brand new system that was installed in a supermarket. It ran three meat cases. 13 00:01:02,000 --> 00:01:06,000 The machine room was downstairs in a basement and we charged the whole system up. 14 00:01:06,000 --> 00:01:10,000 The system was running fine for two or three days and then it started to leak. 15 00:01:10,000 --> 00:01:18,000 Now, you naturally start to check everything. We're in the cases, we're in the machine room, we've gone over everything. 16 00:01:18,000 --> 00:01:25,000 We're shutting things down and building pressure up to 400 PSI because that's what these evaporators would handle. 17 00:01:25,000 --> 00:01:28,000 And we cannot find the leak. 18 00:01:28,000 --> 00:01:33,000 And what you have to do is you have to start to think, okay, where are the possibilities of the leaks? 19 00:01:33,000 --> 00:01:37,000 Right. Map it out a little bit. Visually map out the entire installation. 20 00:01:37,000 --> 00:01:42,000 Those overall possibilities, well, where else could there be a leak? 21 00:01:42,000 --> 00:01:49,000 Well, to get to supermarket cases in a machine room that many years ago, you ran pipe in a trench. 22 00:01:49,000 --> 00:01:54,000 That's exactly right. People don't realize how many trenches are in the floors of grocery stores. 23 00:01:54,000 --> 00:02:01,000 And the trench was then covered over with a wooden floor because at that time they put wooden floors in meat rooms. 24 00:02:01,000 --> 00:02:06,000 In this particular instance, we could not find a leak in the cases or in the machine room. 25 00:02:06,000 --> 00:02:15,000 And one of the guys said, I'm going to find this leak. And he attached his leak detector to a 50 foot length of quarter inch copper tubing. 26 00:02:15,000 --> 00:02:18,000 Oh, there's an interesting idea. To be able to get down into the floor? 27 00:02:18,000 --> 00:02:24,000 No, actually, the trench to the meat room was right off the machine room. 28 00:02:24,000 --> 00:02:25,000 Okay. 29 00:02:25,000 --> 00:02:32,000 And literally, we ran that tubing in and at about 25 to 30 feet in, we picked up a leak. 30 00:02:32,000 --> 00:02:33,000 Oh, be darn. 31 00:02:33,000 --> 00:02:37,000 So, yeah, up we go. The carpenters are still on the job site. 32 00:02:37,000 --> 00:02:42,000 We make them tear the floor up. The sleepers for the floor are 16 inches apart. 33 00:02:42,000 --> 00:02:52,000 And wasn't it funny that the nail that was shot into the suction from a healthy gun was dead center between the two of them? 34 00:02:52,000 --> 00:02:53,000 Wow. 35 00:02:53,000 --> 00:02:58,000 It was just one of those leaks that it was almost impossible to find. 36 00:02:58,000 --> 00:03:02,000 Sure, absolutely. And where you had to get a little creative in how you utilize your tool. 37 00:03:02,000 --> 00:03:06,000 I mean, our leak detector is a tool. We know that there's a leak somewhere further than the tool can reach. 38 00:03:06,000 --> 00:03:08,000 How do we extend the reach of our tool? 39 00:03:08,000 --> 00:03:18,000 Exactly. Exactly. And, you know, those are not the only times that a technician in the field is going to have to use his imagination to try to find the leak. 40 00:03:18,000 --> 00:03:19,000 Oh, yeah, absolutely not. 41 00:03:19,000 --> 00:03:24,000 Or to find out anything that's going wrong on the system. 42 00:03:24,000 --> 00:03:33,000 I mean, we've literally had circumstances where high head pressure, same hundred ton air conditioning system is cutting out every other day. 43 00:03:33,000 --> 00:03:36,000 OK. So commercial split system. 44 00:03:36,000 --> 00:03:38,000 No, it's a big commercial split system. 45 00:03:38,000 --> 00:03:39,000 Yeah, OK. 46 00:03:39,000 --> 00:03:41,000 And it's in a big box store. 47 00:03:41,000 --> 00:03:42,000 Yep. 48 00:03:42,000 --> 00:03:46,000 And you're checking the high pressure control. You're checking this. You're checking that. 49 00:03:46,000 --> 00:03:52,000 You've thought of everything. And the big box store manager is not happy that you've been back three or four times. 50 00:03:52,000 --> 00:03:54,000 Sure. Whatever is not right. 51 00:03:54,000 --> 00:04:01,000 And you clean the condensers at the beginning of the cooling season only because they haven't been cleaned in four or five years. 52 00:04:01,000 --> 00:04:04,000 What? We never run into that, do we? 53 00:04:04,000 --> 00:04:13,000 Yep. And you walk up on the roof and you're looking at the condensers and you can literally stand inside these condensers. 54 00:04:13,000 --> 00:04:14,000 Yeah, absolutely. 55 00:04:14,000 --> 00:04:19,000 But you're looking at them from the outside and they look clean. 56 00:04:19,000 --> 00:04:22,000 There's nothing to matter with them. 57 00:04:22,000 --> 00:04:27,000 And you turn around and behind you, there's an earth moving device. 58 00:04:27,000 --> 00:04:28,000 Clearing some land. 59 00:04:28,000 --> 00:04:32,000 And dust is wasting across the top of the unit. 60 00:04:32,000 --> 00:04:33,000 Yeah. 61 00:04:33,000 --> 00:04:38,000 And they're converting an old drive in movie theater into a housing development. 62 00:04:38,000 --> 00:04:40,000 OK. Now I'm following along. 63 00:04:40,000 --> 00:04:44,000 And the dust has just finally coated the condensers. 64 00:04:44,000 --> 00:04:45,000 Real, real fine dust. 65 00:04:45,000 --> 00:04:46,000 Super fine dust. 66 00:04:46,000 --> 00:04:49,000 OK, now I'm starting to paint the picture. I can, you know, I can see this condenser, right? 67 00:04:49,000 --> 00:04:51,000 You're doing a good job explaining this one. 68 00:04:51,000 --> 00:04:54,000 Yeah. Those condensers wound up being cleaned three times that summer. 69 00:04:54,000 --> 00:04:55,000 I gotcha. 70 00:04:55,000 --> 00:05:00,000 Which was there was nothing we could do about it, but they had to be cleaned. 71 00:05:00,000 --> 00:05:05,000 And, you know, we would tell that to the store manager and he would go, you just keep. 72 00:05:05,000 --> 00:05:06,000 You just cleaned it. 73 00:05:06,000 --> 00:05:11,000 My system is clean, he said, because I don't want to lose any more chocolate. 74 00:05:11,000 --> 00:05:18,000 Because every time the condensers would go down, the building would get too warm and start melting chocolate. 75 00:05:18,000 --> 00:05:19,000 The chocolate would start to melt. 76 00:05:19,000 --> 00:05:22,000 So it was more important to keep the systems in operation. 77 00:05:22,000 --> 00:05:27,000 Right. So you know, you know, this is going to be called the chocolate story for now on. 78 00:05:27,000 --> 00:05:29,000 You can call it chocolate story. 79 00:05:29,000 --> 00:05:32,000 I love it. It's so true. 80 00:05:32,000 --> 00:05:34,000 I mean, we think about that may not have been covered in large amounts of dirt, 81 00:05:34,000 --> 00:05:38,000 but just that fine dust is enough to pack inside of the condenser coil. 82 00:05:38,000 --> 00:05:39,000 Yes. Yes. 83 00:05:39,000 --> 00:05:45,000 I mean, and again, you have to use all of your senses when you're out there in the field. 84 00:05:45,000 --> 00:05:50,000 And actually when you're in the classroom to know exactly what's going on when you're doing all the different things. 85 00:05:50,000 --> 00:05:57,000 Plus trying to manage the fact that you've got, you know, 10 to 15 people in the classroom who are working with somewhat dangerous equipment at times. 86 00:05:57,000 --> 00:05:59,000 Oh, yeah, absolutely. 87 00:05:59,000 --> 00:06:08,000 So that's, you know, it's just all of these little things add up when you're driving to whatever job site you're going to start to think ahead of time. 88 00:06:08,000 --> 00:06:12,000 Okay. What's been going on with this new piece of equipment or old piece of equipment? 89 00:06:12,000 --> 00:06:22,000 I mean, if you had a rainstorm go through and the design of the supermarket was such that they they put the transformer in a low spot 90 00:06:22,000 --> 00:06:27,000 and the drain for the entire parking lot was in that low spot. 91 00:06:27,000 --> 00:06:30,000 And it was one of those torrential summer rains that you get. 92 00:06:30,000 --> 00:06:34,000 And next thing you know, the transformer is covered in mortar and shorts out. 93 00:06:34,000 --> 00:06:37,000 Oh, wow. Okay. And I've seen a lot of transformer pits before. 94 00:06:37,000 --> 00:06:40,000 So, you know, a very common installation. Yes. 95 00:06:40,000 --> 00:06:49,000 And you wind up with an instance where you have to keep that frozen food for making sure there's a lot of product in there. 96 00:06:49,000 --> 00:06:52,000 Yeah, absolutely. What do you do? 97 00:06:52,000 --> 00:07:01,000 Hopefully you have a dry ice place near you and you can make sure you put somebody in a vehicle loaded with dry ice who's smart enough to leave the windows open. 98 00:07:01,000 --> 00:07:06,000 Sure. And hope that the police don't stop them because the vehicle will be sublimating 99 00:07:06,000 --> 00:07:12,000 as you drive. I can only imagine sitting here thinking about what that would actually look like. 100 00:07:12,000 --> 00:07:21,000 Yeah. Well, I can tell you I can tell you exactly what it looks like, especially pull up and you're you're wearing a ski hat ski jacket in the middle summer. 101 00:07:21,000 --> 00:07:28,000 And hair is hanging out of the back of your head because you're about 19 years old and it looks at you and goes, where are you going? 102 00:07:28,000 --> 00:07:31,000 Hold on a minute. You better explain yourself, son. 103 00:07:31,000 --> 00:07:37,000 You had to explain myself that all this dry ice is going in the freezers and it sure saved the day. 104 00:07:37,000 --> 00:07:45,000 We were able to save that. That's that is so interesting because a lot of people don't realize, especially, you know, for our younger techs out here that are getting into commercial refrigeration. 105 00:07:45,000 --> 00:07:52,000 This is an eye opener. I tell this to all my friends when we start talking about refrigeration at grocery stores. 106 00:07:52,000 --> 00:07:59,000 We've not sized a generator to run the refrigeration systems in quite a few decades. 107 00:07:59,000 --> 00:08:05,000 You know, the capacity of a generator that would be needed to run the entire mechanical system is quite mind boggling. 108 00:08:05,000 --> 00:08:11,000 So all of our emergency generators at our grocery stores, those are for lighting and emergency operations. 109 00:08:11,000 --> 00:08:19,000 They're not for refrigeration. So when we lose electrical, yeah, now we go into panic and emergency mode. 110 00:08:19,000 --> 00:08:26,000 You talk of another circumstance in a supermarket where we just finished a repair on the air conditioning in the supermarket. 111 00:08:26,000 --> 00:08:32,000 Yep. As we walked out the front door, I mean, we just replaced, you know, a hundred ton motor. 112 00:08:32,000 --> 00:08:36,000 You walk out the front door and you hear an explosion. 113 00:08:36,000 --> 00:08:42,000 And you're like, no, this can't be. You go racing back in. You're in the machine room and you don't smell anything. 114 00:08:42,000 --> 00:08:50,000 And you're looking around. You start testing things with your working with a flashlight on your shoulder and you're sure whatever you can find. 115 00:08:50,000 --> 00:09:01,000 And you look at the store manager, you say, you know, I can't figure it out. And you walk out the back door and you see a fuse on a telephone pole has blown. 116 00:09:01,000 --> 00:09:08,000 Oh, wow. You call the electric company. They come in and they say, oh, yeah, we've got to check the transformer. 117 00:09:08,000 --> 00:09:17,000 Hopefully it's not bad. And they open the transformer up and you're standing there and you look down and you know, oh, that rat must have been in there for a long time. 118 00:09:17,000 --> 00:09:23,000 Look how dried out he is. The guy from the electric company looks at you says, no, that's your problem. 119 00:09:23,000 --> 00:09:29,000 He was jumping between L1 and L2. The tail was on L1. Oh, my God. 120 00:09:29,000 --> 00:09:37,000 He was on L2 and that's the 10,000 volt before transfers down to 480. Oh, my goodness. 121 00:09:37,000 --> 00:09:44,000 So you had a nice freeze dried rat. Right. On the primary side of the transformer. On the primary side of the transformer. 122 00:09:44,000 --> 00:09:58,000 And those are the kinds of things you've got to look all over the place. You can find everything to make sure that you you don't have an instance where, you know, something outside of your control has taken over and gotten to the system. 123 00:09:58,000 --> 00:10:02,000 Yeah, absolutely. Yes. Very, very good. I love that story. 124 00:10:02,000 --> 00:10:06,000 I mean, because it's so true of the scenarios that you will encounter while out in the field. 125 00:10:06,000 --> 00:10:20,000 And it's about getting that mental preparation, painting that picture before we get there. That's the reason we're doing these in podcast form is to paint that picture of what things you have to encounter when you're on the job site or before you even get to that job site. 126 00:10:20,000 --> 00:10:29,000 Yes. On the way to the job site, you just start to think of, OK, why am I going to it? Is it a service call where there could be an issue? 127 00:10:29,000 --> 00:10:42,000 Customer is saying, I don't have any air conditioning. You have a multitude of things that could cause that. Yeah. Classic one is the air conditioning unit is put in a spot where it's it's close to a hedge. 128 00:10:42,000 --> 00:10:49,000 And you get to the job site and you start the unit up and you can hear the unit run, but the condenser fans not running. Sure. Right. 129 00:10:49,000 --> 00:11:03,000 You open the unit up and the condenser fan motor is very hot. But you look at the shaft at a condenser fan motor and it's got this lovely roping around the shaft. 130 00:11:03,000 --> 00:11:16,000 And you're like, what is this? And you trace it back and you find out it's a vine that grew into the condenser. Sure. Got inside the condenser area, wrapped itself around the shaft. 131 00:11:16,000 --> 00:11:23,000 Yeah. The shaft spun around and seized the motor. Once you cut everything loose and the motor cooled down, everything was fine. 132 00:11:23,000 --> 00:11:31,000 Which brings up another point to think about. You know, how often in the field do we have to expedite that cooling process of a condenser fan motor? 133 00:11:31,000 --> 00:11:39,000 You know, one of the tricks of the trade is to go grab a garden hose and help cool down a condenser fan motor or a compressor that is overheated. 134 00:11:39,000 --> 00:11:47,000 Yeah. There's so many opportunities that we have while we're assessing our scenario to help expedite things to get things back up and running again. 135 00:11:47,000 --> 00:11:55,000 You talk about keeping things running. We're all talking about the cold weather heat pumps today. Sure. Hot topic. 136 00:11:55,000 --> 00:12:04,000 The first heat pump I worked on was 150 tons. Oh, wow. It was very advanced. It was in a manufacturing plant. 137 00:12:04,000 --> 00:12:17,000 It would generate cold water and hot water at the same time. And it fed three 20,000 gallon storage tanks. Oh, really? 138 00:12:17,000 --> 00:12:29,000 And it had a storage system and it was really sophisticated for its time. Yeah. We're going back to the 60s. No kidding. Yes. 139 00:12:29,000 --> 00:12:43,000 And the issue that came up was on a real hot day. Once the storage was at full capacity on the tanks on the water tanks and you couldn't store any more hot water in there. Right. 140 00:12:43,000 --> 00:12:53,000 You had to get rid of the heat somewhere. OK, sure. Unfortunately, when they designed the system, it was 150 ton heat pump, but they only put 100 ton condenser in. Oh, OK. 141 00:12:53,000 --> 00:13:10,000 And when you say grab a garden hose, the eventual solution on a hot summer day was we wrapped a green flat garden hose around the top of the condenser, the air cooled condenser, and made it an evap condenser. 142 00:13:10,000 --> 00:13:24,000 We literally little municipal water supply and sprinkler. We literally tied it on to a reverse acting head pressure switch. Yep. And when the pressure got high enough, we turned on the garden on the water. 143 00:13:24,000 --> 00:13:41,000 I love it. Yes. Is it what you really want to do in today's market? No, absolutely not. You will. You will hopefully have an engineering circumstance that has not put 100 tons with 150 tons. But yeah, exactly. At that time, that was that was a temporary solution. 144 00:13:41,000 --> 00:13:51,000 According to the engineering standards they had come up with at that time. Sure. Absolutely. Because they were anticipating some of that load shedding being on the water supply at all time. Definitely. Yeah, absolutely. 145 00:13:51,000 --> 00:14:09,000 So a lot of times it's a matter of evaluating our equipment and looking for some of the circumstances. I used to encounter the same thing quite a bit in remodels, especially grocery store remodels, where an engineer would change the capacity of the cases and anticipate that a condenser having a certain capacity to it. 146 00:14:09,000 --> 00:14:16,000 But may have had some modifications over time. And then you end up with systems that don't have proper condensing capacity for your amount of cases. 147 00:14:16,000 --> 00:14:28,000 And a lot of times I won't show up until the middle of summer or the middle of winter. So a lot of times when we have to go reevaluate our total capacity on our indoor equipment versus our outdoor equipment. 148 00:14:28,000 --> 00:14:36,000 Yes, you have to look at the equipment and make sure that it's going to match up. You also have to be inventive during remodels. 149 00:14:36,000 --> 00:14:49,000 Because during remodels, sometimes you're moving a set of cases down six foot to add the new case in or eight foot to the new case. Now with today's cases, I don't believe you'll be moving them as much because there's so much glass doors. 150 00:14:49,000 --> 00:14:57,000 Right. But literally we've had cases that had to be moved eight foot down to put a new case in and you had to keep all the product in it. 151 00:14:57,000 --> 00:15:08,000 Sure. And so we put a hydraulic jack against it and jacked it down. But before we did that, we ran the tubing and then the tubing just flattened out as we jacked it down nice and slow. 152 00:15:08,000 --> 00:15:15,000 Oh, okay. So you have to be creative. Our jobs are not just, you know, this is the way we do it. 153 00:15:15,000 --> 00:15:22,000 You have to think outside the box on a lot of circumstances for all the different occasions you can run into. 154 00:15:22,000 --> 00:15:27,000 Yeah, absolutely. Patrick Murphy, thank you once again for joining the show. We're grateful to have you here with us. 155 00:15:27,000 --> 00:15:56,000 Great. Thank you.