Today we have a package unit, that's not working properly. This is a Linux. I believe it's an 18-ton we'll confirm that in a minute. First thing we do, is we open it up and a circuit bar? We have an error code.

10 error. Code. 10. Right here is 24-volt power loss terminal 835.

So whenever I see anything 24 volts, the first thing I want to do is look at transformers. Okay, this unit has dual transformers with a resettable circuit, breaker, no one's tripped. So we have the trip circuit breaker on the transformer okay, before we do anything, we're gon na go ahead and check to see if anything is, grounded or shorted on the low-voltage side of that transformer, by putting our meter on continuity, turning off power to the air, Conditioner and testing from each leg to ground to see if we have anything that's shorted out before we just try to reset it and or replace the transformer. So I'm gon na get my meter out and we'll start checking things.

Okay, so I turn main power off for a minute just to check to make sure there was no electrical problems that I could see. So I can jiggle some wires around stuff nothing jumped out at me. I turned main power back on we're gon na test three-phase power coming into this guy. We got 3-phase coming into the unit.

I already reset the transformer, but I pulled the to low voltage wires off of the terminal board. That's in the back there, so the low voltage wires are safely secured. You know just kind of tucked up in here, so I can test to see if we've got 24 volts, so the transformer is outputting 24 volts, whether or not there's still a problem with the transformer. We don't know it could trip under a load who knows, but that tells us that right now the Transformers you know best as we can tell is working ok.

So now what I need to figure out is this is transformer T 18. I need to figure out what that controls and I'm going to investigate those components before i hook power up and go any further, maybe I could find a problem with the components that that transformer can controls. So what we will do is I'm going to find I'm going to look at the schematics right here, I'm going to find that transformer on the schematic and see what things that transformer controls and then I'm going to test those components. Okay, so what I found someone over here to my schematic - and I noticed that there's a transformer here and there's a transformer here - my transformers labeled T 18 and the other transformers labeled t1 - so t1 is right here.

T 18 is my transformer there's the circuit breaker on my transformer and here's my line going to my ladder diagram. So what I ended up doing was. I followed my ladder diagram and I circled every point that one that one that one that one that one and that one that my transformer went to a relay or a load, I should say so. Those are all the items that I'm going to the investigating before.

I start resetting that transformer. I like Linux, because they label everything. K1. 49K.

150 k. 14K. 146. K3.

Those are where I'm going to start and then you could follow them across to the other things they go through. So it looks like it goes through pressure controls. Another thing that I notice is up here in the unit that transformer t18 says it goes to the contactors, and this one says it goes to control so and that does kind of make sense, because my loads right here k, 149 k 150. Those are relay coils.

I believe, and then I see pressure controls here, so that makes a lot of sense, so I'm gon na start looking into those items again. This is all before I reset or rehook up that transformer, as I'm going through everything here, like I showed you, I'm just gon na start at the back of my ladder diagram here, we're gon na start at actually we'll start right up here at the front K 149, k 149 is labeled right up in here k: 149. It's the relay for outdoor fan number three. I went ahead and pulled the relay out.

It's an IceCube relay just to investigate it and then we're gon na go through each component. Like I said, they're labeled and we're gon na test the low voltage coils to make sure everything's working properly on them. So at this point, I've gone through and tested all the relays check the resistance values, compare them to each other, made sure that nothing was grounded out. I marked all the relays.

I checked this one, this one, this one, those two up there and now I'm not seeing any problems yet so, in my opinion, I've done everything that I can. I've traced the wires all the way back to this board, don't see any problems. I've investigated everything that I could so at this point. I've got to turn on power and just see what happens, but the important thing is that I took the time to verify that there was nothing obvious that jumped out at me.

This is when you got to have your eyes and ears open right now, because you may only get one chance at this. You may hear you may see. What's going on, you just got to pay attention. I'm gon na turn power on right.

Now we didn't trip right away, so we just want to listen that another error message, number 52 up and we just tripped so whatever is happening - is happening right away. It's interesting that we got another error code 52 limits which open secondary heat limit is open. That's interesting, you know you wouldn't think that anything to do with the gas system would affect us right now, but it's always possible, so we're gon na go ahead and turn that off and go inspect the limit switches to see if we see any shorted out wires On the limit switches, one of the really cool things I like about these older Lennox units is the blower assemblies pull out really easy, so you can access the bearings to grease them and here's all our limit switches right here secondary there's a broken wire. These limit switches, don't look too hot, so I'm gon na fix this wire and then we're going to test it.

I believe that's a ground wire but we'll see and then we'll test everything and see if there's anything else, that's causing a problem. Okay, so I think I found it when I found that wire. That was, that ground wire that pulled off on that limits, which it had rubbed against another wire. It rubbed against this white wire inside there or one of the white wires, and I was getting continuity on this wire before I pulled that blower assembly out once I repaired that ground wire and risa cured it, I'm not getting continuity anymore on that wire now wires.

Going to the coil, but I'm still getting test it yeah, so see no continuity anymore and I was getting continuity. I believe that that ground wire was rubbing up against something it shouldn't be, and it was causing this unit to trip. Now it's important just a minute ago, I said we're gon na listen, we're gon na watch, we're gon na use our eyes and our ears because it tripped. But then I saw another error code error code.

52. Now I really had no, which way to start on this unit. I'd have been tearing apart every single wire to try to find a short, but that error code popped up and it kind of got me thinking and that's what made me look at the limit switch and then I said hey. Maybe I should start there, even though that error code is still on here.

There was obviously something going on with the limit switch, so I started there and I believe I found the short now. I also moved a bunch of wires around, so I'm gon na watch. This unit for a little while to make sure that my short wasn't somewhere else and maybe by moving the wires I just fixed. The short you know like the wires, aren't touching ground anymore.

So that's why I'm gon na watch this unit jiggle a bunch of wires, but at this point I can start this unit up and it stays running and the compressors all come on to so and it's not tripping anymore, so we're gon na watch this unit for A little while, while I'm watching this unit turn on what bugs me is that I see an enthalpy sensor sitting right here and I'm wondering why the heck is there an enthalpy sensor here. So then, again, I'm just watching the unit operate, and I come over here and the enthalpy sensors missing from the economizer damper in here. It should be mounted right in here. This should be plugged in right to that blood.

So that's definitely a problem. Then I got in here to look at this economizer. You guys hear that sound the gears inside the motor of that economizers, not working right. I haven't checked voltage yet, but my economizers fully open and it's not moving and then I went over to the economizer control on the circuit board and turned it, and this thing doesn't open at all.

You can just hear the gears grinding inside there. So they've got a bad economizer motor too. So just because I want to look at the big picture, I put my gauges on all the circuits check out all the pressures and I'm kind of blown away. This units 2003 model - I've serviced it since 2004.

I think - and it really has not much been done - we changed the circuit board on it a couple years back. Refrigeration was it's never been cut in two, it's got perfect charge. I mean, shows you man. I really liked these LGA units, the new units that they're making they're nice, but I don't know man there's something about these - that I really really like the the new ones that have the prodigy board.

I mean the prodigy board. Has its pluses there's things I like about it, but I'm just so used to this: was it an m18 board yeah? I think so. I think it started with m16 and went all the way up to the m18. I think that's what it is, but um yeah.

I really liked this board. It was really easy to work with, but anyways I mean not knocking the prodigy board. The Prodigy ones are nice too they're just a whole new beast to get used to cool thing about the prodigy. Is it's a lot easier to hook? Your computer up to this one, you could do it, but I just find it easier with the prodigy to be able to set parameters and different things, so refrigeration, wise, we're looking good.

All the condenser fan motors are running pressures. Look good, we're gon na order. Some limit switches, you know just like if you've seen any of my other videos when I order limit switches, I order all the limit switches, so there's three limit switches for the gas heat on this guy, I'm going to change them all. At the same time, we're also going to order an economizer motor and we're also going to order an enthalpy sensor for the outdoor air damper, because we can't open the outside air damper at all right now to get any fresh air in the building.

This restaurant doesn't really use the economizer, for you know the economizing function they more or less just use it for minimum outside air. So it's been balanced that way, they don't like the variable outside air damper, opening and closing. So we just need a minimum amount of outside air on this unit. So that's why we got to get that outdoor air damper back on and get the enthalpy sensor back on there.

So that way we can modulate those dampers and get them there fresh air to help balance out the building. I'm finding that as a trend in these restaurants. I don't know if you guys noticed this. Let me know in the comments that we are not putting makeup air units on the roof very much anymore.

For the most part, sometimes you find them, but they're, usually really small, if you do most of the time we're pulling our outside air through the ACS. I understand it's the meet code because they have minimum fresh air coats that they want, basically to vary depending on the amount of people in the building. So a lot of times, they'll use the ACS when they stage up assuming there's more people in the building. I mean there's lots of logic to it.

There's really no great way to perfectly figure out adjusting the outside air dampers. Some people try to use co2 sensors. There's faults in that too, because a lot of times the co2 sensors are located in the wrong spots and they prematurely open and bring a lot of outside air in the building. I tend to find.

I don't know if you guys see this, but I tend to find buildings that use demand, control, ventilation using co2 sensors to have a lot of nuisance, complaints in the wintertime about cold air in the building and, typically what I notice is that the restaurants, it's hard To convince them to keep their blower motors running so they tend to put the blowers into auto, which in a restaurant that doesn't work, but they tend to put the blowers into auto. So when they finally get a call for heat it, they get a blast of cold air in the building. I prefer to leave them in the on mode, so that way, you're getting a steady amount of fresh air in the building. So that way the heat can properly regulate and you don't get those high and low temps, but anyways have you guys been seeing that I've been noticing the trend since we've been using demand, control, ventilation of more complaints, and they just never seem to work correctly.

I tend to find the customers are a lot happier when they just have minimum outside air and not a modulating economizer. I think that there's a place for a modulating economizer. I understand the efficiency potential and the energy savings, but I think that we don't have the technology to perfect demand control ventilation. Quite yet, or at least it's not mainstream or cheap enough.

So I think that you know for now we just kind of struggle. I really think that wish. I should say that more customers would like to use economizers most of the time. Restaurants, don't want to fix them, they don't want economizers fixed because to them they just don't understand the savings or they the savings doesn't realized.

You know restaurants tend to not be too focused on electricity bills, at least in my case. They tend to be. No, you know. Basically, they just want their equipment working and they look at the numbers of sales that they sell food.

I don't know if it's a true fact that they don't save as much with the economizers. I kind of wonder if it's more hype than it is actual savings. Anyways, I'm going off on a tangent, we're gon na order. The parts for this unit alright.

So electrical short on the a/c found it to be a low voltage wire problem, one of the heater safety limit switches, a ground wire broke off and rubbed up against the power wire shorted, the transformer out. While I was doing that, I found that the limit switches are actually bad, also found that the economizer motor and the enthalpy sensor about went ahead and put my gauges on the unit went through all stages. Everything refrigerant charge was looking pitching air flow looked decent. Everything else checked out about the unit, so it was just a basic electrical short we're gon na go ahead and order some parts and head on back out there and get those replaced, but for now they're good to go.

Watch the unit for about half hour. 45 minutes operate. Everything was good, alright catch you on the next one.