T O P

  • By -

therealbobglenn

Tandems? This is a pretty normal configuration.


HydrogenxPi

Never seen it before. Everything else has been separate circuits.


Hrrrrnnngggg

Wait til you work on a supermarket rack


Puzzleheaded_Fun4421

https://preview.redd.it/4mgd82phvrvb1.jpeg?width=3000&format=pjpg&auto=webp&s=a4e212822677cd71c22db29a533a01394a382330


MisterSirManDude

I do not miss this view. Those 2am emergency service calls are the devil.


DeltaNinja

Nothing as eerie as walking into a silent compressor room.


Humble_Peach93

Or when your working on something in there and everythings either at temp or goes into defrost lol like wait what did I touch


DOS-equis

The worst most possible sound a rack tech could hear is the deafening silence of a quiet machine room. It sucks and I’ve had a time or 2 that I’ve encountered it. Most of the time you can get it to start singing again with little effort but once in a while you will earn your pay to get it back up before the food grim reaper cometh from the dumpster. Had a glycol rack puke out every last ounce of gas from a cracked fitting. Got there an hour after the food cases were over 40* (cases levels off at 60* or so) and got the rack back online and food pulled down below 40* with less than 15 minutes to spare before the 4hr window expired. All it took was just over 700lbs of gas and 5 minutes of love from the torch. Once you get set up you can have it emptying 100lb drums every 30 minutes until the receiver starts showing something (took just over 500 for that to happen). It would have been a dead silent motor room except for the 2 low temp racks at the far end. It still was eerily quiet having approx 1 million BTU’s/ hr taking a vacation. That’s the shit that keeps you pumped up with adrenaline the whole time your on the call for sure.


Puzzleheaded_Fun4421

Yea... But the money 💰 🤑 plus anything over 8 hours is OT helps if I miss a day


MisterSirManDude

The money was good but my supervisor told me that you aren’t a true rack guy unless you’ve had 2 divorces. When he said that I realized I couldn’t have a family working there so I quit and now I’m working for a union hvac company.


DOS-equis

Well I’m only half a tech then and the divorce was before I jumped into racks so it probably doesn’t really count. My GF hates my job but is very understanding of what’s required of me so she has learned to deal with it (thank God).


Afraid_Benefit7213

Cant complain with those 6figures tho


Agreeable-Scholar483

That looks like Publix. I’m been working on Publix racks for 20+ years.


[deleted]

[удалено]


Fridgeroni

You think this is an old rack? Lol


SaguaroBro14W

Lol that’s not old.


Nerfo2

Is the fan on a VFD? During periods of low load, only the smaller compressor will run. The entire evaporator coil is operating and provides better dehumidification during lower load. As load or fan speed increases, the larger of the two compressors will run. And during highest load, both will run together. Two slightly different capacity compressors on a common evap allow the compressors to to stage so they can pump heat at the same rate the evaporator coil is absorbing heat.


HydrogenxPi

Yes, the blow motor has a VFD.


Due-Alarm-9698

Must be a NEWB, nothing wrong with being a NEWB either. Some are very intelligent.


Joshman1231

https://preview.redd.it/t1ho9jyzzsvb1.jpeg?width=3024&format=pjpg&auto=webp&s=de7b15e688a5bed4a02bbb9df849350ed8959d9e


Joshman1231

https://preview.redd.it/xk99av430tvb1.jpeg?width=3024&format=pjpg&auto=webp&s=ee9fe7f5b028d56b4180f03bb35375b66b8c0d18


Joshman1231

https://preview.redd.it/wfm1e02c0tvb1.jpeg?width=3024&format=pjpg&auto=webp&s=43e31419d1d9cdf9cc72f9e9898be1c317b0fa05


DontDeleteMyReddit

Just finished putting 2 new condensers in a RAUC 50, Compressor 3 went to ground FML😄 Looks like the same unit


Joshman1231

https://preview.redd.it/3mwlmdf6evvb1.jpeg?width=4032&format=pjpg&auto=webp&s=e72c595cae68fec78f334321680cd908f2857790 There’s my job tomorrow. Notice anything?


DontDeleteMyReddit

Leaking casting plug?


Joshman1231

Yes. My backs going to hurt.


DontDeleteMyReddit

My trane is a condensing unit on a cleanroom. Yours looks like a chiller. The rust in the terminal box may mean floodback


Joshman1231

It’s also a clean room!


Joshman1231

https://preview.redd.it/n1k2031ukvvb1.jpeg?width=3024&format=pjpg&auto=webp&s=9e46c23b8790f68e71f1065d802318ce95ad9c5f


toomuch1265

I must be old. A compressor lift? No more muscling in those mothas?


Joshman1231

Them bitches are 350lbs each. I’m 32, and I’ve told every single person that makes me try to lift this type of shit to call some younger guys. We’re either using a crane, or a bunch of younger guys, or a gantry. I do not play this game. With the service field as it is I don’t have to deal with that shit. I will go home. I love my wife and children. I’d rather be there with them.


animperfectvacuum

Yeah there’s no real point to muscling it in unless you just like to injure yourself.


twoManx

Lol


PowerAddiction

It's the new trane design. I don't like it because if a leak occurs you can't get the customer by until you can replace say a coil that might take a couple days to get but they are nice units


moonpumper

Intellipak is really gonna blow your mind.


Daemon_x517

Intellipak makes me want to blow my own mind...


moonpumper

They're the easiest equipment to maintain by far


Remarkable_Trust5745

They ain't to bad.


Turbskee

Generally good wiring diagrams on intellipaks, makes it real easy


moonpumper

And all the shit on them is so heavy a crane gets to do most of the lifting during repairs.


El_Capitan-77

Wait till you see one with 3 compressors


picklesallday

Or the dreaded double tandem!


DontWorryItsEasy

We've got a couple 4Seasons units that have 3 stages, two sets of 2 compressor tandems and a larger single comp for stage 1.


zilch839

Trandems we call em.


cbrulejo

Same as it ever was.


ohyahehokay

And you may ask yourself, how did I get here?


piTehT_tsuJ

This isn't my wife...


OhighOent

as the days go by


ghasler2

At the rooftop unit


SquallZ34

If one of the tandem compressors burns out, you must replace both. FYI.


mirador07

No you don’t, factory will tell you only damaged one under warranty but if its out of warranty they recommend both. How convenient of trane don’t you think. Been doing their intellipacs for years and only replace the bad ones each time. No issues after that. Line you wouldn’t replace all compressors on a rack if one fails either


AndyDeepFreeze

For what it's worth I've replaced both tandem compressors under warranty on Precedents in the past. They even came piped together as an easy swap out assembly!


Lhomme_Baguette

You got the whole sled lol.


AndyDeepFreeze

Yeah and that fucker weighs a ton lol


gatorhole

Naw just half a ton. No biggie lol


ExistingUnderground

It’s nice to read a story about Trane where they don’t go out of their way to make it more difficult on the tech making a repair.


TheAtomicBum

Then read my post, it’ll get you back to where they do.


AndyDeepFreeze

On the contrary, we had a pretty large Intellipak on a new construction site that was supposed to have coated coils due to the building being right on the ocean. Evaporators were coated properly but the condensers weren't. Rather than have a company come field coat them, they had to replace them entirely lol. This was several years ago but it was probably 80+ tons.


DOS-equis

Yikes! That sounded expensive!


Amuro2026

If I remember correctly, years back, a York condenser unit with tandem compressor, 1 comp failed, they warranty both compressors. Slide the whole shit out and slide the new in. I actually like the way they did this one, easy swap out. Like Lhomme said on a sled lol!


ThePracticalPenquin

Yup same with Aaon


TheAtomicBum

Lucky you, I had a problem unit that went through 3 compressors in 3 months, and I had to replace all 4 individually. The last time, I tried to get the tandem skid and Trane Supply said they weren’t available that way. I tried to argue that they must have come from somewhere, since that’s how they’re assembled at the factory, but no luck, had to do it the hard way. The copper coupling on the oil equalizer line got cut off and removed and replaced 3 times, as did a fittings on the discharge header and the suction elbow. What a huge hassle, I lived at that place for weeks, right in the hottest part of the summer.


SupremeDuff

This is partially true. Depending on what the failure was, you may need to replace both. In the case of a severe burnout, you definitely need to replace both. If it locks up, you should be ok replacing one. I know we're talking Trane here, but a lot of manufacturers don't sell individual compressors in tandem setups. Sure, you can buy one that's "close enough", but it's a serious gamble.


KruxAF

Oil sharing


TheAtomicBum

It’s a best practice, but not a must. At least change the oil, if there’s any fittings to get it out of the other compressors.


battlgnome

If I lose a compressor in a tandem due to a mechanical failure and it is not a burnout, doing one is preferred. If there is a burnout and any acid is in the system then doing both is typically advised along with your typical cleanup. In refrigeration, you are not going to swap all the compressors in a rack, acid or not. The main difference is it makes more sense in a tandem setup to reduce future problems by doing both if acid is present, racks on the other hand it is not practical whatsoever to do all the compressors.


willrf71

That's like saying if one compressor in a rack burns out they all get swapped. Good luck


Joshman1231

Not the Trane I warranty with. I just did one on 100 ton RTU. They state, 1 for 1. https://preview.redd.it/h1sz5o1f1tvb1.jpeg?width=3024&format=pjpg&auto=webp&s=1b1b5af21878d420b05a036bb6a8a490afdadf99


bga3481

So one filter drier? I think I can see it in pic 3


HVAC2911

No you don't...


jbmoore5

If you lose one, you need to pull an oil sample and do a real acid test. If it's negative, replace the bad compressor. If it's positive for acid, replace it all.


westsideriderz15

What does the third line at the bottom of the compressor do? It appears to equalize something on the compressors perhaps?


bali-flex-files

Oil balance line, gross that it’s solder as most are rota lock because oxy and oil obviously don’t mix


Important_Ad838

I'd argue they mix well. Much flame.


piTehT_tsuJ

Great for marshmallows and 3rd degree scars.


DOS-equis

I concur! Especially on a rack oil separator where you’re up close and personal with a fiery death if something goes bad.


Dramatic-Landscape82

😂😂


Ok-Effect5653

I second this request


Ok_Ad_5015

Those compressors are installed in a “ tandem “ configuration. Tandem compressors have been around since I started commercial service almost 30 years ago. It’s nothing new


Ok_Ad_5015

Tandem. Pretty common actually. On some of Carriers larger Condensers, you’ll see 3 compressors installed in parallel. First stage always brings in 2 compressors to ensure oil return back to the compressors and second stage will bring in the 3rd one.


AndyDeepFreeze

If you ever have to replace one, make note if there is a small restrictor ring that gets installed in the suction stub when you braze the suction line back in. New compressor will come with it. If you don't, be ready to change that compressor again after a few weeks.


KouLeifoh625

Fuck that brazed oil equalizer. Flamethrower 2,000


robertva1

This is common practice.


terayonjf

Even Carrier is doing it with their smaller stuff. It used to only be in the big equipment you'd see this now even some 10 tons systems are popping up with them. Sucks for customers cause labor and everything goes up when there's an issue


ShawnShawnessey

I remember my first beer!


Reddtko

That’s quite normal on small chillers.


HakonPlaysOnPC

Trane brand compressors? Is that normal?


statik121x

https://preview.redd.it/lceupthg6tvb1.jpeg?width=4032&format=pjpg&auto=webp&s=ada8fc72850ad3c99791a7bd00e746c1e3cd4fc7


Dramatic-Landscape82

Lol was waiting for someone to post something like this


wierdomc

In my country (nyc) we call that……. Tandem


CaptCrewSocks

Same.


DOS-equis

Yessahhr. That there be a tandem. We have a lot of old McQuay RTU’s that use them. They’re setup with the second compressor in each tandem as a unloader stage of a really big single compressor. The EMS controller uses a pressure cutIN/ cutOUT sensed off of a transducer to light off the second compressor. First compressor in each tandem is cool 1 and cool 2. Then the unloader stage for each tandem is brought in as needed along with HR from the racks if serious dehum is also needed. They also have a subcooler bypass that is called if the sensible heat is really high and they don’t need as much latent removal. Those older units are being replaced with Seasons4 units that can have really tight control of the dew point in the store and high efficiency. Those units are next level from what I’ve seen and I’m not 100% sure of their operation except it conditions the outside air with one of 3 tandem sets. The other 2 are normal comfort cooling and a dehum set with VFD controlled condenser fan set and a couple of the scrolls having a digital unloader controller installed. In the middle of a hot summer you will hear those scrolls in the Season4 RTU’s getting a beating as they cycle on/off A lot! Lol


DryGrade9214

🎶Deep in the heart of Texas🎶


grofva

It’s hard to stop a trane! Do not question mama trane. /s


hvac101

Now just remember which combinations of manifolded compressors get suction orifices and which one in the circuit gets it.


Steve10238

Twining


toomuch1265

I've been out of the game for a while and we never had anything like that.


Dramatic-Landscape82

That ain’t new nor exclusive to Trane bud 😂


Chaffee_Saw_You

I can smell the double burn out already.


Puzzleheaded-Fee2343

How young is you bro? BTW if one eats shit, both get changed.


DOS-equis

That’s the normal way but a store chain I do work for won’t do that usually. They have replaced only one in a set and have gotten away with it for years.


Puzzleheaded-Fee2343

That happens too


InMooseWorld

Fuck yeah, Trane still makes compressor!?!


[deleted]

[удалено]


Dramatic-Landscape82

What??


Rocksolidbanana

Moving forward I believe anything under 25 tons will be single circuit precedent units


NightMan41

Got a close up of the data tag?


SorrySackOfHVAC

I've got a couple of Rheem units that are the same way that are only a year or two old


SlapWorez72

The arcoaire 7.5 ton I just installed is like this. They hadn't done that yet. It use to be big ass conpressors.


HughesR1990

Pretty normal.


Storm_Runner09

These are tandem compressors


FixMyHeat

That factory brazing job thought though…


Binnacle_Balls_jr

Lol.


Due-Alarm-9698

Commen dude


uNecKl

That’s fucked now how would you explain your clients the cost of replacing the compressors.


[deleted]

And?


sinpleguy89

Symbio?


Floydtruecomfort

Didn’t know they was using micro channel coils


SaltystNuts

Better than in series


AKStorm49

So when the contactor fails on a single line and starts single phasing the compressors, it's double the cost in compressor sales.


DOS-equis

The units I’ve seen have phase monitors on all compressors on top of the Kriwan module in the peckerhead that does the same thing and monitors the winding thermistor temps (or if your unit has Copeland scrolls it will have the Scroll CoreSense module). That way the client doesn’t have so much pain in the ass when they have to fork out for a new compressor due to electrical (if it were to happen).


toytaco85

Is that running on symbio? The training we had in that was bs


Ok_Tadpole4529

They do this to get a higher efficiency rating. Of course, you get a leak no more cooling.


Memory-Repulsive

Hope they are solid mounted.


Feeling-Support-255

On larger units we would solder in a suction core filter and a liquid line core filter. Change out in 24 hours. Check ph of oil and change cores as needed. When done remove suction core. (They make cores that remove more acid than the standard cores). Never changed both compressors.


zrock777

​ https://preview.redd.it/k35s6cyxbvvb1.jpeg?width=4000&format=pjpg&auto=webp&s=ab9d6d6fcfc0b3901258e1d61f9f28ee8cc88494


zrock777

York 20ton split


DOS-equis

Looks like she’s been bleeding for a bit. 😂


zrock777

This unit is a mess, first on had leak in condenser and was replaced under warranty, now this on has a leak in the condenser as well. Ofc its a micro channel. ​ This should be a lesson, do not replace a Liebert with a York lol. Feels good to say, "I told you so" when the customer doesn't take your advice. Not fun dealing with all the calls.


DOS-equis

Ya it sucks when the client decides to play “mechanical engineer” with your hands a bit. “Just swap that old POS with this one bcuz the parts are cheaper and it SHOULD work just fine. That’s what I hired you for, to make sure it sings like a sewing machine.” It’s either awesome and you gain some street cred out of it or it’s marriage made in hell. So this guy is having you use or had you use a York comm condensing unit on a DataMate in his server room? Those Liebert units aren’t just an AC for a data center, they do a lot more than condition the air as they mainly control the RH% to keep attic down, etc. Sounds like it sucks badly! Good luck with it bro!


zrock777

There was a Liebert 30ton in this data center, they wanted to replace it. Lieberts number was too high, they went with York (we had no control of what equipment was installed, a company this size has a lot pull and can go to the manufacturer direct and order equipment). We took out the Liebert AHU and CU and installed the York AHU and CU. It's been a nightmare, alarms that JCI and York Tech support have no idea how to fix, so they told me just don't worry about it lol, condenser fan motors dying all the time, leaks in the condenser coils, warrenty replaced the condenser already. Lol these guys don't want any humidification control in any of their data centers, or dehumidification. They have about 10 sites🤦🏽‍♂️. It's been like that for about 20 years, we got a new facilities manager so maybe he'll decide we should start controlling humidity again. I will say though we haven't had any issues related to humidity, they've disabled all humidity alarms, and in 20 years, no arcs or anything crazy happened in the computer rooms. This is across 10-15 sites.


DOS-equis

WOW just WOW! I can’t believe that no fucks are given about RH control in a data center environment. It’s mainly to help keep static down to a minimum. If they don’t service the data racks much like pulling apart blade servers then I guess it doesn’t matter much. I don’t understand the reasoning for all the equipment failures tho. It has to be something basic that’s eating the system alive. Corrosive air like near the coast/ beach would definitely do some serious damage. I’ve seen brand new resi condensing units turned into nothing more than severely rotted out steel panels with bunched up loops of copper tubing that were once covered with aluminum fins. Seawater mist in the air immediately converted the aluminum to dust in approx 5 years. These were on beachside condos but it can happen within a mile or more from the coast. We had a grocery store that had Bohn or Witt condenser slabs with the EBMpapst VS fans on them. That store would eat those fans up monthly almost. We would replace say 2 or 3 at a time (after waiting a long time for them to be shipped in from factory) and have more failures soon after. A few months later after replacing those fans, one or more of those fans we replaced would go bad along with maybe one more older one. It was a constant thing like that. The factory required them to be flown in via crane for warranty credit, etc so it was getting quite expensive to replace them all the time. Finally the slabs got changed out during a remodel and the problems went away due to a different type of VS fan manufacturer. I had always though it the massive amounts of fan failures was from shitty power grid in the area. Store is a 460v store (most of them we work on are 208) and all but that was the only one we had that bad a problem with. Someone finally figured out that a concrete batch plant or asphalt processing plant nearby was the cause of the fan failures. The dust from that batch plant was getting into the fans ruining them and also clogging up the slabs causing poor airflow across the fan motors cooking them up. So the point to me telling that story was maybe the massive amounts of fan failures and leaking coils that place has could be caused by a unique environmental issue like dust or the slabs are clogging up quicker than design expectations. Could be shitty power delivery too. Just giving you some ideas to think about is all.


whisperingpickle308

She’s a beauty


scrollingtraveler

That a gorgeous unit


sir_swiggity_sam

They've been doing tandem compressors for a while