Liebert MiniMate Plus

[storyusmc]

Hey guys I am having a problem getting gauges on this unit. This unit is in the celling and I can't get to it. The unit keeps shutting off. I have to keep hitting the compressor reset. The unit will cycle on a few time but then I will have to hit the reset again. I have a temp of 82deg entering the Condensor and has a 140Deg Leaving. The Entering pressure is 130psi and Leaveing at 100psi.
Need you thoughts on what it could be. The unit was running fine. We cleaned strainer and the filters are good.

Thanks,



A newbie

[The Saint]

Was it the High Pressure Reset switch that you keep on resetting?

[storyusmc]

Yes it is

[The Saint]

Originally posted by storyusmc
Yes it is

Check the ff:
Blockage in the condenser section
Fan motor (it should be running)
Suction pressure and temperature
Discharge pressure and temperature
Suction and discharge pressure switches settings

What's the the refrigerant?

[storyusmc]

I can't get Suction and Discharge pressure or temp atm. I am working alone and the unit is in the ceiling. The compressor though is running hotter than normal. Way hotter. I even burned my hand on it. I know that it usually run about 140Deg but this feels much hotter that 140. If it's necessary, I will wait until tomorrow when someone is around to get the suction and Discharge for you. Right now I am just looking for a general assumption of it could be blown motor bad compressor cause that’s what I think it is but before I replace it and do those steps just wondering if that what it could be or did I miss something.

[storyusmc]

I found a cleaner who will make sure I don't fall off the latter. I will get the suctions and dischage temps and pressure.

[The Saint]

ok. Do the first 2 steps I mentioned above

[storyusmc]

Ok I have 63 Suction and a 235 Discharge pressure. Suction temp was 36deg and the Discharge temp was 105. Tomorrow when I have someone here, I would like to put the gauges on and leave them for about 1hr. Cause that’s when it seems to be shutting off. The only info I got on the until was, the design test pressure of High 300psi and Low 150psi.

[The Saint]

You should verify if the condenser fan motor is running and if the condenser is clean.

[storyusmc]

The Fan is running and the Condensor is clean.

[The Saint]

Check if the discharge service valve is backseated (open for discharge pressure to come out)

Another thing. Your superheat should be 10 to 20 degrees.

[Edited by The Saint on 09-12-2006 at 04:52 AM]

[storyusmc]

There isn't a 3way valve. Just has Schrader valves. The superheat is fine. It cools the room down crazy fast but after about 1hr thats when I have to start hitting the reset. What is causing to do this?0.

[The Saint]

Try to remove some of the refrigerant. You might be overcharging the system. Your superheat is 0 degrees.

[storyusmc]

Didn't mean to put the 0 in it. The superheat had a +12 deg difference.

[storyusmc]

I am beginning to think that it might be an Overload problem. Where to start op checking that?

[The Saint]

Originally posted by storyusmc
I am beginning to think that it might be an Overload problem. Where to start op checking that?


Do you have a Instant Messenger hotmail id? maybe we can troubleshoot it faster thru that link.

[storyusmc]

Well I still have some more op checking to do first. I want to check the water reg valve and make sure it opening and closeing. I want to start the unit and leave the gauges on and see what the unit is doing. Then I will chech the 24V lines that I know about. I will have my partner in tomorrow so that will be a help. I just hope it the water regulating valve on the unit. I think it's just a little strange that the supply psi and return psi has a 30psi difference. The only thing I will need help with if you are around tomorrow is trying to figure out how to see if there is a short in the motor The Compressor is Hermeticaly sealed. Thanks for you help. If you are on tomorrow night ill give you my yahoo IM then. Thanks again.

[The Saint]

Originally posted by storyusmc
Well I still have some more op checking to do first. I want to check the water reg valve and make sure it opening and closeing. I want to start the unit and leave the gauges on and see what the unit is doing. Then I will chech the 24V lines that I know about. I will have my partner in tomorrow so that will be a help. I just hope it the water regulating valve on the unit. I think it's just a little strange that the supply psi and return psi has a 30psi difference. The only thing I will need help with if you are around tomorrow is trying to figure out how to see if there is a short in the motor The Compressor is Hermeticaly sealed. Thanks for you help. If you are on tomorrow night ill give you my yahoo IM then. Thanks again.

No problem Bro.

[madhat]

Get the model and serial numbers of the unit. Call Liebert and ask them if your unit has one of the Driers with the dacron strainers in it. Also they had units out, that the motors would run backwards some of the time. There are service bulletins on both these problems, from Liebert.

[Edited by madhat on 09-12-2006 at 12:38 PM]

[atmosphere]

My stars, man, you've gone from a condensor fan motor and coil that is clean to a water cooled unit with a regulating valve!!
I sure hope you aren't hustling anyone into thinking you know what you are doing!!
Quit cheaping out and call a Liebert approved service company and quit driving the HVAC trade's name into the dirt!
You picking up any of these inconsistencies,Saint, or are you asleep at the wheel??

Semper fi and all, I mean you no harm , but you are well beyond your limits and too deep in the woods to know it.

[master mechanic]

I second that atmosphere

[storyusmc]

Originally posted by atmosphere
My stars, man, you've gone from a condensor fan motor and coil that is clean to a water cooled unit with a regulating valve!!
I sure hope you aren't hustling anyone into thinking you know what you are doing!!
Quit cheaping out and call a Liebert approved service company and quit driving the HVAC trade's name into the dirt!
You picking up any of these inconsistencies,Saint, or are you asleep at the wheel??

Semper fi and all, I mean you no harm , but you are well beyond your limits and too deep in the woods to know it.

Don't worry I did call Leibert. They said that it was more than likely clogging in the condenser. So today, I checked the valve because he said I should try opening it and closing it to verify that wasn't the issue. Which is isn't. Therefore, when I get time I will try a back flush. If that doesn't work. Then I will continue my efforts. Unfortuanatly, I work the Midnight shift so it's not like I can call right away and get someone. I am not going to have Leibert send a text to have someone wake up and talk to me about it when I can just knife it off.
As far as you statement of"I sure hope you aren't hustling anyone into thinking you know what you are doing!!" I think you were out of bounds with that. I am not saying that I am a 20yr veteran but I know how to ask questions before going all out. See you later

[The Saint]

I agree with you storyusmc. Now we know that it might be in the condenser section

[storyusmc]

Yep. At least I got a better responce from you that from atmosphere. All he did was cry about what steps I took and didn't even bother saying what he thought the issue could be. I don't trouble shoot package units enought to know everythign about them but I will. Thanks again for you help.

[hvacpope]

I guess you are a maintenance man trying to learn HVAC, well bud you picked the wrong unit to begin with, Lieberts are fairly complicated, you should call someone with experience and have them fix it, those units are very expensive and you don’t want to be the one ruin it.

[storyusmc]

Originally posted by hvacpope
I guess you are a maintenance man trying to learn HVAC, well bud you picked the wrong unit to begin with, Lieberts are fairly complicated, you should call someone with experience and have them fix it, those units are very expensive and you don’t want to be the one ruin it.

Nope you are wrong. I am not a maintenance man. I am just new to the industry. I thought I said that. Maybe you didn't understand when I said I wasn't a veteran. Only been in the industry for about 2yrs now and I am now starting to get my fingers dirty with package units. So I have a lot to learn about them. Sure anyone can read a book and pass the test but until you have to start op checking if and trying to figure it out it takes time and I am a noob in this area. I don't know how it is with you but I don't have anyone who has been in the industry who knows a lot about package units. That’s why I joined this forums. I can see that this going to be a waist of time when I can't even get a straight answer. FYI I found an old friend of mine who was in the business for about 30yrs and knew more about package units. He is the one that told me I should have the condenser coil back-flushed. Now I don't know how to do that or what chemicals I am going to use but I will tell you this I don't think I will be writing in the forum anymore. So peace out!.

[hvacpope]

Don’t take my words the wrong way, but you are not dealing with an everyday package unit here, Lieberts are way more than that. Before you backflush the condenser why don’t you get a hold of the service manual and read it a few times. How much time are you allowed to waste before you show some result?
You want to go somewhere with this post, start by posting unit model, pressures, superheat/subcooling, compressors amps draw, condenser delta T and check the approach between the condenser leaving water and the refrigerant.

[storyusmc]

Originally posted by hvacpope
Don’t take my words the wrong way, but you are not dealing with an everyday package unit here, Lieberts are way more than that. Before you backflush the condenser why don’t you get a hold of the service manual and read it a few times. How much time are you allowed to waste before you show some result?
You want to go somewhere with this post, start by posting unit model, pressures, superheat/subcooling, compressors amps draw, condenser delta T and check the approach between the condenser leaving water and the refrigerant.


No offence bro but don't take your words the wrong way? You flat out said I was a maintenance man. How else am I going to take it. Maybe a little insulting? Yea! Well thanks for your help I love being new to the industry and wanting to know more and having people right away judging me about what I know in knowledge. If I knew package units I don’t think I would need the forums. I am glad that I have a really hard unit to work on cause I will learn it but for those who are willing to dis-me I don’t need to hear your mouth. So please people don’t take MY words the wrong way.

[hvacpope]

What a freaking clown you are, there are quite a few maintenance men in this site that could spank you all the way to janitors room where you belong, you think that because you own a set of gauges and a couple of screw drivers you are something uumm, go back to that trade school and ask for a refund.

[storyusmc]

Originally posted by hvacpope
What a freaking clown you are, there are quite a few maintenance men in this site that could spank you all the way to janitors room where you belong, you think that because you own a set of gauges and a couple of screw drivers you are something uumm, go back to that trade school and ask for a refund.

Translation: I am the type of guy who would **** someone in the ass and wouldn't even give him a reach around. So now I will go spank myself and stick large pieces of piping in my ass and pray a rodent gets in.

[ericnyc]

If the unit has a strainer clean it, if theres a cwp (and of course it's running correctly or at all) clean that strainer as well. Water reg valve may need to be adjusted, bring that head down to 205, but watch your back pressure.

[atmosphere]

I helped you when I told you to call Leibert.
Either way, you got alot of free advice and even some apparent one on one professional help from Saint.
You've got nothing to kick about.

[storyusmc]

Originally posted by ericnyc
If the unit has a strainer clean it, if theres a cwp (and of course it's running correctly or at all) clean that strainer as well. Water reg valve may need to be adjusted, bring that head down to 205, but watch your back pressure.

Thanks. I will take another look into it. I cleaned out both strainers about 2months ago. Thanks

[storyusmc]

Originally posted by atmosphere
I helped you when I told you to call Leibert.
Either way, you got alot of free advice and even some apparent one on one professional help from Saint.
You've got nothing to kick about.


I know that you did help. I did call them. Thanks

[esornivram]

Originally posted by storyusmc

Originally posted by hvacpope
Don’t take my words the wrong way, but you are not dealing with an everyday package unit here, Lieberts are way more than that. Before you backflush the condenser why don’t you get a hold of the service manual and read it a few times. How much time are you allowed to waste before you show some result?
You want to go somewhere with this post, start by posting unit model, pressures, superheat/subcooling, compressors amps draw, condenser delta T and check the approach between the condenser leaving water and the refrigerant.


No offence bro but don't take your words the wrong way? You flat out said I was a maintenance man. How else am I going to take it. Maybe a little insulting? Yea! Well thanks for your help I love being new to the industry and wanting to know more and having people right away judging me about what I know in knowledge. If I knew package units I don’t think I would need the forums. I am glad that I have a really hard unit to work on cause I will learn it but for those who are willing to dis-me I don’t need to hear your mouth. So please people don’t take MY words the wrong way.
you stated you worked third shift, I dont know too many service tech who work THIRD SHIFT, I would take that as you calling yourself an plant maintenance man,however i could guess you deployed some where working mids? I have met many over the years teach me a thing or too. but your story is confusing to some who know their way around an mini mate system and without lots more data you leaving me at least in the dark, I DONT guess,, I find the problem and you havent given me much yet to tell,
like are the reheat heaters coming on? is this occuring during dehumidification and not cooling? is the steam generators cause voltage lows that could be giving problems, when was the last time the generatoors went into flush? did they restart making steam? did u add any salt?
I could go on for pages, but i hope yu understand why i am still ?????????????? ur story.
if its an tube and shell can you rod them to clear em out? mbr

[Edited by esornivram on 09-15-2006 at 12:32 AM]

[madhat]

If the Strainer(s) are real dirty remove and clean them, reinstall, restart unit and let it run for 30 to 40 minutes. Shut down the unit and reclean the Strainers. Reason for doing this is the flow in the piping will pick speed and sweep trash into the clean strainer. PS if you have Glycol in the system, and the strainer is plugged your going to need a contractor who knows how to clean up a Glycol system.

[madhat]

Originally posted by hvacpope
Don’t take my words the wrong way, but you are not dealing with an everyday package unit here, Lieberts are way more than that. Before you backflush the condenser why don’t you get a hold of the service manual and read it a few times. How much time are you allowed to waste before you show some result?
You want to go somewhere with this post, start by posting unit model, pressures, superheat/subcooling, compressors amps draw, condenser delta T and check the approach between the condenser leaving water and the refrigerant.

Actually I'd rather work on a Liebert anyday rather than anyones water source heatpump. Lieberts Engineering is right on the money, there is no slop in their design. PS perfect discharge pressure for Liebert is 225 discharge pressure, notice Scrolls may pop up to 300 psi on start-up, then slowly settle down, especially if the unit was shut off via the disconnect without a pump down.

[mfi]

Oh well, I guess I should shed a little light on the subject at hand. I work the 8 to 4 in this building. We are required to trouble shoot and most times fix all these units. Problem is our union school does not teach this, so we are on our own. We have kept about 100 of these in various sizes running for 15 years. When it gets to the point that we have to call in a contractor, we do. This happens mostly with the larger units, 20 tons and up. The ceiling units are usualy no problem. Here in NYC we are called Engineers, it's just a name, we didn't invent it. We are expected to know the whole building and almost everything in it. My last job was running a 15000 ton chilled water plant, no package units at all.But through studying on my own and this site I have picked up quite a bit. I encouraged Story to use this site if he got in trouble and needed some answers as I do. I hope he still will.

[esornivram]

Originally posted by mfi
Oh well, I guess I should shed a little light on the subject at hand. I work the 8 to 4 in this building. We are required to trouble shoot and most times fix all these units. Problem is our union school does not teach this, so we are on our own. We have kept about 100 of these in various sizes running for 15 years. When it gets to the point that we have to call in a contractor, we do. This happens mostly with the larger units, 20 tons and up. The ceiling units are usualy no problem. Here in NYC we are called Engineers, it's just a name, we didn't invent it. We are expected to know the whole building and almost everything in it. My last job was running a 15000 ton chilled water plant, no package units at all.But through studying on my own and this site I have picked up quite a bit. I encouraged Story to use this site if he got in trouble and needed some answers as I do. I hope he still will.
iom manuals and they are very good explanations, its simple to work your way around and learn these machines, dont rush but always think of big picture before i dive in,
oh and here the building inspectors require an permant mounted access for the service man, 30 inches of unobstructed area or platform,

[chefid]

if the side panel on some units are removed the air wont pass the condenser coil and the unit will trip on head pressure

[esornivram]

Originally posted by chefid
if the side panel on some units are removed the air wont pass the condenser coil and the unit will trip on head pressure

air?? across condenser coil????

he is having problems with an water cooled unit,

[atmosphere]

Howsabout someone put this thread to bed with a shovel already??

[The Saint]

Let's finish this thread! It's getting nowhere. Let's just wait for storyusmc's final message

[storyusmc]

Bump

[flange]

just read the initial post. hes got 82 entering and 140 leaving. this indicates low flow through the condenser, be it air or water cooled. since it is water cooled, strainer would be first place to check, valves open? pump running? bet its a strainer issue.