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Grove tms9000e dual evaporater

HotInOkc on Wed August 03, 2011 11:56 PM User is offlineView users profile

Year: 2009
Make: Grove
Model: Tms9000e
Engine Size: 10.8l
Refrigerant Type: R134a
Ambient Temp: Unk
Pressure Low: Unk
Pressure High: Unk
Country of Origin: United States

So I'm having a tough time
Convincing my employer that this dual evporater ac system is not performing adequately.
Ive been told the system
Was evaced and recharged but after about 6 hours of use it has quit
And was never adequate for oklahomas 110 degree heat.
Is it possible this cranes condenser isn't cooling enough?
Perhaps it's clogged?

Here is a page with a similar crane
The condenser is on top of the lower cab
In front of the beacon lamp.
http://www.cranenetwork.com/details/Grove/TMS9000E/158330/bU5xd3/

bohica2xo on Thu August 04, 2011 2:28 AM User is offline

So where are the two evaporators? One in each cab?

Where is the compressor mounted?

Have you checked the fans in the condensor unit?

-------------------------
"Among the many misdeeds of the British rule in India, history will look upon the act of depriving a whole nation of arms, as the blackest."
~ Mahatma Gandhi, Gandhi, An Autobiography, M. K. Gandhi, page 446.

HotInOkc on Thu August 04, 2011 7:16 AM User is offlineView users profile

Yes there arE evaporators below each cab. This crAne has only one engine.
The compressor is just inside the engine bay behind the driving cab in the center.
YeH condenser fans work, it has two fans. Run quite hot
Thanks for the prompt reply

mk378 on Thu August 04, 2011 9:22 AM User is offline

Worked for 6 hours after charging it may have leaked out. You get all the cooling action from the last few oz of refrigerant. Once those are gone you don't get much cooling but it would still take a long time afterward to continue to leak all the way down to zero so the compressor doesn't engage.

Heat exchangers clogging up with dust is always a big problem in off-road machines of any sort. The first system to suffer will be the A/C, long before the engine overheats.

I'm guessing it is designed for only one cab to be in use at a time; the evaporator fan in the other cab should be turned off. That will cause the TXV for that evaporator to close down and most of the refrigerant flows to the other cab.

bohica2xo on Sat August 06, 2011 12:51 AM User is offline

Oh boy. That looks like a plumbing nightmare. With the compressor mounted on the engine, and the condensor on the roof, plain old trucks had troubles with leaks.

Adding a second evaporator 20 feet away would be just about the ultimate dual system oil balance nightmare. Add to that the fact that the rear evaporator is several feet above the rest of the system, and you have a very difficult to manage and maintain system.

What sort of rotating joints are used to get the refrigerant past the rotation of the boom? does it rotate 360 degrees? that would be the first place I looked for the leak. You may have more than one leak too.

Grove used to have some great engineers. Guys that understood the rear cab should have had a stand alone system with a hydraulic powered compressor. I wonder what happened? That mess looks like it was designed by somebody Fiat fired for showing up drunk every day.

B.

-------------------------
"Among the many misdeeds of the British rule in India, history will look upon the act of depriving a whole nation of arms, as the blackest."
~ Mahatma Gandhi, Gandhi, An Autobiography, M. K. Gandhi, page 446.

HotInOkc on Tue August 16, 2011 9:16 PM User is offlineView users profile

Well it turns out,the pressure switch quit. No leaks thank goodness. The evaporators both work At the same time regardless if a switch is off in one cab or the other. I've yet to clean out the condenser but intend to soon. Apparently the system had too much oil in it and is running cooler than it ever has but unfortuneately it can't keep itlower that 90-100 degrees in cab. My main concern right now is making the upper stay cool. I'm suspecting that the tint is absorbing a load of heat and isn't helping matters none.
I plan to replace or remove this tint
I plan to build an acrylic box to hold two tornado fans to force air into the recirculate suction inside the cab as the stock fan system doesn't blow hard enough to keep up with the greenhouse heat.
I also plan as I said before to clean out condenser

With that in mind, I must mention the pressure side of the evaporator isn't too hot to touch so I suspect the condenser is doing all it can.
Thanks for all the professional help. Does anyone think my super charge of the recirculating port is futile?

HotInOkc on Wed August 17, 2011 9:59 PM User is offlineView users profile

Operating temps are
Lower cab = 64
upper = 58

bohica2xo on Thu August 18, 2011 1:07 AM User is offline

Increasing evaporator airflow may improve comfort, but it will not lower temperatures. In fact the discharge air will probably get warmer.

If the system is equipped with TXV's, shutting down the blower on one evaporator will reduce it's refrigerant flow quite a bit. A way to shut down the fan in the lower cab would improve cooling to the upper cab if there are TXV's on both evaporators.

Adding airflow to the condensor may help. Make sure it is clean, and that the fans are working properly.

Are there service ports in the upper cab? Any system pressures will be helpful with diagnosing this system.

B.

-------------------------
"Among the many misdeeds of the British rule in India, history will look upon the act of depriving a whole nation of arms, as the blackest."
~ Mahatma Gandhi, Gandhi, An Autobiography, M. K. Gandhi, page 446.

HotInOkc on Thu August 18, 2011 2:59 PM User is offlineView users profile

In the meantime till I get some
Gauges here's a few pics from the crane I took of the evaporators

First one is of the lower cab
You can see the txv I think just tothe left of that line clamp
Photobucket Pictures, Images and Photos

A different view
Photobucket Pictures, Images and Photos

Here's the upper. Nevermind the plastic, it's holding the air flow inside the box. I don't see a txv here, could it be inside? Could it be a single txv?
Photobucket Pictures, Images and Photos

Another upper angle
Photobucket Pictures, Images and Photos

Edited: Thu August 18, 2011 at 3:06 PM by HotInOkc

bohica2xo on Thu August 18, 2011 5:20 PM User is offline

Two TXV system.

That rectangular block is the TXV for the upper evaporator.

Do you happen to have a couple of thermocouples? Looks like the plastic bag could be removed to mount them on the lines to the upper evaporator easily enough.

Once you are ready to close that hole up, buy some presstite tape.

B.

-------------------------
"Among the many misdeeds of the British rule in India, history will look upon the act of depriving a whole nation of arms, as the blackest."
~ Mahatma Gandhi, Gandhi, An Autobiography, M. K. Gandhi, page 446.

mk378 on Fri August 19, 2011 9:51 PM User is offline

As the pictures show, it's a simple setup with tees to the other cab. The tees really should be in the engine compartment, closer to the compressor and condenser, to minimize line length. Especially considering that the operator is going to spend most of the time in that cab doing crane stuff, instead of driving down the road in the front cab. But that's a major modification. Suction lines also look too small for their length.

Heavyhook on Wed August 31, 2011 9:03 AM User is offline

I totally understand what your dealing with. Iv'e been running Cranes for the past 35 years. The last 25 having been in Dallas running mobile cranes in the Crane Rental industry. Unless you have spent a summer sitting in a cab that is 90% glass you have no idea how hot those cabs are. I have been running the GMK style all train cranes for the past 15 years- GMK5240. The company I work for Davis Crane Service takes our cranes over to a commercial shop that specializes in trucks and other heavy equipment to have the A/C systems installed. I'm not sure of the tonage or BTU size of the units but they are the most powerful ones that are commercial available. Even with those units the cabs do not stay cool, each cab has a completely separate system. Their is so much radiant heat coming Thur the large surface are of glass its hard to transfer that much heat out of the cab. What I have found that works better than anything is to get some of the small retractable blinds made to use in autos. Their normally about 10" wide and extend out 12 to 14 inches long and are held in place by suction cups. They sell for 2 or 3 dollars each, doing that along with swinging around where your boom will shade your cab will help more than any thing else ( which I am sure you already do ) . Any thing you can do you limit the thermal transfer of heat from the sun shining on to or Thur the glass on your cab. Old school was placing a piece of plywood over your skylight when your in a situation where you can work without looking out the skylight. One other thing keep your engine RPM set between 1200-1500. the liquid freon on your cranes system has a long way to travel from the lower condenser and up Thur the hydraulic swivel to the upper cab evaporator. Plus the swivel has hot hydraulic oil circulating Thur it, so I am surprised it works at all. I saw a set up on TMS865 and TMS1300 Grove cranes back in the early 90's that was rigged up by using a hydraulic motor to run the compressor. They had a Master Mechanic that could rig up just about anything and had put togother the systems out of piece meal parts. They worked well but you still have to limit the sun shine entering the cabs and will always be the most effective thing you can do to help the A/c you have work most effective. Back in the 80's I ran tower cranes here in Dallas and I would use foil over the side cab windows which helped a lot. Hope this helps. Keep your whip line tight and watch out for those power lines (# 1 killer of crane operators and workers around cranes!!!) Doug /Member Operating Engineers Local Union 178

Edited: Wed August 31, 2011 at 9:09 AM by Heavyhook

ice-n-tropics on Wed August 31, 2011 3:48 PM User is offline

Okie,
From my designs and high ambient testing (128F and 1000 watts/m2 solar load) on military vehicles I learned the following:
1) hydraulic fluid cooling is critical to maintain compressor rpm. Hot hydraulic fluid can slow down the compressor 15 to 20% here in Dallas.
2) hydraulic fluid power can be inadeaquate if the pump or motor cavitates or pressure piping is restrictive.
3) A high isentropic efficiency compressor is necessary to obtain the max. BTU from the avaliable hydraulic power.
First prize is a scroll compressor with volumetric efficiency above 90%. Vane rotary is also high VE. About 20-25% more cooling is alaliable from the scroll for equivilant input power if a killer condenser is used.
Next is a Sanden wobble plate compressor,e.g., SD7H15, SD7H13, SD5H15 because the suction gas is not overheated before the suction valve and VE is 60 to 75%.
Worse VE is the TM type that preheat the suction gas due to crankcase routing of incoming suction gas prior to the suction valve and VE at 110F goes below 50%.
4) A monster condenser capacity is required and no engine hot air should reach the condenser air inlet.
5) Insulate the cab
6) Use nearly 100% recirculated air, not fresh!

Brad's advice is spot on to turn off the other cab blower.
Also reduce solar load.

These long plumbing systems with dual evaps. require about 10 oz. of oil which reduces the heat exchanger and compressor efficiencies. Stand alone systems for each cab are better performers. If the compressor was ever replaced, the AC system may have double oil charge.
Best regards,
hotrodac

-------------------------
Isentropic Efficiency=Ratio of Theoretical Compression Energy/Actual Energy.
AMAZON.com: How To Air Condition Your Hot Rod

HotInOkc on Mon April 02, 2012 12:34 PM User is offlineView users profile

Here I am back to bump my thread !! Lol

Ok, in response to the lat two posts, the compressor is operatedby the engine.

Someone mentioned the return lines are too small?

HotInOkc on Mon April 02, 2012 10:37 PM User is offlineView users profile

ive been watching this video series today.... anyone know of a more updated set of videos for troubleshooting in this manner?

http://www.youtube.com/watch?v=HztDhgyq6wc



this is the first time i posted from somewhere other than my iphone and just noticed the section below this one.....
off to spend some reading time there


EDITED:
does anyone know of a particular formula to determine the proper PT relative to humidity?
i keep seeing stuff like ambient x2 plus 50 for the pressure....(not here) well thats the max obviously, but ive also read that relative humidity comes into play (youtube series mentions it)
are PT charts specific to manufacturers?


we now have a 17 y/o and a truck mechanic certified from i dont know where, working for us now who do the a/c charging. wish i could have taken said class so i wouldnt be frowned on when i grab the equipment and go to town!.... (half joking)


so, i have a dual evaporator system which uses TXVs im told. If they both function at the same time (Drive lower without ever turning on upper, upper evap is cold too,((condensates,cold to touch)) fans off)
(Turn off lower power and function crane from upper, lower evap still functions((condensates,cold to touch)), no fans)(turning off ac switch regardless of opposite cab has theirs on and a power off turns off both acs) is there a procedure they should be following to ensure they are simulating a working environment?

should i drive this machine down the road 5-10 miles or operate the hydraulics extensively before making a charge?
should (dumb question?s? alert) they be charging the crane at a particular idle level (ive read 1500 for autos)?
should all the windows be open and in recirculate mode (upper only recirculates or doesnt, lower is only recirc)
should we charge with both ACs operating simultaneously? or will this cause freezing

can i block condenser flow to test to see if the unit is sufficient?

can i put valves somewhere in the lines to decrease waste( dumb question) to other evap?



sorry about all the dumb qs

i cant get these mechanics to tell me what they are reading at the pressures. noone likes being second guessed but something is being overlooked.

this crane is a hybrid and something isnt right. im willing to buy gauges, preferably the ones on the home page and do some research work myself but time hasnt permitted. 100 hour weeks and deliberate asshole dispatching is limiting my options. ive pissed off my salesman i think.....






Edited: Mon April 02, 2012 at 11:03 PM by HotInOkc

bohica2xo on Tue April 03, 2012 7:12 PM User is offline

You have two TXV's. If you shut down the blower on one evaporator, the TXV goes to minimum flow. Yes, the evaporator will still get cold, but will not ble flowing much refrigerant.

If you have enough cooling at road speed, I would run the crane cab system blower on max speed all the way to the job. Cool that cab down as much as you can on the way to the job. Once you bail out of the truck cab, shut the blower down in the unused cab. No sense wasting cooling capacity on an un-used driver's seat.

Engine speed is important because your compressor produces more flow at higher speed. 1500 rpm for testing is common. I presume you have some sort of Idle Up for operating the crane.

If you buy a set of gauges, connect them & run the engine at 1500, or the idle up that you use while operating. run both cab blowers on the highest speeds, for 5 minutes. Record the pressures & high idle speed - then post them here.

Do not block the condensor airflow. That can raise pressures very quickly, and you could already have pressures that are too high.

No need for valves, the TXV should handle this.

All dispatchers suck sweaty donkey parts. They can make your life hell. Take the fat chick in dispatch a big box of donuts & hope for the best...

B.

-------------------------
"Among the many misdeeds of the British rule in India, history will look upon the act of depriving a whole nation of arms, as the blackest."
~ Mahatma Gandhi, Gandhi, An Autobiography, M. K. Gandhi, page 446.

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