Help on a HVAC unit

[hawk369]

Hey, I am a Mechanical Engineering student and am looking at doing a project comparing the different air conditioning set ups between any kind of backhoes. I have actually done an internship with Cat working on HVAC units. I am looking for any sort of comments on what operators like and don't like about the HVAC units ( this could be controls, temperature, blower speeds, fogging of the windows, ect...). I would like to get a different variety of machines in the conversation from cat, komatsu, deer, volvo, and case. I just would like to hear a comparison of the different machines to see what operators think is the HVAC set up in the cab.

I am trying to start a converstion in the Backhoes and Excavators sections too but since this is my first posts I cannot start a new thread only reply to them. I am hoping someone may take this an create a new thread for opperators to talk about what they like and dislike. Any comments would be greatly appreciated. Thanks!

 

[cummins05]

Hey, I am a Mechanical Engineering student and am looking at doing a project comparing the different air conditioning set ups between any kind of backhoes. I have actually done an internship with Cat working on HVAC units. I am looking for any sort of comments on what operators like and don't like about the HVAC units ( this could be controls, temperature, blower speeds, fogging of the windows, ect...). I would like to get a different variety of machines in the conversation from cat, komatsu, deer, volvo, and case. I just would like to hear a comparison of the different machines to see what operators think is the HVAC set up in the cab.

I am trying to start a converstion in the Backhoes and Excavators sections too but since this is my first posts I cannot start a new thread only reply to them. I am hoping someone may take this an create a new thread for opperators to talk about what they like and dislike. Any comments would be greatly appreciated. Thanks!

You have three posts now you can start your own threads at will

 

[alco]

Hey, I am a Mechanical Engineering student and am looking at doing a project comparing the different air conditioning set ups between any kind of backhoes. I have actually done an internship with Cat working on HVAC units. I am looking for any sort of comments on what operators like and don't like about the HVAC units ( this could be controls, temperature, blower speeds, fogging of the windows, ect...). I would like to get a different variety of machines in the conversation from cat, komatsu, deer, volvo, and case. I just would like to hear a comparison of the different machines to see what operators think is the HVAC set up in the cab.

I am trying to start a converstion in the Backhoes and Excavators sections too but since this is my first posts I cannot start a new thread only reply to them. I am hoping someone may take this an create a new thread for opperators to talk about what they like and dislike. Any comments would be greatly appreciated. Thanks!

Honestly, my biggest complaint would be the air vents that fall apart in short order as they wear. Another thing that I would love to see fixed, is on the rocker switch for the a/c.....or any of the other rocker switches for that matter......it seems the part of the switch that lights up always breaks out of the switch and leaves a rocker switch with a hole in it. As for the HVAC systems themselves, they seem to be pretty good all around in my books.

 

[John C.]

The biggest issue I have with AC in machines is that you have to tear the whole cab apart to work on any of it. Just getting to the filters means you have rip out all the consul behind the seat and usually the seat itself. Event the intakes are out the back of the cab into a bulkhead which usually fills with debris.

 

[surfer-joe]

I agree John C.

Servicing heavy equipment A/C units has been a pain in the behind for many years and from what I see, the engineers still have not figured it out.

But then, most owners and their maintenance departments haven't figured it out either. If you do not service and maintain the units on a scheduled basis, or with increased care in dirty conditions, they will fail on you in short order. Operators jamming cigarettes, pop cans, newspapers, and pieces of clothing into the vents or in front of the ducts don't help either. A filthy operator keeping a filthy cab will cost the machine owner a lot of money in short order.

I returned many systems to working order with just routine maintenance and care that the systems had never received before. Once in good operating condition, a few words to the operators, and scheduled maintenance on belts, bolts, filters and Freon will keep them running for a long time with little trouble.

 

[hawk369]

Hey, I am a Mechanical Engineering student and am looking at doing a project comparing the different air conditioning set ups between any kind of backhoes. I have actually done an internship with Cat working on HVAC units. I am looking for any sort of comments on what operators like and don't like about the HVAC units ( this could be controls, temperature, blower speeds, fogging of the windows, ect...). I would like to get a different variety of machines in the conversation from cat, komatsu, deer, volvo, and case. I just would like to hear a comparison of the different machines to see what operators think about the HVAC set up in the cab.

 

[hawk369]

Hey, I am a Mechanical Engineering student and am looking at doing a project comparing the different air conditioning set ups between any kind of backhoes. I have actually done an internship with Cat working on HVAC units. I am looking for any sort of comments on what operators like and don't like about the HVAC units ( this could be controls, temperature, blower speeds, fogging of the windows, ect...). I would like to get a different variety of machines in the conversation from cat, komatsu, deer, volvo, and case. I just would like to hear a comparison of the different machines to see what operators think about the HVAC set up in the cab.

 

[hawk369]

I am actually looking for comments that relate back to specific tractors. Anything that needs to be fixed on specific tractors would be really good, especially Caterpillar tractors.

 

[hawk369]

I am actually looking for comments that relate back to specific tractors. Anything that needs to be fixed on specific tractors would be really good, especially Caterpillar tractors.

 

[digger242j]

Hawk, I moved this here to the General Industry Questions Forum, and I'm going to remove the other identical threads from the other forums you posted them in. Having three identical threads in three different forums can only confuse things.

On edit: I hadn't realized you'd sprinkled this question in posts over five different threads. Your most recent thread, and the earlier question and replies are all consolidated here now. Please don't do that any more. :bash

And welcome to HEF.

 

[dayexco]

i really can't speak for tlb's....but for excavators/front end loaders, and what i say here will probably parrot comments made by operators/owners of all kinds of different equipment.

don't bury the heater/ac fan. i may need to get to it and change a motor, relay..i don't want to spend 2 days disassembling/reassembling my machine to make that repair. one failure on many manufacturers...in the heat mode...duct it towards my feet...heat rises, you get that heat down by my feet, get them warm, the rest of me shouldn't be a problem. good luck on your study!

 

[RTSmith]

Hawk, Can't speak for the E, but on my 420D there just isn't enough air volume. Here in the south, the cab is like a greenhouse in the summer, and while the air temp at vents is cool, there just isn't enough of it.

 

[hawk369]

Thank you for the comments. This is real helpful. Keep them coming please.

 

[heavylift]

The thing about A/C in equipment is.... as with backhoes ... you are setting in a seat surrounded by oil that is 200 degrees or hotter....
Plus for some odd reason... many companies are now painting the cabs BLACK
Now if the controls heat was vented to the outside...in a close loop as not to exhaust the A/C air...

As for vents... Personally I would rather see more of them up high... as well as the return air....up about midway.... this may keep the cab filters cleaner
Why ..nothing like vents stirring up dust all day long... the cab may be clean but there is alway a bit of dust to be stirred

 

[hawk369]

The biggest issue I have with AC in machines is that you have to tear the whole cab apart to work on any of it. Just getting to the filters means you have rip out all the consul behind the seat and usually the seat itself. Event the intakes are out the back of the cab into a bulkhead which usually fills with debris.

John, what Caterpillar cabs do you have this problem with?

 

[hawk369]

Does anyone have any thoughts on what could be changed to make the cabs and air conditioning better?

 

[John C.]

Basically all the excavator cabs of any manufacture. They are all add on units that basically were engineered into the machines just before they go into production. I see no reason the evaporator has to be inside the cab. There is always space behind the cab either above the house sheet metal or covered below it. I've installed a fair amount of Red Dots on loggers and never had the problems that I've had with factory installs.

The problem I've seen on loader backhoes is that they don't figure in the input from all the extra glass they install now. The radiant heat from all the windows is just a killer in those.

There also needs to be a kill switch so that when doors and windows are open, only the fan works. No use heating and cooling the outside. I've can't tell you how many times I've driven to a job site on an AC or heater complaint and found the excavator operator with the front window up and the system maxed out.

 

[Lee-online]

I work on all kinds of Cat and the only real complain is the so called quick disconnects. When i need to take a cab off there is nothing more frustrating than the quick couplers being seized. These couplers are a fine thread and stay wet most of the time and they just seize over time. Simply using anti seize should help but a better design would be better.
Now instead of just unscrewing them, i have to evacuate the system, disconnect a hose or two. Then to put it back together i have to pull a vacuum to try to remove the moisture from the system , add the oil that came out, charge it and replace the dryer.

as far as the BHL. Only problem is they are not efficient enough with all the glass.

 

[qball]

quite frankly, i prefer open cabs.

 

[reaper020]

i agree with everyone the ac units are way under powered. and filters are hard to access some newer macines are getting better. komatsu 200 excavator has a side door you can open to get at the filter. would be nice to have a way to blow out the filters like reversing the fan or a built in air supply. john deere 310 backhoe filters could have easyier to remove tabs but the filter location is good. they last about a week then are clogged up and air flow is almost none existant. I have also noticed that the internal components get gummed up from other operators pulling filters and leaving them out for to long would be nice if there was a way to acess and wash out the internal parts to increase air flow again. not sure if it would be better or not but the komatsu 200 uses a foam filter that is washable. seems easyer to clean as the company i work for never wants to replace the paper filters.