Keeping cab cool

[Graham1]

I'm operating a Cat 320 at present and struggling to keep the cab cool. It is only 28C outside, bright sunshine, but the air conditioning is going full on to keep inside at 22C. Have to have door and windows closed because lots of dust, but I'm working in a cold draft and the fan going flat out is starting to get to me. What do you guys do in hot places to keep the cab cool?

 

[CM1995]

Is the A/C system running properly? 28C is not that hot, at least for what I am used to.

The Cat excavators that I have run have all had pretty good A/C systems, same with my D5G. The 420D's A/C system is lacking but the cab also has a lot of glass.

If the A/C system is charged, coils clean, filters clean, etc - you might want to try adding some window tinting. I am thinking about tinting the doors, side and back glass on my 953.

 

[buckfever]

I'm not a 100% sure on this but I think the recharge kits that you can buy a the auto stores will work on machines. Your a/c might just need recharged. Tinting also make a huge difference. Don't need really dark tint just enough to filter some of the sunlight.

 

[Steve Frazier]

If the A/C needs charged it means it's leaking and will need charged again if you don't repair the system. The first thing I'd do is make sure the condenser and radiator are both clean so that there's a good air flow over the coils. It won't cost you anything but a little time with a water hose. After that you could check that the ducts in the machine are fully open and the evaporator is clear. Again, just a little time involved and no special tools needed. Finally, it may be low on gas as has been mentioned. Listen for the compressor kicking in and out frequently, this would indicate a low gas level. Again, you can add freon but unless you find the leak you'll be adding it again.

 

[Bluetop Man]

Since it appears from your post that the cab a/c filters are not on your radar, you probably haven't checked them. They, or it, should be behind the seat somewhere. Dirty filters are the single most cause of decreased a/c output around dirt work. If the output is stable and not slowly decreasing at it would with a leak, the filters may well be the culprit. It's like night and day how much cooler it can be after replacing some really dirty a/c filters. Good luck. Ain't nothing worse than a sweaty hot hoe. :drinkup

 

[Willis Bushogin]

I bought an older 1998 Cat 320 (in 2001) It was one of those real hot summers. I was lucky and found a ex Cat mechanic that worked it all out. It was the fan motor under the seat, he had to tear all that stuff apart to get to it, what a mess. For some reason I thought the cabin air filter was located on the outside, behind the cab, under a panel
I agree with all the comments, except washing the radiator and condenser out. I did this on a dump truck and put it to work on a dusty job and the dust from the road, turned the radiator to a muddy mess. I use air pressure and not high pressure, I have a piece of tubing, with a hole drilled in one side of it, I hook the air hose to it and fit it between the condenser and radiator, I can blow out both directions..

As stated, look at the a/c compressor and make sure its engaged and staying engaged. If the pressure is low, the low pressure switch, will limit the operation
If you get to much freon in it, the high pressure switch will limit the operation
could be the dryer stopped up
I think the Cat system, has a expansion valve, it could be malfunctioning, just taping on it sometimes will correct it (for a while)
Bottom line, Im trying to think of that phrase that Willie59 uses, something like a mechanic is priceless
This could be very simple and iit will take a A/C mechanic to put his gauges on it, he can tell you whats wrong in a few minutes. Do what you can yourself then call someone, it will save you money

OK Im finished

 

[willie59]

but I'm working in a cold draft and the fan going flat out is starting to get to me.

Your description leaves a bit to interpretation. The way I take this, correct me if I'm wrong, is that fan motor is running full tilt but at best you get a cool "draft" from vents. If that's the case, sounds like the air box is seriously restricted, possibly air intake filters, but more likely, I can't count the number of excavators that I've had to rip the guts out of the cab to get to the heat/AC box, get it uncovered, and find the evaporator coil completely covered with brown muck blocking air flow.

 

[Willis Bushogin]

Your description leaves a bit to interpretation. The way I take this, correct me if I'm wrong, is that fan motor is running full tilt but at best you get a cool "draft" from vents. If that's the case, sounds like the air box is seriously restricted, possibly air intake filters, but more likely, I can't count the number of excavators that I've had to rip the guts out of the cab to get to the heat/AC box, get it uncovered, and find the evaporator coil completely covered with brown muck blocking air flow.

My whole air box was stopped up with dirt and crap, but my fan motor was not working properly, electrical part, making funny noises, not turning up to full speed all the time. I wasnt getting a full flow
Sorry I wasnt plainer
Thats what I meant, he needs to get someone like you, that works in this stuff all the time, Im just a jackleg, that learns from all your comments especially
Good going Willie

 

[willie59]

Yes, many aspects to troubleshooting AC system Willis, as noted in previous comments. For sure putting gauges on system will tell you a lot about system operation. But if the vents just aren't blowing air, hot or cold, very possibly a big mud pie sitting on evaporator coil. This was the evap coil on a Case CX210 I worked on. Dated July 14, 2011 in East Tennessee, understandable why I had to tear into it.

 

[theironoracle]

Get a thermometer an put it in the a/c vent what is the temp? Last 322 heater a/c problem i had to fix was the door in the blower box had broken off, the motor was turning the shaft but the door that directs the air from a/c coils or heater coils had fallen off. I was able to rig it to close off the the a/c so the customer could keep his cab defrosted without removing the entire unit to repair correctly. Then he got back to production so he could pay the bill..

 

[Graham1]

Thanks for all the replies. I think the real problem is the air is coming out cold, but not really cold like air conditioning should, so the system probably needs recharging, but as it is a hire machine little chance of that happening. On the upside I have tried some car window blinds that sucker on to the glass and these make a noticable difference. I've also found the filter behind the seat and it was absolutely covered in muck. Removing the has greatly helped the airflow.

 

[Willis Bushogin]

when all else fails and you cant get the mechanic, blow the system out and get one of those freon recharge kits and shoot some freon it there. Im no A/C mechanic but I do my own work and if I get caught without my guages, I use these kits and just keep feeling of the steel fittings coming out of the compressor. One should be warm/hot and the other cool/cold. I just keep adding freon until the cool line gets cold, then stop and see how it does
A set of cheap guages, cost about $50-$60, it would be a good investment for you
But you have got, a stopped up mess in the picture, clenaing it out will help
As I said before Im not a mechanic, Im a jackleg, and I graduated with high honors, from the college (not school) of hard knocks

 

[JCLAY]

Sounds like it needs to be cleaned to me. Filters and components can get a lot of "mud" caked up on them like the previous posts say. A little tlc is probably all she needs.

 

[JustLogIt]

We have 3 Cat 320s and have blend door problems on all three. There is a little plastic "***" on the blend door inside the heater/AC unit that the servo-motor turns to regulate air flow. When it breaks, you're stuck with whatever position the door is in. It could be blowing all cold, all hot, or just warm.

Not fun to fix, but pretty miserable if it isn't working right

 

[shaneod]

Hey i drive a Cat 320D ex and it seems my evaporator coil is filthy. How do i get to it? I've taken off the shelf and cover behind the seat but i couldn't figure out what to do. I get a cold draft from the vents but no power. Filters are clean so i think it just needs a clean out. Please help...very frustrating!! Thanks

 

[bigshow]

Aside from fixing the a/c here's a few things I do to keep the cab cooler, tint the side and back windows, like you said hang the shades, and hang an umbrella off the hand rail by the cab, keeps the sun from beatin on the roof and shades your left arm too. I sometimes open all the engine compartment doors if its real hot, it lets so e of the heat out and and keeps it from cooking the cab. I don't like/use a/c so this is what I do to keep comfy.

 

[kbeen]

Graham 1 you might want to check your heater water lines where they come off the engine. if your machine has shut -off valves you can close the water flow off during the summer time because the water valve in the cab will usually start letting some hot water get by it and heat up the heater core so that you are blowing air by a hot heater core and the evaporator core. you can drop the a/c temp. several degress by closing the water valves off. good luck.