Need help finding locations of A/C compressor relay, low and high pressure sensor or does one sensor control both low and high pressures and evap thermistor location.
We need your help to supply a machine Serial Number in order to answer your question.
Model # 303.5C serial # CAT30335CCDMY03166
Please let me know thank
Thanks for the information. Check your messages for some info I think should answer all your questions. If not please ask any other questions back here.
hey Nige since we're on this topic.. FPK02319 304C CR just for giggles I got out my parts book.. I have as best I can tell a factory installed AC system but when I go into the parts book the only depictions I can find are the hoses and the dryer... can't find parts like condenser, compressor, evaporator, expansion valve... nada.. does cat have an addendum or something specific for the AC components
So you don't have the illustrations below.? (these are just a couple of examples) Is your parts manual OEM or "other".? If it is OEM what is the Cat Publication reference.?
thx Nige it is a cat book SEBP4462-15 using a couple part numbers I'd found elsewhere I looked them up in the numerical index in the back of the book and found the above pictures in my book as well... then I discovered the small section that shows the numbers I was interested in are not depicted specifically other than in the big HVAC box.. I think it says "not illustrated" at least I've got the part numbers for the pieces I need so that's a start.. taking the box apart is always fun but I've already done it a couple times.. my AC compressor crapped the bed so I plan on replacing it along with the condenser, dryer, expansion valve and evaporator.. then I only need to flush the lines.. seems to be different schools of thought on how effective flushing the condenser and evaporator are.. they're not stupid expensive so I'll just do that..
The latest iteration is SEBP4462-30, but even so your book should have at least the basics in it. All the AC system components should appear in the "Operator Station" section. The high-level Group Number appears to be 282-9305 Air Conditioner Arrgt. Apart from that, the AC compressor, lines, and condenser appear in separate groups.
You got it, cleaning the coils is a judgement call, based on the mode of failure and examination. If the compressor ate itself and shared that love everywhere, yeah, you may not be able to clean the coils. Prob a quick check is I think those little systems are fixed orifice, not TXV, so if you pull that, it will have a 'last chance' filter screen. If it's clean and intact, there is a good chance you are good on the evap. Condenser always needs a hard. If no TXV, you would not have a receiver, which is a receiver/dryer, and would catch any debris. But don't underestimate the lines! That rubber can hold particles. I prefer to shoot pigs through the lines and catch them so you can evaluate.
I've watched pigs getting shot through big pipelines... hard to imagine on the AC lines... where do you find such little pigs? when it comes to system orings are the cheap ones on amazon adequate or does one need to visit the auto parts store? it does have a receiver/dryer in the system mounted right by the condenser coil.. I was wondering if there might be filters in the system anywhere.. and how much crapola the dryer would catch from the compressor.. thx much for the input
Pigging AC lines is a daily practice. You can find/use many things from maybe no lint rag pieces, on up to pro pigs. Yep, can buy them in kits. Shoot em with N usually but comp air is probably fine if clean for these small systems. It's a total crapshoot on quality Orings!!! What you WANT is PTFE (teflon), but I am seeing many that are dyed but really just Buna-N POS! Honestly quality Buna will work, but China junk will crack quickly, they plan it that way to ruin America. Auto parts stores are wildly variable. Somewhere like NAPA will have you covered, Oreilly, I just don't know. If they don't tell you what they are, F em! You want PTFE and they like to just say "AC Orings". GM made that mistake decades ago on valve stem seals. If you have a receiver, NOT a accumulator, then you likely have a TXV, and the receiver will have the filter. It is a nice big filter. That layout is compressor - condenser - receiver - TXV. This is why looking at the condenser will tell you things. But the receiver should have caught 100% of the debris. I guess confirm what system you have.
cat part number is 176-1902 and they call it a receiver assembly so who knows
I'll go to finning to get the o-rings... should be a safe bet
Yeah, that appears to be a receiver. Easy to tell in the machine. Line from condenser goes right to it. An accumulator will be on suction side, after evap. Usually more like a pop can because it doesn't have near the pressure.
Foam earplugs work great for smaller lines.
Okay Nige here’s one for you Does cat have a build sheet for each machine on file? If so is it possible to research the part numbers of the various components installed at manufacture.. just curious as to what it would show in comparison to what the parts book says should be there.. Just thinking of my condenser, evaporator and expansion valve.. Could save a lot of hassle with return shipping and screwing around if you order what isn’t actually installed
Only at a high level, usually shows what options were fitted to a base machine. It likely would not show the level of detail you are asking about. In the case of AC there will only be one option. Either a machine has it or it doesn’t.
See the attached. The AC is part of the Cab Arrgt. Unless each line of Page 1 was expanded then it is highly unlikely the information would be useful for parts ordering purposes.
thx Nige.. always interesting stuff to look at.. just for giggles I started looking for a part number for the pressure switch (high/low) in the AC system.. it's located at the HVAC box in the cab, just off floor level by the expansion valve.. it's not mentioned in the "not depicted" section of the box and I finally found it shown in the AC line pages but no indication of a part number.. I did a google search for various expansion valves in other cat mini's and looked through the numerical section of the parts book to no avail..
I just worked on one and the pressure switches were at the compressor.
thx.. I know there's a switch built into the compressor but this one is marked in the picture
Do you physically have that switch present on your machine.? What was the Group Part Number in your Parts Manual where that illustration appears.?
hey Nige that I do not know... there are two connectors down by the compressor, one would be the clutch and the other I assumed would be for some type of internal switch in the compressor.. GP number is 267-4264 if that's what your asking and I believe the page number in my book is about 642... nomenclature is Lines GP air conditioner
It's a bit like we always say. Our local buses carry advertisements on the side for laundry detergent but that doesn't mean to say they take in washing........... Until you have physically verified the presence of that switch you can't assume it's there simply based on an illustration. Here is the illustration of 267-4264 on the electronic system. No switch.......... Here's a snip from the electrical schematic. See if you can find wires E554 Pink and 522 White. these are the ones that connect to the A/C thermostat switch.
don't know if I understood you correctly earlier or not.. when I said I wasn't sure about a switch I was referring to one being installed in the AC compressor.. the switch with no part number installed in the AC line that I pointed out in the picture that I'd attached earlier most definitely is installed in my machine.. as well as the thermistor that's clipped in the evaporator.. I've seen it when ever I've taken the side panel off.. as mentioned earlier it's a curiosity thing.. next time I'm in the vicinity I'll look to see if there's a part number on it..
Check wire colours and try to cross-reference them with what's shown on the electrical schematic. Also see whether or not you can find any numbers on any wires. The combination of number/colour should nail it down to a single option on the schematic.
Looks like white/brown and black/red