Hi all. Purchased first excavator last year to use on our farm. All seemed like a good purchase. Replaced oil and all filters, blew and cleaned everything out as it was fairly clogged up. Everything going well until it warmed up and found out it had an air con issue. Pipes would freeze up after using for 15 minutes. Local air con guy came out and said it was a thermostat issue. I’m not sure how many people have taken out the air con system before, but bloody hell who designed this. Had to take most of cab apart to get it out. Evaporator was clogged. Cleaned it, replaced thermostat and reinstalled.Took days. Almost cried when pipes froze up again. Air con guy doesn’t have any other ideas. I’m hoping someone can help me out here before it warms up again Thanks in advance Paul
You really need to start from scratch. Do you have gauge and a vac pump? Gauge readings will tell you everything you need to know.
Thanks for the quick reply. No I don’t, but my air con guy put his on and it all seemed ok, had to remove gas to take air con out of cab then re gas. is this what you were meaning?
Where are your pipes freezing up?
In the cab about150mm or 6 inches before it goes in under seat
It sounds like your expansion valve may be bad. You can read that on a gauge set.
Thanks. Could a faulty evaporator be a potential cause of this?
In the absence of a serial number I've taken a stab at an FJX prefix. Hopefully this picture will look like your machine. If not, post your full serial number. Which line is freezing, the one going to or the one coming from the evaporator? And can you indicate on the picture where the freezing starts? If you have a random point on the hose with frost on one side and "warm" on the other it's a sure sign of an internal restriction in the line.
Hey Cmark it’s GBJ01228 I think, just gone dark here, though your picture looks similar or the same. Pipe is freezing in between 1 and 16 just before it goes into air con. If I remember correctly it was frozen all around pipe Cheers Paul
So here's the official picture of your machine. On the face of it and without being there to diagnose it on the spot, I would say that you have a restriction in a line. Maybe a kink or the hose liner collapsing. The restriction should be right where the transition from hot to cold is. The hot side will be upstream and the cold side downstream.
Thanks Cmark. Hopefully this is what it is. It is on a hard line not flexi. Should a gauge show up a restriction or blockage?
Yes
Just a thought. Your machine is 8 years old. A question - Did you replace the dryer (#9 on Cmark's illustration in post #10).? It probably needs it by now. I'd suggest to do a full evac and recharge of the system using the correct weight of refirgerant (see sticker on cab door frame for the amount) and the appropriate amount of PAG oil for the compressor.
Sounds like to me your expansion valve is defect, when this valve does not open will start freezing yournlines up, when you do a aircon service and watch your gauges, they should drop a little as it recycling the old refrigerant out, then you know your valve is working,
Yeah, thats my thought also.
Not a bad idea to change the dryer, but the dryer only would need replaced if, you have a fowl smell when a.c. is running, too much condesatation in system, or if you open up the system when changing parts, like I said sounds more like your expansion valve
We change dryers in all our equipment a/c’s as part of the annual service. I’d stand corrected on this but I don’t think that a plugged dryer would cause a smell because only the refrigerant flows through it, not the air that goes into the cab from the evaporator.
Nige, most certainly, your dryer is a filter which refrigerant circulates through. If the dryer fails in anyway, it is possible to get a lot of moisture water condensation in your lines, thus over a long period of time, will cause a funky fowl moldy oder..
Seriously??? You forgot the emoticon. The only dryer failure that could "possibly" cause any odor, albeit briefly, would be an external rupture, and the odor would be at the point of rupture (outside the cab).
And, the dryer should be changed at any system open, due to low price. How many of you have had to completely disassemble a system when the desiccant bag has ruptured and sent desiccant balls through the whole system. As they say, "an ounce of prevention..."
Thanks guys. I will try anything to not have to pull the air con back out from under the seat
Hi all, thanks for everyone’s help, my air con is fixed, after taking cab apart again So looks like the previous owners bypassed the thermostat, rather than taking cab apart to fix, that’s why it looked like new thermostat wasn’t working. Also replaced the tx valve, evaporator and condenser dryer while we are at it. Hopefully staff happy in the middle of summer now. Thanks again for everyone’s replies