# A/C stopped working on Kioti CX2510HST Cab



## Quinn the Eskimo (Dec 20, 2021)

_Was heading down the road in hi at about -15C when my cab suddenly fogged up. I noticed the light on my A/C button was out. Turned it off, on, off, on etc and nothing. Got home and lifted the hood. Belt is turning the compressor. Pulled the fuse and it looks ok, but I’ll check with a meter.
Is there a protection mechanism built in for cold weather or something? _
Thanks!


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## Hacke (Feb 22, 2011)

I doubt that there is an A/C-system that works at -15 °C. You need heat to get rid of the fog. Full heat, no recirculation and a small ventilation opening (window, for instance).

Check that there is no snow or ice at the air intake.

If the fog is a bit greasy/sticky and/or you can feel a slight smell of curry powder, chanses are that the heater element is leaking, vapourised coolant is mixed with the hot air and is condensed on the cold glass.


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## Tx Jim (Jul 28, 2020)

Ditto I think I would be wanting heater not AC to operate a -15°C temperature


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## The 203 (Apr 27, 2020)

Tx Jim said:


> Ditto I think I would be wanting heater not AC to operate a -15°C temperature


If it works like a car the AC pump works to dehumidify in the defrost mode. I know my pump in my jeep started knocking and would come on in defrost mode


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## Tx Jim (Jul 28, 2020)

To my knowledge tractor AC systems have no automatic defrost modes. It will surprise me if AC thermostat will allow AC compressor clutch to engage @ -15°C/5°F. 

I guess I could experiment tonight with one of my cab tractors if temperature gets as low as weather guessers are forecasting BUT I THINK I'll pass on that test & stay inside my hopefully warm barn.


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## The 203 (Apr 27, 2020)

Tx Jim said:


> To my knowledge tractor AC systems have no automatic defrost modes. It will surprise me if AC thermostat will allow AC compressor clutch to engage @ -15°C/5°F.
> 
> I guess I could experiment tonight with one of my cab tractors if temperature gets as low as weather guessers are forecasting BUT I THINK I'll pass on that test & stay inside my hopefully warm barn.


You are correct Jim
It was warmer out when the compressor came on in defrost cycle


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## Tx Jim (Jul 28, 2020)

So are you stating you tractors HVAC system has auto defrost capability built into system?


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## The 203 (Apr 27, 2020)

Tx Jim said:


> So are you stating you tractors HVAC system has auto defrost capability built into system?


I was going by how my h.v.a.c. system works on my truck. It should be the same. My tractors have the open-air system, no cabs on mine.  heats my innards. 😁


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## Tx Jim (Jul 28, 2020)

HVAC on my '80, '91 & '11 with factory AC don't have auto defrost. My knowledge of tractors newer than '11 is limited. It will be interesting to know if newer tractors have ""auto defrost" HVAC systems!


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## joninva (Aug 15, 2021)

I turn my heat all the way up, then turn on the AC and use the ac control to regulate the temperature, if my windows are fogging. You need to get it warm enough in the cab for the AC to cycle. And turn off recirculation.


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## Tx Jim (Jul 28, 2020)

That method is what I utilized on my '91 JD 4255 yrs back when I plowed in colder temperatures. But I classify that method is far from "auto defrost" that other poster mentioned.


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## Bob Driver (Nov 1, 2017)

Used to buy this stuff by the case to get the damn drivers out of the break room and on the road faster in the morning. Took away the "Waitin' on the windows to defog" excuse and actually saved money by offsetting the cost of the free coffee they were guzzling by the gallon.....


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## boatmoter (Feb 27, 2015)

my first check would be power & ground at the switch since the switch no longer lights up


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## Quinn the Eskimo (Dec 20, 2021)

So after leaving my machine parked overnight, and the outside temp coming up to about -10C, I started it up as I had to plow again. After the temp gauge showed a warm reading, I depressed the AC button on the dash and after a couple of blinks the light stayed lit and I assume the AC was operational, but I shut it off. I used it all winter last year without issue. I am thinking there must be a thermostat that disables the AC below a certain outdoor temp. No leaks, no antifreeze showing anywhere, no smell, just condensation initially when it shut down. Using the heater/defrost without AC engaged requires a higher temp on the control and also the fan speed set at 2 at least instead of 1. Running the AC definitely keeps the condensation in the cab better under control. I run the AC in my truck year round, not just for cooling in summer, but for heating and its dehumidifying properties in winter as well. I assumed my tractor would be the same but apparently not quite.


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## Busted Tractor (May 22, 2018)

Here is a temperature/pressure chart for R134A. Note that pressure drops to very low levels at low temperatures. Most tractor/vehicle system have a low pressure cutoff that will not engage the compressor if the pressure drops too far. This is supposed to protect the compressor. No pressure no refrigerant, no refrigerant movement, no oil movement = burned up compressor.
Operating the AC at low temperatures also freezes the evaporator.


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## Quinn the Eskimo (Dec 20, 2021)

Thanks for the information and explanation. Much appreciated!


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