3000 Series A/C Issues
- Thread starter Silver_Knight
- Start date
- Views: 19230
tglass, here a is a thread that goes into it pretty well.
http://www.tractorbynet.com/forums/john-deere-owning-operating/125661-need-some-info-jd-cab.html
http://www.tractorbynet.com/forums/john-deere-owning-operating/125661-need-some-info-jd-cab.html
Yeah, that sounds like a good plan.
jenkinsph
Super Star Member
Silver Knight, just read the whole thread and can feel how exasperated you are. Can't blame you in the least, you paid for an ac that should work.
There has been some good ideas on trouble shooting this problem by other posters. If the air is bypassing the coil in the cab roof then the coil would get to cold causing the expansion valve to close or reduce the flow of freon until the coil temperature rises again. Without a proper airflow across the coil the expansion valve would quickly close again and repeat this cycling.
Another poster has mentioned to check the suction or larger low pressure line that returns to the compressor and condenser, if this line is too cold then the most likely problem is not enough air flow across the evaporator coil.
When the system is working correctly the warm air in the cab should be drawn through the evaporator coil. The evap. coil should collect this heat and at the same time the expansion valve bulb should sense this warmer temperature and hold the valve open allowing the freon to circulate almost continuously until the coil cools down to the lower temperature cutout. Also the condensor coil at the front of the tractor should get warm too especially where the refrigerant line enters the coil and should be cooled substancially by the time it exits the coil and returns the liquid to the cab. This high pressure line returning to the cab can be slightly warm to the touch or may feel the same as the ambient temperature. If it feels too hot then the condenser coil may have poor circulation and is not cooling or removing the heat from the system. In this case you may need the larger blower but I don't think that will be the case.
I would perform a few simple tests to better determine the problems you are experiencing. I use some high end test gear in my business but it isn't absolutely necessary to get a general idea of where your problems lie. I would start by purchasing a simple probe type temperature guage either a dial type or led type to take some temperature readings. Also a small roll of foam insulating tape ths should be available at a NAPA parts store or similar store.
Run tractor with ac temp dial to coldest setting and heating turned to coldest setting. On newer tractors this is turning both temp knobs in same direction. Set fan speed to medium, run tractor for 10 minutes.
Take these readings and write them down
outside air temperature in shade
cab temperature at mid height
temperature at inlet to box
temperature at outlets
Next find a place as close to the upper air box where you can measure the temperature of the refrigerant lines at a metal connection. You will need to get the temperature of both lines and should wrap insulating tape tightly around the probe and line to hold them together while insulating them from the ambient air to get a good reading. Do this individually to each line and
mark these down.
You should be able to buy the thermometer for about $15 bucks and tape for a few bucks, so well worth the investment. Post these numbers and we can give you an idea of what the problem really is.
Steve
There has been some good ideas on trouble shooting this problem by other posters. If the air is bypassing the coil in the cab roof then the coil would get to cold causing the expansion valve to close or reduce the flow of freon until the coil temperature rises again. Without a proper airflow across the coil the expansion valve would quickly close again and repeat this cycling.
Another poster has mentioned to check the suction or larger low pressure line that returns to the compressor and condenser, if this line is too cold then the most likely problem is not enough air flow across the evaporator coil.
When the system is working correctly the warm air in the cab should be drawn through the evaporator coil. The evap. coil should collect this heat and at the same time the expansion valve bulb should sense this warmer temperature and hold the valve open allowing the freon to circulate almost continuously until the coil cools down to the lower temperature cutout. Also the condensor coil at the front of the tractor should get warm too especially where the refrigerant line enters the coil and should be cooled substancially by the time it exits the coil and returns the liquid to the cab. This high pressure line returning to the cab can be slightly warm to the touch or may feel the same as the ambient temperature. If it feels too hot then the condenser coil may have poor circulation and is not cooling or removing the heat from the system. In this case you may need the larger blower but I don't think that will be the case.
I would perform a few simple tests to better determine the problems you are experiencing. I use some high end test gear in my business but it isn't absolutely necessary to get a general idea of where your problems lie. I would start by purchasing a simple probe type temperature guage either a dial type or led type to take some temperature readings. Also a small roll of foam insulating tape ths should be available at a NAPA parts store or similar store.
Run tractor with ac temp dial to coldest setting and heating turned to coldest setting. On newer tractors this is turning both temp knobs in same direction. Set fan speed to medium, run tractor for 10 minutes.
Take these readings and write them down
outside air temperature in shade
cab temperature at mid height
temperature at inlet to box
temperature at outlets
Next find a place as close to the upper air box where you can measure the temperature of the refrigerant lines at a metal connection. You will need to get the temperature of both lines and should wrap insulating tape tightly around the probe and line to hold them together while insulating them from the ambient air to get a good reading. Do this individually to each line and
mark these down.
You should be able to buy the thermometer for about $15 bucks and tape for a few bucks, so well worth the investment. Post these numbers and we can give you an idea of what the problem really is.
Steve
jenkinsph
Super Star Member
If you want to determine whether you may need additional condenser cooling, the easy way to do this is to run a water hose across the coil and see if the temperature drops significantly on the outlet air. If this is your problem the air should drop to about 50 to 55 degrees F.
Steve
Steve
OP
Silver_Knight
Silver Member
Actually, yes it does drop quite a bit. Ealier in the week I removed the radiator for the turbo and the batery so I culd get to the entire evaporator cor and cleaned it real well. I also put duct tape on both sides of the gap between the radiator, oil cooler evaporater and turbo radiator making more air having to come through the evaporater core. It appears to have help quite a bit. I think the vent temp was 54 with sunny 80 degree outside temps.
jenkinsph
Super Star Member
I would think Marble Falls has temperatures over 95 F on many summer days, so let us know how it works for you. I am in New Mexico and will definately check my new tractor HVAC before picking it up.
Steve
Steve
OP
Silver_Knight
Silver Member
Unfortunaltly, about everyday from May thru September!
