3000 Series A/C Issues

[sunnyside360]

Talked to the JD dealer this morning about the AC and torn & missing isolators on the 3720. They are picking up the tractor tomorrow morning to check and repair whatever. He said that in general the air vent temperature should be at least 30 deg lower than the outside temp. For example, if 90 deg outside the vent temp should be 60 deg, otherwise something is wrong. He also said they have seen very few problems with the AC on the 3000 series tractors. This is the largest JD dealer in these parts.
Can't complain about the service since they are picking up the tractor tomorrow morning and no mention of pickup/delivery charge.

 

[nmu98]

I would probably fix the seal. 88 is not that hot. I think the some cabs have poor seals in the air box.

That picture makes it unclear where that seal goes. Not knowing where the internal seal sets makes it hard to put it in. That is why i was not concerned about it in the first place. All my other seals are perfect since i re-did them. I cannot see losing much from that internal seal. There is no chance of pulling any outside air in... Probably why JD has not put them on most machines. I would assume it has been phased out like the loadmatch switch.

 

[sunnyside360]

Talked to the JD dealer this morning about the AC and torn & missing isolators on the 3720. They are picking up the tractor tomorrow morning to check and repair whatever. He said that in general the air vent temperature should be at least 30 deg lower than the outside temp. For example, if 90 deg outside the vent temp should be 60 deg, otherwise something is wrong. He also said they have seen very few problems with the AC on the 3000 series tractors. This is the largest JD dealer in these parts.
Can't complain about the service since they are picking up the tractor tomorrow morning and no mention of pickup/delivery charge.

Had to put the top back on since the JD dealer is picking up tomorrow and just for grins I put duct tape over the areas where isolator 10 is torn and cranked up the A/C. Low and behold the vent air temp dropped down to 54 deg F, while cab temp was 64 deg and outside temp was 74 deg. The A/C system dropped air temp 20 deg (74 - 54). I have renewed hope for cool air in the cab. Already cannot wait to get the tractor back from the dealer with all the fixes.

 

[truckie36]

Our 3320 roof seal came damaged from the dealer. They had the roof off to install the radio and other accessories. We fixed it ourselves with self adhesive foam from Lowes. There were other areas in the center that were not damaged but you could not see any indentation in the seals, so we added extra in those spots. We also put some foam in to separate between the fresh air intake and recirculate intake to reduce the fresh air intake. It's much cooler now. The next step is to add an electric pusher fan in front of the radiator to see if that will improve it further.

 

[Nuru]

I would probably fix the seal. 88 is not that hot. I think the some cabs have poor seals in the air box.

Opening the top up a second time revealed additional breakage on the sides. From taking a good long look at the isolators and seals, it seams that, if you have breakage/holes in the isolators over the doors, that would be a good spot for outside air to get mixed with the cooled air and go right into the cab. If the breaks are at the rear or front, it seams that other seals/isolators would help.

 

[Nuru]

Our 3320 roof seal came damaged from the dealer. They had the roof off to install the radio and other accessories. We fixed it ourselves with self adhesive foam from Lowes. There were other areas in the center that were not damaged but you could not see any indentation in the seals, so we added extra in those spots. We also put some foam in to separate between the fresh air intake and recirculate intake to reduce the fresh air intake. It's much cooler now. The next step is to add an electric pusher fan in front of the radiator to see if that will improve it further.

truckie36; that sounds pretty good. I also used window door seal from Home Depot to repair the holes in mine until the new isolator seal shows up. Next time tytou have the top off can you take some pics of the seal imnprovements you installed? I would like to look at doing some of them.

 

[Nuru]

That picture makes it unclear where that seal goes. Not knowing where the internal seal sets makes it hard to put it in. That is why i was not concerned about it in the first place. All my other seals are perfect since i re-did them. I cannot see losing much from that internal seal. There is no chance of pulling any outside air in... Probably why JD has not put them on most machines. I would assume it has been phased out like the loadmatch switch.

I did not seee #11 either and my AC works fine. I am going to request it and install it to see what results I get.

 

[nmu98]

I did not seee #11 either and my AC works fine. I am going to request it and install it to see what results I get.

Please take a picture of where it goes. I have the seal sitting in the shop.... I just don't want to put it in and see decreased results. i am pretty happy

 

[Nuru]

Please take a picture of where it goes. I have the seal sitting in the shop.... I just don't want to put it in and see decreased results. i am pretty happy

Sure, OBTW, my dealer asked me to send them the seals to them for an exchnage. So since it only cost 19 bucks for the 11 and 19 bucks for the 10, I told him to send them and refund me later when JD approves it. The 11 is not visible so they should send that one with charging me first.

 

[Silver_Knight]

Well the saga continues! Went out the other day when the temp was in the 80s and was sweating in my A/C cab. I'm gonna take it back in and have them put a blower on the evaporator.

 

[tglass]

Mine works good, but how do you check the seals without removing the top, and how do you remove it? Is that how you gain access to the radio, ac ducts etc. and how hard of a job would it be if needed?

 

[Nuru]

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

 

[Nuru]

Well the saga continues! Went out the other day when the temp was in the 80s and was sweating in my A/C cab. I'm gonna take it back in and have them put a blower on the evaporator.

Yeah, that sounds like a good plan.

 

[jenkinsph]

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

 

[jenkinsph]

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

 

[Silver_Knight]

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

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]

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

 

[Silver_Knight]

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

Unfortunaltly, about everyday from May thru September!