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Discussion Starter · #1 ·
Question for those of you who run oil coolers on your air seeders, how much hotter do you think the air is heated up using the oil cooler compared to the ambient temperature?
We had some issues this year with urea blocking lines when double shooting and the oil cooler didn't seem to be making a difference to the air temperature. When talking to some other guys they claim they can get up to around 30 degrees above ambient which seems excessive, but they are only estimates, no one actually measured the difference.
Anybody?...
 

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I'd say if your heating the air 30 degrees you better have your system looked at. Two reasons, one your tractor has an oil cooler so it should be maintaining oil temp under a 150F so you don't have enough heat in the oil to raise ambient that much, two to raise the oil temperature the required amount would make the hydraulic system so inefficient it wouldn't be worth it. Think about it, if the oil cooler caused that much rise in air temperature they couldn't put it in front of the engine radiator.
 

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Discussion Starter · #6 ·
Agree with everything that has been said. As I mentioned, these were claims by the other guys not actual measurements.
Is there anyone that runs one of these systems that has measured the difference? I'd just like to know if the ones we have are working correctly. I checked and the difference seemed to be 4-6 degrees above ambient. I can't see it getting any warmer.
Anyone with an Aussie built machine fitted with a cooler have any info?
 

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I have had issues blocking lines in rain so I just cut apart an enviro drum and made it into a shroud for the intake and no more problem. I am not putting urea down though. I agree that the volume of air would be too excessive for an oil cooler to make a difference. I have seen gas burners though; possible they would make a difference. I do find though that getting rid of double shoot or at least blending seed into your ferterlizer makes a difference in the way the system self cleanes.
 

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I never did a temp reading at the boot but while playing around with our horwood bagshaw I was getting a 10c drop in hydraulic oil temp while using the cooler (70c to low 60c) sure you won't have to worry about melting your drop tubes but it couldn't hurt.

During some early testing I did record a 5m/s airflow drop at the upright due to the airflow restriction to the fan inlet. This was corrected by simply blocking the cooler door open 2-3 cm relieving the vacume allowing the thing to breath better while still drawing a large portion of air through the cooler.
 

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I got the sheet metal shop to make me a addaptor for our fert fan, if we start to have issues a length of 8" house hold duct to the artic joint. Helps a lot drawing warm air of the transmission, can fell difference in temp from seed runs to fert runs.
 

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Offroad NT The tractor oil temp may be only 50 C, but because the heat exchanger is plumbed directly after the fan motor, the oil is much hotter there. This way it works most efficiently, but of course you are correct - increases of 30C are a overstimates.

Your just kicking your own ass. Unless the heated air is making it right to the opener it's going to condensate on the way there.

Then with the other foot any restriction to intake flow to the fan will be equally damaging.
And you make this judgement based on how many years of operating one? In my experience, the warmer air does make it to the boot, which can only improve things and not make it worse. I was seeding in drizzling rain last week, and while the rest of the machine was wet, the black primary hoses were dry. When I was stopped you could actually see the steam rising as the rain was evaporating from the hoses. This shows that you are correctly assuming that the air cools as it goes down the hoses, but you are incorrect to assume that heated air doesn't make it all the way to the opener. It does, and while I haven't measured it there, you can feel it.

Secondly, any intake restriction would be minor in a well designed system, and can be compensated for with more fan RPM. It only becomes a blocking issue if you allow trash to build up on the intake of the heat exchanger. There are a lot of happy farmers around here "kicking their own ass", as they seed in the rain without issues.

I have run this machine for the past 3 years an can't attribute any blocks to intake restrictions. Plenty due to other causes, but none due to intake restrictions. Boots don't block with fertilizer (but I do get plenty of blocks from trash wrapping around tynes and physically blocking airflow). All this while using 32:10 fert, which is half urea by weight.

I did take some measurements. In cold conditions last year Oil temp = 37 C. Didn't record fan speed, but this may have been lower, thus creating bigger differences.
Ambient temp - 11.8 C
RH - 82%

Measured at top of a primary head
Temp - 20.7 C = 8.9 C increase
RH - 55% = 27% decrease

Measured this year in the paddock when it was pretty dry. Oil temp 52 C, fan 4250 RPM
Ambient temp - 22.5C
RH - 39.8 %

At top of primary head
Temp = 28.8 = 6.3 C increase
RH = 29.1 = 10.7 % reduction

Measured last week in drizzling rain, that had been going on for hours. I can't understand why RH wasn't higher? Thought it should have been near 100%?
Oil temp 46 C, fan 4350 RPM
Ambient temp 21.5
RH = 64.3 %

At top of primary head
Temp = 24.0 C = 2.5 C increase
RH = 53.0 % = 11% reduction

The lower heat increase in the last test I can only attribute to heat loss from the hoses drying the rain off their outsides.

YMMV!

Heat exchanger measures 500mm x 460mm x 40mm deep, and has 9 x 19mm main tubes. Measured with a Lechler Pocket Wind IV.
 

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Offroad NT The tractor oil temp may be only 50 C, but because the heat exchanger is plumbed directly after the fan motor, the oil is much hotter there. This way it works most efficiently, but of course you are correct - increases of 30C are a overstimates.



And you make this judgement based on how many years of operating one? In my experience, the warmer air does make it to the boot, which can only improve things and not make it worse. I was seeding in drizzling rain last week, and while the rest of the machine was wet, the black primary hoses were dry. When I was stopped you could actually see the steam rising as the rain was evaporating from the hoses. This shows that you are correctly assuming that the air cools as it goes down the hoses, but you are incorrect to assume that heated air doesn't make it all the way to the opener. It does, and while I haven't measured it there, you can feel it.

Secondly, any intake restriction would be minor in a well designed system, and can be compensated for with more fan RPM. It only becomes a blocking issue if you allow trash to build up on the intake of the heat exchanger. There are a lot of happy farmers around here "kicking their own ass", as they seed in the rain without issues.

I have run this machine for the past 3 years an can't attribute any blocks to intake restrictions. Plenty due to other causes, but none due to intake restrictions. Boots don't block with fertilizer (but I do get plenty of blocks from trash wrapping around tynes and physically blocking airflow). All this while using 32:10 fert, which is half urea by weight.

I did take some measurements. In cold conditions last year Oil temp = 37 C. Didn't record fan speed, but this may have been lower, thus creating bigger differences.
Ambient temp - 11.8 C
RH - 82%

Measured at top of a primary head
Temp - 20.7 C = 8.9 C increase
RH - 55% = 27% decrease

Measured this year in the paddock when it was pretty dry. Oil temp 52 C, fan 4250 RPM
Ambient temp - 22.5C
RH - 39.8 %

At top of primary head
Temp = 28.8 = 6.3 C increase
RH = 29.1 = 10.7 % reduction

Measured last week in drizzling rain, that had been going on for hours. I can't understand why RH wasn't higher? Thought it should have been near 100%?
Oil temp 46 C, fan 4350 RPM
Ambient temp 21.5
RH = 64.3 %

At top of primary head
Temp = 24.0 C = 2.5 C increase
RH = 53.0 % = 11% reduction

The lower heat increase in the last test I can only attribute to heat loss from the hoses drying the rain off their outsides.

YMMV!

Heat exchanger measures 500mm x 460mm x 40mm deep, and has 9 x 19mm main tubes. Measured with a Lechler Pocket Wind IV.



25 years of absolutely zero need for such a contraption. Have seeded in the drizzle many times on light enough land. Finished seeding this year in poring rain and did have a couple plug but it was down at the bottom of the opener where the round hose goes into a square receiver and this let water into it.

Glad it works for you though. Here it would be like mounting spinner's on all the wheels kind of useful.
 

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the oil cooler on the tractor does reject heat from the hydraulic fluid, but if you plumb the cooler into the fan circuit on the return side , the heat from the work being done by the fan drive will be exchanged before the oil returns to the main system, thus the heat is intercepted and cooler oil will return to the main system. regardless of what thermostat is in the tractor circuit heat is generated by doing work and the heat is generated by the pump and the pressure it creates after the tractor cooler. the tractor cooler is on the return side of the circuit and if you cool the used oil by interception in the fan circuit you are returning partially cooled oil to the main cooler. measuring the oil temp at the fan return side of the plumbing, not on the main oil return to the tractor cooler will give you a totally different set of temps to calculate heat exchange from. not saying any of the results that others have input are not valid, but the data and results need to be apples to apples, and the math and understanding of what is taking place realistic. running cooler oil back to the main system can only be beneficial, obviously too cool can be a concern in cold climates, but generally if it is that cold the ground is frozen and difficult to seed anyways. i always ran the air system fans for several minutes at least on startup before going to work to stabilize and get rid of any condensation that may have collected overnight, as well as to warm the oil so as not to create hydraulic pressure spikes and exceed the relief valve setting. some designs of hydraulics have multiple relief valves that can and do cause surging of the fan if they are set too close to each other, i am sure others can attest to this experience. using the heat from the oil to heat the air worked for me, but i am not in a high humidity environment, and i was using the auxiliary cooler to keep the heat away from the main cooling system of the tractor, thus benefitting the overall performance of the engine and hydraulic system. less heat to reject= more power to be used..
 

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25 years of absolutely zero need for such a contraption. Have seeded in the drizzle many times on light enough land. Finished seeding this year in poring rain and did have a couple plug but it was down at the bottom of the opener where the round hose goes into a square receiver and this let water into it.

Glad it works for you though. Here it would be like mounting spinner's on all the wheels kind of useful.
Must be a Aussie thing, I see a need for one on the fert side of our bourgult. I fell the same about swathes and pick up fronts what's the point?
 

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25 years of absolutely zero need for such a contraption. Have seeded in the drizzle many times on light enough land. Finished seeding this year in poring rain and did have a couple plug but it was down at the bottom of the opener where the round hose goes into a square receiver and this let water into it.

Glad it works for you though. Here it would be like mounting spinner's on all the wheels kind of useful.
So zero experience operating the system this thread is discussing? Nothing personal, but that hardly qualifies you to make an informed judgement on how well it works.

However, I can appreciate that you don't need it on your rig in your conditions, and I fully understand and respect that opinion. I got by without one on my previous airseeder for 24 years, but had to be pretty cautious about working in rain. It was a completely different beast, and used to glue up the heads and the convoluted secondary hoses, even with DAP. Not much fun chiseling your heads out with a screwdriver when you should be seeding :D

With the new machine I can sow Urea blends through showers with a lot more confidence, but still stop out of habit if a heavier shower comes through. I am 100% convinced that the air heater makes a difference, so I've never operated the new machine without it, but I do feel that it's design would allow it to be less prone to blocks than the old one.

JT mine is a simplicity, similar to Nobby's picture. Oil coolers are standard features on all models. The previous owner had two fans, and two coolers, but removed one fan before I bought it.

 

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So zero experience operating the system this thread is discussing? Nothing personal, but that hardly qualifies you to make an informed judgement on how well it works.

However, I can appreciate that you don't need it on your rig in your conditions, and I fully understand and respect that opinion. I got by without one on my previous airseeder for 24 years, but had to be pretty cautious about working in rain. It was a completely different beast, and used to glue up the heads and the convoluted secondary hoses, even with DAP. Not much fun chiseling your heads out with a screwdriver when you should be seeding :D

With the new machine I can sow Urea blends through showers with a lot more confidence, but still stop out of habit if a heavier shower comes through. I am 100% convinced that the air heater makes a difference, so I've never operated the new machine without it, but I do feel that it's design would allow it to be less prone to blocks than the old one.

JT mine is a simplicity, similar to Nobby's picture. Oil coolers are standard features on all models. The previous owner had two fans, and two coolers, but removed one fan before I bought it.

Don't want to part with the spare oil cooler?
 

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Urea blocking the fert tubes has been causing us big problems for a few years now. We have an Ausplow aircart which already runs a heat exchanger but still have issues. We never really seed in rain or drizzle, but have to run the machine around the clock to get everything in on time and I think the high moisture in fog when it comes in at night is where we start having troubles. Not sure how to fix the problem as yet. Was thinking a gas burner might help but it might take a bit to engineer so I'd be interested in seeing someone's set-up if it's already been done.
Running a larger or second heat exchanger isn't going to help in our case. I haven't measured the oil temp coming off the fan motor but it's luke warm to touch on cold nights.
 
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