Case 65A - Cab air conditioning

[DB Pilot]

Before I call my dealer I thought I might just run this question here and maybe someone has experienced this problem with their air conditioner. With summer coming on and air temperatures about 60. Running my 2020 Case 65A utility tractor at idle I'm getting cold air inside that glass cage. As soon as I throttle up to speed about 1500 RPM I lose the cool air. Back to idle and cool air again. I also noticed the radiator for the A/C also feels very warm when raising RPM's.

It has been suggested to me that it might be a sensor for the unit?

I have cleaned the Cab filters and made sure the radiators are dust/debris free.

 

[Tx Jim]

1st thing I'd recommend is installing a maual cutoff valve in a heater hose. If heater coolant control valve is leaking internally allowing hot coolant to cycle through heater core this is a cheap solution. My '91 JD 4255 has had manual valve installed in heater hose for many yrs

 

[5030]

WOG (water-oil-gas) full port ball valves are cheap, any box or hardware store will have them and you only need to shut off one side of the heater line (usually have 2 lines). I have never seen a flow control valve on any heater than didn't leak a bit, even new. Cut the hose in an accessible spot, install the valve and hose clamp it and you are golden. You'll probably need 2 short nipples as well to mate the valve to the hose. Off on the summer, on in the winter. Easy peasy.

 

[5030]

I have to ask, did you bother to clean the in cab evaporator when you cleaned the cabin filters? A dirty evap cab coil will not efficiently transfer cold refrigerant to the air flow. I clean both my evap and heater cores yearly when I clean the cabin filter.

 

[LouNY]

I would wager that you are a bit low on gas in the AC system, speed the compressor up and it pumps faster and
you get a low suction pressure shutdown of the compressor.
Also as has been mentioned cutting off all the heat helps in hot weather.

 

[5030]

I would wager that you are a bit low on gas in the AC system

That could be as well but I'd be adding refrigerant in the form of dry propane instead of R whatever. Propane is a much more efficient medium for heat transfer and is compatible with all refrigerants used today.

 

[DB Pilot]

Thanks for the ideas. I was working with the Tractor this morning and noticed the in cab filter looked a little dirty, so that, and the Cab evaporator, which I have never looked at. Will let you know results.

 

[LouNY]

That could be as well but I'd be adding refrigerant in the form of dry propane instead of R whatever. Propane is a much more efficient medium for heat transfer and is compatible with all refrigerants used today.

Or as it can be labeled R290, I've used my 20 pounders before.

 

[DB Pilot]

I have had success with my air conditioner in the Case 65A. I read the manual and found that it clearly states "Not to wash the cabin filters". So I washed the filters, figuring what difference does it make if I need new filters. I washed off very fine carcinogenic particles with no damage to the filters. I am still not 100% sure but I have been getting cool air at operating speeds. The inside filter could not be washed. But the outside filters seem to be sturdier. The filters did not seem that dirty but again a fine particle powder came off and now I have good air in the cab.

 

[tmc_31]

I have to ask, did you bother to clean the in cab evaporator when you cleaned the cabin filters? A dirty evap cab coil will not efficiently transfer cold refrigerant to the air flow. I clean both my evap and heater cores yearly when I clean the cabin filter.

Wow, it is a major deal to clean the evaporator on my NH TN70D. You have to remove the headliner in the cab, remove the heater core/evaporator/fan enclosure then split the enclosure to get to the evaporator. Just finished cleaning the coils and reinstalling the enclosure. What a pain in the A$$. But the AC is back to work so it was worth it. Last job with it was mowing 35 acres. out door tem 107 deg. Cab was like a solar oven.

Tim