B3000 A/C Re-Charge help

[TimP]

Hi All.

MY A/C isn't getting as cold as it used to and I took a look at the sight glass and saw it started out with a very bubbly stream and then went to clear, as in no fluid as far as I can see.

I have ordered some cans of 134A Freon and a decent set of manifold gauges.

But, once I get it all, not positive the procedure to add a charge to the system.

What are the pressure reading I should be looking for when I add the 134a on my system?

Do I just hook up the quick connects to the Low and High pressure fittings and add the freon until I get the proper pressure?

Thanks for the help.

 

[5030]

Hi All.

MY A/C isn't getting as col das it used to and I took a look at the sight glass and saw it started out with a very bubbly stream and then went to clear, as in no fluid as far as I can see.

I have ordered some cans of 134A Freon and a decent set of manifold gauges.

But, once I get it all, not positive the procedure to add a charge to the system.

What are the pressure reading I should be looking for when I add the 134a on my system?

Do I just hook up the quick connects to the Low and High pressure fittings and add the freon until I get the proper pressure?

Thanks for the help.

Follow the instructions on the gauge kit and 134A can. Far as charging a low system, you need around 150 psi on the high side with the compressor running and the ac on high, full cold. With the compressor energized, you should see a solid whitish stream of 134 in the sight glass.

Be apprised however that usually, poor cooling isn't the freon level but a dirty cab condensor. Have you cleaned it lately. I clean mine yearly. The cab mounted filter works but dirt will still get in and clog the cab condensor. I'd clean the system first and fiddle with the freon second.

 

[5030]

Don't add oil either if you do add refrigerant. The oil in Kubota's PAG 46 will remain in the system whether it's low on refrigerant or not. Resist the temptation to add oil unless you replace a component. The oil will be adhered to all the system components inside them.

Like I said, first clean all the heat exchangers, under the hood and in the cab before fiddling with refrigerant.

I've heard many people say that the Kubota climate control is marginal at best. I disagree. Mine will freeze you out no matter how hot it is outside, even on a 95 degree day, I cannot advance the blower setting past 1. However my HX's are clean and I keep them clean. Finally, if you do add refrigerant, do not add refrigerant with sealer in it, just straight no additive freon 134. The sealant can gum up the works. If you suspect a leak then pull the system down with a vacuum pump and let it stand for an hour with the vacuum on it. If the gauge don't move you should be ok. If it does, it's time to buy a leak detector, charge the system and find the leak and repair it. Most times systems will leak from the Schrader valves (where you inject freon) and check the pressures. If a Schrader valve is leaking, usually a quick release of refrigerant with a small flat blade screwdriver will clear the valve and restore the seal. Wear gloves and eye protection at all times. Refrigerant in your eyes will blind you and contact with bare skin will cause immediate frostbiite. If the system apperas to hold vacuum for an hour but slowly looses the charge, the addition of a fluorescent die will pinpoint the leak as well.

Refrigeration isn't all that complex but overcharging any system can cause serious consequences. You can destroy the compressor or rupture a refrigerant line. Mine does super at 150 on the high side. Yours may or may not. Only way to really tell is a thermometer in a a vent and note the temperature differential between ambient and refrigerated.

 

[5030]

:thumbsup:



What you're probably seeing is a flow of liquid freon when the bubbles disappear, especially if your suction line is getting cold. Low side pressure is usually around 35-40 and high side is closer to 200 psi. If you're getting rapid cycling, then you may be low on freon. Otherwise, clean your condenser and evaporator coils first and check filters.

You really cannot see 134a. It's essentially clear to a milky white color depending on the brand. I've read comments where people say they can see the oil too. That is BS. PAG46 is almost clear. Unless you have X-ray vision you won't see it and the only way to check the oil is with the cotton ball test.

 

[TimP]

THANK YOU ALL for the help, tips and guidance.

Sounds like I need to clean the components and see if it makes a difference. I have had my B3000 for about 1 -1/2 years and have not cleaned the evaporator.

I have no idea if it was ever cleaned in the past.

Unfortunately, I have to remove the roof to get at the evaporator.

Not sure what I need to remove to get the roof off. I'll look at the parts diagram to see if it shows what screws/bolts need to come out.

The cab fresh air filter was replaced last Feb.

If the 134a is clear and I can't really see it, how can I tell if I am low, or just can't see the liquid thru the sight glass?

 

[Snappy BX]

As one had said, if your compressor is cycling rapidly, then you are probably low on Freon. With the system off, your gauge set should read approx. ambient temp, example - 70 degree day, 70 psi on both sides of gauge with system off.
When tractor is started and system on, low side should be 32-40 high side 150-225 depending on temp of day and airflow over condenser.
NEVER, EVER open High side gauge with tractor running and system on especially if you are trying to recharge the system. The pressure in the high side will exceed the pressure in the can possibly causing injury or death.. Finally if you system is low you have a leak, find the wet spot. That's where the oil in the system has left a wet spot and the dirt adheres to it.
If the system does have a leak, it should be repaired, evacuated (with a vacuum pump) and recharged with the correct amount of Freon.
Sorry for the long winded answer, hope it helps and good luck.

 

[RickB]

We should be using the correct terminology to avoid confusion. The condenser coil is in front of the engine fan, the evaporator coil is stacked with the heater coil in the cab roof.

 

[RickB]

As one had said, if your compressor is cycling rapidly, then you are probably low on Freon. With the system off, your gauge set should read approx. ambient temp, example - 70 degree day, 70 psi on both sides of gauge with system off.
When tractor is started and system on, low side should be 32-40 high side 150-225 depending on temp of day and airflow over condenser.
NEVER, EVER open High side gauge with tractor running and system on especially if you are trying to recharge the system. The pressure in the high side will exceed the pressure in the can possibly causing injury or death.. Finally if you system is low you have a leak, find the wet spot. That's where the oil in the system has left a wet spot and the dirt adheres to it.
If the system does have a leak, it should be repaired, evacuated (with a vacuum pump) and recharged with the correct amount of Freon.
Sorry for the long winded answer, hope it helps and good luck.

Good advise.

 

[5030]

We should be using the correct terminology to avoid confusion. The condenser coil is in front of the engine fan, the evaporator coil is stacked with the heater coil in the cab roof.

Thank you Rick. One is in front and the other is buried.....

 

[TimP]

We should be using the correct terminology to avoid confusion. The condenser coil is in front of the engine fan, the evaporator coil is stacked with the heater coil in the cab roof.

Thanks... I'll correct my previous post. I always get them confused.... :.(