dk55 ac questions

[trac]

I have done some work on the DK55 air conditioning in the past and I can offer you a little help. Had a 55 freezing up a few years ago and had gone through all the cleaning processes in the cab with same results. There were no air bubbles in the receiver dryer sight glass, so I discharged the system. I removed the receiver dryer and found rusty contamination inside of the connecting lines. It life span had been used up, so I replaced it. Upon talking to a factory rep., he advised to replace the expansion valve also because the contamination could of partial plugged it. I added a few oz. of lube oil to the compressor, evact the system and charged with the proper amount of freon. The customer said the air was running alot colder, then when he had purchased the tractor from me new. Hope this helps, trac

 

[8404]

Ok so ive switched relays around and found no change, in that both relays still function. so ill try the uncharge and recharge system next and ill look into those parts "Trac" is talkiing about this sight windo is on top of the dryer right so that is were the bubbles will appear? any way the tractor is 7 years old and might not have an electrical problem just old freeon that needs changed.
is the expansion valve located after the dryer in this picture part number 2

 

[8404]

http://www.paigetractorsparts.com/p...-00121_-_)/01-09|~DK55C-M-CABIN/0109DK55C0023

 

[slc10844]

The expansion valve is normally between the dryer and the evaporator. That should be #2-valve B. I'm not sure what #1-valve A is. Perhaps TRAC can shed some light on what both valves are. Replace the receiver/drier if you are going to open the system. The old freon should be recaptured into a recycling machine and the prescribed amount installed. You will also need to add refrigerant oil specific to your system. Each componet holds a certain amount of oil that needs to be replenished and the manufacturer will usually list the amount in the service manual. It is important to evacuate the system before recharging to remove any moisture. I would expect to see some bubbles in the sight glass, even on a fully charge system. If you do not see any bubbles it may be overcharged and cooling will be diminished.

 

[8404]

i wont try this job myself. i dont have the tools or the experiance to do it but ill have the new parts ready for who ever i hire to do it.

 

[Coyote machine]

Looks like the switch wires are NOT connected to the switch screwed into canister with the rusted threads in one of your pictures. If that item is your receiver/dryer I would replace it. One of the other pics shows the amount of compressor oil necessary to be added on a recharge, and the type of oil to use. You need to have all the new parts ready for use before opening the system lines to reduce excess moisture from entering into the lines. Once opened after draining out the old freon for recycling the new parts can be installed. Find out if you should be using pipe dope or teflon tape on the threaded items like expansion valve and receiver dryer- a competent ac/tech will know what is being used these days.
Once a vacuum is drawn and it holds for the required time to verify no leaks in the system then it is time to add freon and oil to the system.
Then you can check temperature at your cab vents with a thermometer, and flow of freon at the evaporator/canister sight glass. Note max temp and ambient temp for future reference so you will know when the system is not producing.
One other thing you may be experiencing is a bad compressor clutch if the relays and switches are all working correctly. I'd call Paige tractor and have them determine which parts you need for your system instead of guessing which parts to buy- that could be costly if you get incorrect non-returnable ones.

 

[slc10844]

Find out if you should be using pipe dope or teflon tape on the threaded items like expansion valve and receiver dryer- a competent ac/tech will know what is being used these days.

Thread sealant is not necessary. Lines and fittings use o-rings and should be replaced.

 

[8404]

sic10844, thats why i made pictures i would have never noticed that sticker telling what type and how much oil to use thanks for pointing that out. I disconected the wire on the dryer to take the picture.

 

[Coyote machine]

sic10844, thats why i made pictures i would have never noticed that sticker telling what type and how much oil to use thanks for pointing that out. I disconected the wire on the dryer to take the picture.

You're welcome!

 

[trac]

On this type of system of a tractor, the manufacture is more concerned about high pressure. The switch on the dryer is set to shut off the compressor at a certain pressure well below blowing out the sight glass . I have seen this happen so, never bypass this switch. Pressures can run 100psi + outside ambient temps. It's best to hire an expert to do this work so, it is done correctly. As previously stated, you will need a receiver dryer, orings. I like to use 134A with the dye in it on older tractors, so leaks can be spotted in the future.

 

[8404]

ok, so i guess changing out the receiver drier and o-rings is nomal procedure anytime you replace the freon.

 

[Coyote machine]

ok, so i guess changing out the receiver drier and o-rings is nomal procedure anytime you replace the freon.

Anytime you open the lines to replace parts the receiver dryer should be replaced. Moisture in the lines is unacceptable, and it is the R/D's 'yob to remove it to an acceptable level. The system's yob is to compress freon gas and then extract heat and change phase into liquid, then the whole cycle again and again 'till the end of time.

 

[8404]

Update, Im so stuppid, I finally propperly cleaned the AC condencer thats in front of the engine radiator, it looked clean at first glance but after i removed the screens and could see between the two i found it was clogged full of dirt. anyway I mowed for 4 hours today in 100`temps and stayed cool. and to think all these days of swetting when all i needed was a water hose. anyway thanks for all your help, and some of you even told me axactly what the problem was and i just didnt see it, to be honest i confused the transmission cooler for the AC condensor for a few days of looking things over.

 

[trac]

Glad you got the system working with just a little cleaning. Clogged condenser raises the high side pressure, resulting in the high temp switch shutting the compressor down. Once the pressure lowers, the compressor comes on, and will just keep cycling until the problem is repaired. Dirt, heat and high pressure is an air conditioners worst enemy. Keep those condensers clean. We are approching 100 degrees with dewpoint above 70. Air techs. are very busy. Has been many years since we have had this type of weather. I like it 85 or so. trac