[trakman]

Got my 2188 out of my friends shop today. As a last minute request, I asked them to check the A/C pressure and see if I was low on freon. They said the freon level checked ok. I needed to leave with it and on the way home, I'm still not getting a "sharp" cold temp of air out of the vents. just cool air. I know the evaporator is clean, the condensor is clean and the air return behind the seat is not restricted. Any ideas what could be wrong. A guy I was talking to said it might be the expansion valve has failed. What do you guys think?

 

[steigerman]

Could be the evaporator temp sensor or its positioning. I have seen that a few times. Chances are your freind checking the freon level was him testing the prerssures and if they tested good it would indicate that the expansion valve was working properly.

 

[trakman]

Sooooo, where is this "evaporator temp sensor"? You mentioned "it's positioning"....what do you mean, positioning? Thanks

 

[matt]

just went thru mine did the same thing I tried to change ex valve good luck every thing is sooo flemzy @ valve cleaned it as best I could changed drier she cools now!!!

 

[trakman]

A follow up on my A/C problem. Have determined that the compressor only runs for 5 seconds and then the power is killed, probably from the high pressure switch. Do you guys still think it's a plugged or faulty expansion valve? If so is that under the seat by the evaporator?

 

[amax]

there is no way to know what it turning the power of without connecting some gauges.It could be hi pressure or low pressure in the system,you may need to add or remove freon,or clean the condensor.

Maxie

 

[trakman]

OK...if I get a set of gauges, what is the acceptable readings if it full of freon. Have worked on R-12 systems but not at all familiar with the R-134.

 

[amax]

At wot 22 to 35 on lo side and up to 275 to 325 on hi side.

Maxie

 

[steigerman]

Does the a/c presure light come on? If not, it is not a pressure switch issue. Yhe evaporator temp switch tells the computer how cold to keep the evaporator. It is located behind the seat shoved into the evaporator. There is a service builletin describing the proper positioning of it.

 

[matt]

change the ex valve if you can as I said earlier it's under the buddy seat brace wrenches good you don't want to brake core lines change the drier to it's in the same compartment! good luck1

 

[amax]

hi

More than likely you have an overcharge of gas or there is a restriction of air going thru the condenser.

Restricted expansion valve always put low side into vacuum.

Maxie

 

[trakman]

Well whats odd about this is that it only runs for the 3 to 5 second duration. Can't think that airflow over the condensor would cause a high pressure problem in 3 to 5 seconds. Can't tell if the low side will go to vacum because it don't run long enought. An over charge is almost impossible as I've owned the machine for 2 years and have NEVER put any gas in it and the A/C worked good untill about 2 days left of wheat harvest in June.

 

[amax]

Hi
What is the pressure on the gauges without the machine running.
Should be close to ambient temp,may give you an idea of overcharge.
If there is a restricion in a unit that builds that fast would have to be close to the comp.

Maxie

 

[trakman]

Got gauges this morning....high side builds to 425 lbs before the power is cut off. Low side starts to come down but quits when the power shuts off. Must be a MAJOR obstruction, like maybe the expansion valve. If not the expansion valve, where else do I look?

 

[trakman]

If I remember(seen so many readings yesterday)...90 on low side...75 on high side. overcharge is almost impossible, unless a ghost came along and added freon