Mahindra 7010 Air Conditioning Solutions

jamesdaniel · Jul 30, 2015

Have replaced compressor, dryer, and thermal expansion valve, installed 29 oz. Freon 134A. At 1,500 RPMS high pressure runs 165- low pressure runs 18 PSI.
What could be the possible cause of not cooling?

Thank you for your response,
Daniel

TBN Support · Jul 30, 2015

Welcome to the forum. :welcome:

I'm going to move your thread on over to the Mahindra section to see if we can get you some quick answers. This is not the best time of year for an a/c failure!

Texan4Life · Jul 30, 2015

Your undercharged.... did you add new oil for compressor and dryer?

skipmarcy · Jul 30, 2015

Either charge is too light or expansion valve is stuck wide open or if system uses an orfice tube it is too large. Did you pull a good, solid vacuum on the system before recharging ? Need to pull a bare minimum of 27" - 28" vacuum for at least a half hour to an hour. R134a needs to be accurately measured to get best efficiency. Performance goes down quickly if either overcharged or undercharged by just a small percentage, not as forgiving as R12 was. You don't want the low side to get much under 30 psi or it can freeze-up the evaporator on humid days. High side will vary a lot more depending on ambient air temp., humidity and airflow across the condenser. Anywhere from 200 to 350 psi depending on all of the above mentioned.

jamesdaniel · Jul 31, 2015

Texan4Life said:
Your undercharged.... did you add new oil for compressor and dryer?

I checked the oil level in compressor, since I had flushed all lines, I added 3 oz. refrigerant oil.

Texan4Life · Aug 1, 2015

jamesdaniel said:
I checked the oil level in compressor, since I had flushed all lines, I added 3 oz. refrigerant oil.

not sure what you mean by checking the level in the compressor? Since you flushed all lines, that would have flushed out left over oil from all the other components like evaporator, and condenser.... Do you have access to a service manual? it should list oil amount for each component (compressor, dryer, evap, condensor) or at the very least a total system oil amount.

from an empty system 3oz of oil is not enough and can effect system pressures.

If the amounts are unknown, a rule of thumb is 2oz for dryer, 1oz for condenser, 1oz for evaporator. If the condenser and evap. are not removed/replaced it is easier to add their oil amounts to the dryer as it is a safe reservoir so as to not slug the compressor with oil.

You have two option for adding oil, either empty the system and add directly to the dryer or if you do not want to discharge the system you can get oil charge cans from most autoparts stores. they usually have 2oz of oil and 1 oz of r134a to push the oil into the system. when charging with a oil charge it is best to let it in slowly with the can upsidedown so the oil is pushed in.

Keep us in the loop! cold A/C is a must!!