Category: A/C Performance Test

Why is my car a/c not cooling ?

This is a list of the most common car a/c failures that lead to a no cooling ac condition in any vehicle:

  • A/C Refrigerant leaks
  • A/C Refrigerant contamination
  • A/C Refrigerant overcharge condition
  • A/C system non-condensable gases contamination
  • A/C refrigerant oil ,overcharge condition
  • Weak A/C Compressor
  • Faulty valve, on electronically controlled variable displacement a/c compressor  
  • Faulty A/C Compressor Clutch Relay
  • Faulty A/C Compressor clutch coil
  • Inoperative A/C Compressor
  • Engine cooling system affecting A/C operation
  • Leaking Heater valve
  • Externally restricted A/C Condenser
  • Internally restricted A/C Condenser
  • Externally restricted engine cooling radiator
  • Faulty Outside Ambient  Temperature sensor
  • Faulty Pressure sensor/switch
  • Faulty Evaporator Temperature Sensor
  • Faulty electric wiring
  • Open fuses
  • Restricted A/C Cabin-filter
  • Restricted evaporator coil
  • A/C Door Actuator malfunction
  • A/C Temperature Door Actuator stuck in the heat position
  • Faulty Expansion Valve
  • Faulty Fixed Orifice Tube
  • Bad drive belt tensioner
  • Worn down a/c compressor drive belt

Why is my car AC running but not cooling?

Newer automotive air conditioner systems have the a/c compressor always operating. The a/c compressor pulley is constantly rotating but the a/c compressor output is controlled in many cases by the ECM or the PCM in the vehicle. The Powertrain control module (PCM) or Electronic controlled Module (ECM) will receive input from different sensors in the vehicle and will command a/c compressor output accordingly.

Do you need assistance with a poor a/c cooling performance ?

Call Today to set an appointment for a complete air conditioner system checkup in your vehicle. Early preventive service could save you a lot of money.

ac temperature out of the vents

How the a/c should be operating in order to cool down the interior of your car

Check inside the vehicle:

  • The A/C climate control should be set to Max Cold Position.
  • A/C Climate control set button On.
  • Recirculation/fresh air mode set to recirculate.
  • Engine temperature should be in the normal range (not overheating)
  • Outside ambient temperature should be sensing outside actual ambient temperature.(Ambient temperature should be above 37 F )
  • Engine RPM’s should in the normal everyday range.
  • With the A/C  blower on Max, the mass of air coming out from the vents should be strong.
  • Cabin air Filter should be clean.
  • A/C evaporator coil should be free from debris and leaks.

Check the engine compartment :

  • The front of the vehicle should be free from any road debris.
  • The radiator and A/C condenser should be free from leaves, bugs or dirt.
  • With the A/C system ON the radiator/condenser fan assembly should be operating.
  • The Drive belt should be running all the accessories and in good condition.
  • The A/C compressor CLUTCH should be engaged with A/C ON.
  • The A/C compressor ECV should be modulating the hvac compressor output for max cold.
  • All A/C lines and hoses should be free from dye, oil ,ice or damage.
  • The A/C system should be properly charged with exact amount of refrigerant specified by the manufacturer.
  • Hvac box drain tube should be draining water from underneath the vehicle.

DO YOU NEED ASSISTANCE WITH THE A/C CHECK UP IN YOUR VEHICLE ?

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what could cause high ac compressor ratio

A high compression ratio can be caused by:

Overcharged A/C system.

Inefficient condenser.

Improper oil balance

A/C condenser insufficient air flow.

Dirty evaporator core.

NEED ASSISTANCE ?!

Auto A/C Repair service and repair near me.AC compressor test.

We have auto ac repair mechanics near you in Miami-Dade County. Call Us today ! 

We use the best OEM and Aftermarket parts available.

ac compressor oil

Auto A/C compressor, compression Test.

To check the auto a/c compressor compression ratio, note on paper the low and high side gauge readings and add atmospheric pressure to both readings. Divide the high side reading (with the atmospheric pressure added) by the low side reading (with the atmospheric pressure added).The result should be between 6.5:1 and 7.5:1. A compression ratio of 8:1 or higher may cause compressor failure. Learn More…

The A/C compressor is considered the heart of the refrigeration system. Compression ratio is the technical expression for pressure difference. Compression ratios are used to compare pumping conditions for a compressor and is an efficient way to evaluate the health of an air conditioning compressor.

If the A/C system operating pressures of your car gives you out of range values CALL US! We come to your place in Miami-Dade. Consider Auto A/C Repair LLC, always near your location!

ac temperature out of the vents

How cold should my AC be at the vent in my car?

The A/C system is designed to provide the passenger compartment with low temperature and low humidity air. During periods of high heat and humidity, an A/C system will be more effective in the Recirculation mode (MAX-A/C).

How cold should my AC be at the vent in my car?

A performance test is the best way to determine whether the system is performing up to design standards. This test also provides valuable clues as to the possible cause of trouble with the A/C system.

How do I check the temperature of my car AC?

Operate the heating-A/C system under the following conditions:

1-Engine at 1,000 rpm at operating temperature

Door and windows closed

2-Transmission in PARK or NEUTRAL with parking brake set (depending on transmission application)

3-A/C-heater controls set to recirculation mode (MAX A/C), full cool, panel mode, high blower and with A/C compressor engaged.

4-Insert a thermometer in the driver side center panel air outlet and operate the A/C system until the thermometer temperature stabilizes.

5-Compare the air temperature at the center panel outlet and the A/C compressor discharge pressure (high side) to the A/C Performance Temperature and Pressure chart.

2016  RAM TRUCK 1500 5.7 L

A/C PERFORMANCE TEMPERATURE AND PRESSURE
Ambient Air Temperature (Apparent)21°C (70°F)27°C (80°F)32°C (90°F)38°C (100°F)
Air Temperature at Center Panel Vent7°C (45°F)7°C (45°F)13°C (55°F)13°C (55°F)
Compressor Inlet Pressure (20 to 30 psi)(25 to 35 psi)(30 to 40 psi)(35 to 45 psi)
Compressor Discharge Pressure(150 to 250 psi)(200 to 300 psi)(250 to 350 psi)(290 to 390 psi)
DODGE RAM CLIMATE CONTROL
ac temperature out of the vents

How do I check the temperature of my car AC?

How do I check the temperature of my car AC?

 SYSTEM PERFORMANCE TEST

How do I check the temperature of my  2015 Mazda 6 AC?

1. Measure the air conditioner output temperature after approx.10 min have elapsed from engine start.

2. Place a dry-bulb thermometer in the driver-side center Vent outlet.

  1. Start the engine and warm it up.4. Set the fan speed to MAX HI.5. Turn the A/C switch on.

    6. Set to RECIRCULATE mode.

    7. Set the temperature control to MAX COLD.

    8. Set to VENT mode.

    9. Close all the doors and windows.

    10. Maintain the engine speed at 1,500 rpm.

    11. Wait until the air conditioner output temperature stabilizes.

    Stabilized condition
    – The A/C compressor repeatedly turns on and off at regular intervals.

    12. After the blower air is stabilized, read the dry-bulb thermometer.

    13. Verify the ambient temperature.

    14. Verify that the temperature reading is in the shaded zone.

AMBIENT TEMPERATURE CENTER VENT TEMPERATURE

41 F

39.5 F

50 F

4.5 F

59 F

41 F

68 F

42 F

77 F

43 F

86 F

43.5 F

95 F

47 F

104

50 F

We could easily know what should the a/c temperature be at the vents be checking this manufacturer chart. If the A/C system in the car is working properly the temperature should be near these values.

How cold should my AC be at the vent in my car?

How cold should my AC be at the vent in my car?

How cold should my AC be at the vent in my car?

The do a performance test and know how cold should the the a/c be at the vent in your car, you should follow the manufacturer specifications. The ambient air temperature must be at least 16°C (60°F) .

Do not induce additional air flow across the front of the vehicle during the test.

 

What temperature should the A/C blow ? 

The A/C system is designed to provide the passenger compartment with low temperature and low humidity air. During periods of high heat and humidity, an A/C system will be more effective in the Recirculation mode (MAX-A/C).

We could easily know what should the A/C temperature be at the vents be checking this manufacturer chart. Taking into account  50-60 % relative humidity and an ambient air temperature of 77 F,86 F,95 F ,the discharge air temperature at the center vent should be in the range of :

50-54 F

56-60 F

63-70 F

if the A/C system in the car is working properly.

How cold should my AC be at the vent in my car?

A performance test is the best way to determine whether the system is performing up to design standards. This test also provides valuable clues as to the possible cause of trouble with the A/C system.

How do I check the temperature of my car AC?

Testing must be performed as follows:

Vehicle location Indoors or in the shade (in a well-ventilated place)
Doors Closed
Door Windows Open
Hood Open
TEMP. Max. COLD
Mode switch Front (ventilation) set
Recirculation switch Set (in-cabin recirculation ) set
Blower Max. speed test
Engine speed Idle speed
Operate the air conditioning system for 10 minutes before taking measurements

 

 

TEST READING

Recirculating-to-discharge Air Temperature Table

Inside air(Recirculation air) at blower assembly inlet  

Discharge air temperature at center vent

F

Relative humidity

%

Air temperature

F

 

50-60

77 F

  50-54

86 F

56-60

95 F

63-70

60-70

77 F

54-59

86 F

60-67

95 F

70-76

***This values are for NISSAN-DATSUN Maxima V6 3.5L***

 

What causes an ac compressor to lock up

What causes an ac compressor to lock up

Inaccurate refrigerant(freon) charges increase the chances of auto ac compressor lock up. Modern auto a/c systems require super accurate charging. Being off as little as 2 ounces can cause problems.R-134a and R-1234yf ac system tolerances require charge rates that must remain or should be charged within +/- 5% of OEM recommendation. SAE J2788 requires charge accuracy of +/- one-half ounce.

Attempting to charge by cans is History !!

Car ac compressor lock up due to improper compressor lubrication.

Refrigerant moves the oil inside the ac system and helps to cool down the ac compressor. An undercharge or overcharge refrigerant condition will increase the air conditioning compressor temperature and a change in oil viscosity and lubrication characteristics. Most compressor lock ups are the result of a lubrication problem.

AC compressors lock up due to ac system contamination

Auto ac compressor damage may occur because of system contamination. Anything more than the correct type of freon and oil is a contaminant. The use of sealers to fix small refrigerant leaks will cause oil and refrigerant contamination and ultimately ac compressor lock up. Sealer can’t be removed from the A/C systems. The contaminated components must be replaced.

The use of excessive Dye to help finding leaks in the ac system could create a contamination problem as well, increasing the normal working pressure of the ac compressor and the overall efficiency of the air conditioning system.

Improperly replacing any component in the automotive air conditioning system where the system must be opened for replacement of the damaged part and not evacuating the system before recharging it with the proper amount and type of refrigerant will contaminate the ac system with air. Air and moisture inside the system will create excessively high operating pressures and temperatures and eventually could lead to a compressor lock up.

Inefficient ac condensers and air conditioning compressor lock up

Debris on the condenser will affect the desuperheat, condensation and subcooling processes happening in the auto ac condenser.AC condenser with bent or missing fins will be unable to efficiently operate. An inefficient ac condenser will cause an auto ac compressor to lock up.

Low Refrigerant charge and electronically controlled compressor lock up ?

The car engines in vehicles with the clutchless compressors should not be run without refrigerant in the A/C system. Without refrigerant to move the oil, the auto ac compressor may not be properly lubricated and compressor lock up may result.

Do you need assistance inspecting the state of your ac compressor in your vehicle?

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evaporator core replacement

Air flow restriction.

When the fins and air passages of an evaporator are clogged with dirt, air will have a difficult time passing through the evaporator. Since the principles of air conditioning require the heated air around the evaporator to lose heat, a vehicle with a clogged evaporator will have poor A/C performance.

Evaporator core maintenance.

The evaporator core should be removed from the case to properly clean it. Airborne debris, such as leaves, lint, hair, and other contaminants, enters the evaporator case and clings to the wet evaporator core.

The A/C drainage.

The drain is for the purpose of removing the condensation that forms as a result of humidity being removed from the intake air. It is nearly impossible to adequately clean an evaporator core without first removing it from the case.

Do you need to service the evaporator core in your car ?

Call Today ! We have ASE certified mechanics near you to service and replace the evaporator core in your car.