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Where is the low side service port located?

Where is the low side service port located?

The low side service valve is located in the line that runs from the compressor through the evaporator (firewall) and up to the condensor on the low pressure (suction) side of the system.

Where is the high side service port?

Locate the high side port on the line that goes from the compressor to the condenser. The high side port will have a 16 mm quick-disconnect valve fitting with a red cap on vehicles with R134a, or a 3/8-inch threaded valve fitting on vehicles with R12.

What color is the low side of an AC system?

Red hose goes to the high pressure side, blue goes to the low pressure side and yellow hooks to Freon source, can, etc.

Why is my high side pressure low?

Lower than normal pressures on both high and low side, with the correct amount of refrigerant, could mean a problem building pressure in the system or too much heat is being removed at the condenser. A pressure switch or sensor could be bad.

How much freon does a 2002 Lincoln LS hold?


Year Model Refrigerant
2003-2004 All Engines 32.00
1998-2002 All Engines 38.00
1997 All Engines 34.00

Do you add freon to the low or high side?

The freon is added on the LOW PRESSURE SIDE ONLY. The hose tool you bought is made so you can only hook to the low side as the high side and low side fittings are different sizes and shapes for SAFETY’S SAKE.

Do you charge AC system on high or low side?

Every auto air conditioning system has two service ports: one on the high pressure and one on the low pressure side. When recharging with AC Avalanche refrigerant, for safety, you will charge through the low side service port. Never charge through the high side port.

What are the signs of a bad expansion valve?

Symptoms of a bad expansion valve

  • Car AC system isn’t cooling enough or won’t cool at all.
  • High side pressure is high.
  • Air coming from vents is frosty.
  • AC blows cold, then hot.
  • AC kicks on and then immediately kicks off.
  • Airflow drops dramatically from vents.

What should the high and low side pressures be?

The system should be about 25 to 30 psi on the low side and 200 to 250 psi on the high side. If the ambient temperature is higher or lower than normal (70 to 80°F) the pressures will go up or down accordingly.