# How does refrigerator pressure on a/c system - 2005 Nissan Pathfinder

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• Nissan Master

Engine at idle; low side 25 -35psi, high side 150 -200psi
at 2000 rpm; low side 15 -25psi, high side 175 - 250psi

Posted on Jan 01, 2014

Hi,
a 6ya expert can help you resolve that issue over the phone in a minute or two.
best thing about this new service is that you are never placed on hold and get to talk to real repairmen in the US.
the service is completely free and covers almost anything you can think of (from cars to computers, handyman, and even drones).
goodluck!

Posted on Jan 02, 2017

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## Related Questions:

### Were is expansion valve in a 2002 Chevy trailblazer in the truck

Are your asking about TXV valve thermal expansion valve for A/C system ? If you are ,yours doesn't have one . Has an orifice tube , The orifice tube is located in the liquid line between the condenser and the evaporator !
The orifice tube is the dividing point for the high and the low pressure sides of the A/C system. As the refrigerant passes through the orifice tube, the pressure on the refrigerant is lowered. Due to the pressure differential on the liquid refrigerant, the refrigerant will begin to vaporize at the orifice tube. The orifice tube also meters the amount of liquid refrigerant that can flow into the evaporator.
Unless you are referring to the auxiliary A/C system for the back of the vehicle , it uses a
The rear TXV is located at the rear evaporator inlet. The TXV is the dividing point for the high and the low pressure sides of the rear A/C system. As the refrigerant passes through the TXV, the pressure on the refrigerant is lowered. Due to the pressure differential on the liquid refrigerant, the refrigerant will begin to boil at the expansion device. The TXV also meters the amount of liquid refrigerant that can flow into the evaporator.

May 23, 2015 | 2002 Chevrolet TrailBlazer

### My car didn't take the R-134a

If your car ac is not taking in refrigerant, it could be caused by several things.
If you have recently done work on the system and you are going to fill the system the first time, you will need to pull a very deep vacuum before trying to charge in refrigerant. If you have already properly evacuated the system and having problems getting the correct charge adjusted, you may be having problem with pressure equilizing between the refrigerant source and your ac system. To get the refrigerant going again, you need to connect the charging hose on the low pressure side of the ac system and turn the fan and ac on cool. The pressure in the ac system on the low pressure side will get lower than the pressure in the refrigerant container and flow will start. When charging initially, charge liquid on the high pressure side and with the ac system running, charge gas on the low pressure side. To charge liquid, invert most container so spout is down, to charge gas, keep container right side up. Charging by gas help you to not over charge your system. Beware on most vehicle ac systems the suction and discharge connections are two different sizes and require the proper adapter. If you still having problems creating a pressure difference to move refrigerant, you can try immersing the refrigerant container in warm water or applying warm air to the exterior of the container.
Hope this helps.

Jan 02, 2015 | Cars & Trucks

### 2007 ford KA blowing hot air

see this causes and fix it. God bless you
Compressor Checks
Start with the compressor. Does it engage when you turn on the A/C?
If so, the compressor is working and the A/C system probably contains enough refrigerant to make cold air, so the problem is inside the HVAC unit. Replace the motor that controls the blend air door (this is a difficult job and best left to a professional since it involves tearing apart the HVAC unit -- about an 8 to 10 hour job!).
If the compressor does not engage when you turn on the A/C, see if it will run by jumping the compressor clutch wire directly to the battery (use a fused jumper wire). If the compressor works when you jump it, and the A/C blows cold air, the system contains refrigerant and the fault is likely a bad A/C compressor clutch relay or a bad clutch cycling switch or pressure switch.
If the compressor does not engage when you jump it, the problem is a bad compressor clutch.
If the clutch engages but the compressor does not turn (the belt will start to slip and squeal), the compressor is locked up and you need a new compressor.
If the compressor clutch engages and turns the compressor, but the A/C still does not blow cold air, the system is probably low on refrigerant and needs to be recharged.
Refrigerant Checks
Connect an A/C pressure gauge to the HIGH SIDE service port (located in the high pressure hose that runs between the compressor and the condenser in the front of the engine compartment). The gauge will tell you if there is any pressure in the system. Simply depressing the service fitting valve with a small screwdriver to see if any refrigerant squirts out is NOT an accurate check because it tell you how much pressure is in the system. It may still have some pressure but not enough to trip the low pressure safety switch so the compressor will engage.
If your A/C system is low or out of refrigerant, check for leaks, then have the A/C system vacuum purged to remove air. After the air is out, it can be recharged with the specified amount of refrigerant. It is important to get any air out as this will reduce cooling efficiency and may make the compressor noisy.
A/C System Functional Checks
If the refrigeration circuit seems to be working (refrigerant in the system, compressor running and building pressure), but there is still no cooling, the problem might be an obstruction in the orifice tube (located in the high pressure hose between the condenser in the front of the radiator, and the evaporator located in the passenger compartment). A blockage here will prevent the refrigerant from entering the evaporator or recirculating through the refrigeration circuit.
If the orifice tube is plugged, the high side pressure reading will be lower than normal, and the low side reading will also be lower than normal because no refrigerant is circulating through the system.
If the refrigeration circuit seems to be functioning normally (compressor running, frost or condensation on the high pressure line from the condenser to the evaporator), but no cool air is blowing out of the ducts inside the car (and the blower is working), the fault is likely a BLEND AIR door that is stuck in the HEAT position, or possibly a badly clogged cabin air filter that is restricting airflow. Another possibility would be a fault in the automatic climate control system such as a ad interior temperature sensor or control module.

Sep 28, 2012 | 2007 Ford Ka 1.3

### What are the AC pressures supposed to be on a 2000 Monte Carlo?

On hot day @ 85=+ degrees it should be between 45 to 50 pounds on the low side pressure port

Jul 01, 2011 | 2000 Chevrolet Monte Carlo

### On the dashboard of my 99 deville it says a/c off low refrigerant. how do I turn the ac back on to recharge ? thank you ...

You will need to recharge it to get it to come back on, it has a pressure switch that will prevent operation until the level is brought back up to normal.

Jun 26, 2011 | 1999 Cadillac DeVille

### 1997 jetta ac works for one minute then warm air blows

check the refrigerant level. The compressor is running until the low pressure or high pressure switch switch cuts it off.

Running the unit without enough refrigerant will damage the compressor because the lubricating oil is dissolved in the refrigerant. This is the reason for the low pressure switch cut off--to protect the compressor from damage.

If pressure gets too high, the compressor seals will blow. Thus the reason for the high pressure switch. Too much refrigerant or too much air in the system (due to a leak) will cause high pressures.

If refrigerant level appears to be correct, then suspect trapped air from a leak causing a high pressure cut-off. If refrigerant is low, suspect a leak causing a low pressure cut-off.

Mar 02, 2011 | Volkswagen Jetta Cars & Trucks

### Where is the low pressure port A/C port on a 1997 Lincoln Mark VIII. Be more specific than the smaller port on the larger line as the smaller port on the larger line doesn't fit any of the refrigerant...

LOW PRESSURE PORT HAS A BLUE CAP ON IT.MAKE SURE YOU ARE USING REFRIGERANT R-134 BLUE CHARGE HOSE.R-12 CHARGING HOSE WILL NOT FIT R-134 SYSTEMS.SEE YOUR CAR HAS R-134 REFRIGERANT SYSTEM. THE EARLY 90S CARS HAVE R-12 REFRIGERANT SYSTEM.YOU NEED R-134 CHARGE HOSE SET.

May 29, 2010 | 1997 Lincoln Mark VIII

### AIR conditioner not working again. replaced fan and added freeon(?) after about 1 week no more cold air... what is the problem?

Freon is the common name for the refrigerant R12 and is no longer used. New refrigerant is R134a. Each are as dangerous when it comes to fire, but freon was more dangerous to breathe, as it asphyxiated you while making you so stupid you didn't notice.

More than likely you have a leak in the system if you have no cold air. A state licensed HVAC shop and most mechanic shops will have an A/C evacuation system, which is needed to properly test your system. Simply using a can of refrigerant can easily blow your seals and require you to repair again. It's always best to take it to a shop.

Evac systems will vacuum the coolant out of the system and fill it again to specified pressure. Occasionally the techs will check the pressure & after 3 hours if no change in pressure, you're good to go. Evac system will record how much refrigerant is pulled from your system and you are only charged for what extra is needed to bring to specified pressure... + shop costs/labor.

Stay away from DIY refrigerant in a can and never* depress the stutor valve to check and see if there is refrigerant/ What you do it put moist air into the system (outside pressure is denser/higher than internal pressure of A/C system) when you or your "so-called" mechanic does this, which destroys all* the components in a short period of time.

Get the system repaired ASAP. As little as one humid day out of 2 weeks time is enough to destroy all the components. A closed, sealed system has no* condensation/moisture in it at all

Oct 07, 2009 | 2002 Dodge Grand Caravan

You need to replace the condensor, then take it to a shop to have the a/c system evacuated and recharged to purge moisture because the system was opened. That will cost around \$150. You do not need to replace the receiver/dryer/suction accumulator even though they will tell you that you do.
go to car-part.com to find prices of condensor from salvage yards. Page with asterisk on it is the lowest priced part.

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The Refrigerant Cycle
During stabilized conditions (air conditioning system shutdown), the refrigerant is in a vaporized state and pressures are equal throughout the system. When the A/C compressor (19703) is in operation it increases pressure on the refrigerant vapor, raising its temperature. The high-pressure and high-temperature vapor is then released into the top of the A/C condenser core (19712).
The A/C condenser core, being close to ambient temperature, causes the refrigerant vapor to condense into a liquid when heat is removed from the refrigerant by ambient air passing over the fins and tubing. The now liquid refrigerant, still at high pressure, exits from the bottom of the A/C condenser core and enters the inlet side of the A/C evaporator core orifice (19D990).
The A/C evaporator core orifice is the restriction in the refrigerant system that creates the high pressure buildup in the A/C evaporator core (19860) and separates the high and low pressure sides of the A/C system. As the liquid refrigerant leaves this restriction, its pressure and boiling point are reduced.
The liquid refrigerant is now at its lowest pressure and temperature. As it passes through the A/C evaporator core, it absorbs heat from the passenger compartment airflow passing over the plate/fin sections of the A/C evaporator core. This addition of heat causes the refrigerant to boil (convert to gas). The now cooler passenger compartment air can no longer support the same humidity level of the warmer air and this excess moisture condenses on the exterior of the evaporator coils and fins and drains outside the vehicle.
The suction accumulator/drier (19C836) is designed to remove moisture from the refrigerant and to prevent any liquid refrigerant that may not have been vaporized in the A/C evaporator core from reaching the A/C compressor. The A/C compressor is designed to pump refrigerant vapor only, as liquid refrigerant will not compress and can damage the A/C compressor.
The refrigerant cycle is now repeated with the A/C compressor again increasing the pressure and temperature of the refrigerant.
The A/C cycling switch (19E561) interrupts compressor operation before the external temperature of the A/C evaporator core gets low enough to cause the condensed water vapor (excess humidity) to turn to ice. It does this by monitoring low side line pressure. It is known that a refrigerant pressure of approximately 210 kPa (30 psi) will yield an operating temperature of 0°C (32°F). The A/C cycling switch controls system operation in an effort to maintain this temperature.
The high side line pressure is also monitored so that A/C compressor operation can be interrupted if system pressure becomes too high.
The A/C compressor pressure relief valve (19D644) will open and vent refrigerant to relieve unusually high system pressure.
Clutch Cycling Orifice Tube Type Refrigerant System
Item Part Number Description 1 19E762 A/C charge valve port (low side) 2 19E561 A/C cycling switch 3 19C836 Suction accumulator/drier 4 19703 A/C compressor 5 19D644 A/C compressor pressure relief valve 6 19D594 A/C pressure cut-off switch 7 19E762 A/C charge valve port (high side) 8 19712 A/C condenser core 9 19D990 A/C evaporator core orifice 10 19860 A/C evaporator core 11 — Low pressure vapor 12 — High pressure vapor 13 — Low pressure liquid 14 — High pressure liquid

1. Connect the R-134a A/C Refrigerant Center to the low- and high-pressure service gauge port valves.
2. Evacuate the system until the low-pressure gauge reads at least 99.4 kPa (29.5 in-Hg) (vacuum) and as close as 101.1 kPa (30 in-Hg) as possible. Continue to operate the vacuum pump for a minimum of 45 minutes.
3. Turn off the evacuation pump. Observe the low-pressure gauge for five minutes to make sure that the system vacuum is held. If vacuum is not held for five minutes, leak-test the system, service the leaks, and evacuate the system again.
4. Correctly oil match the system to verify that the correct amount of refrigerant oil is present in the system. For additional information, refer to Refrigerant Oil Adding in this section.
5. Charge the system with the specified weight of refrigerant and refrigerant oil.
6. When no more refrigerant is being drawn into the system, start the engine and select MAX A/C operation. Set the blower motor speed to maximum and allow the remaining refrigerant to be drawn into the system. Continue to add refrigerant into the system until the specified weight of R-134a has been added. Close the charging cylinder valve and allow the system to pull any remaining refrigerant from the hose. When the suction pressure drops to approximately 207 kPa (30 psi), close the charging hose valve.

May 14, 2009 | 1995 Nissan Maxima

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