I need some information on what the correct pressure is on the low pressure port for AC in these cars. System was vacuumed for an hour before the attempt to recharge. Low pressure is about 20 psi and high pressure is about 150 psi. I am trying to diagnose an AC problem and have a basic question. ... Ac work is not a … No change in low side and high side pressures, the pressures are still equal. First, it’s critical to know if the compressor is operating or not. If both the high and the low side are below these readings then you may need to add refrigerant. Pressure that is too much lower or higher shows there is a problem. You can begin testing with only 45 psi. Mercury Mechanic: Dieseljunky2 , Mercury Technician replied 10 years ago The low side is at the lowest acceptable pressure for your outside temp with 28 degree discharge air. Initially the pressure read 45 psi which would suggest that the system was probably about where it should be given the ... All I have done at this point is observe the pressure on the low side of A/C system and witnessed the compressor stopping when the ... You really need gauges for both the high and the low side to service a modern AC system. The garage thinks I either have a crimped line … E. Enabled Veteran Member. Compressor staying engaged, radiator fans both working, low side tube isnt cool at all, even somewhat warm. It should be at 220psi. If its cold out the compressor will run for a little bit, but if its warm out the compressor will not even kick on. 65°F Ambient temperature: Low side pressure 25-35 psi High side pressure 135-155 psi 70°F Ambient temperature: Low side pressure 35-40 psi High side pressure 145-160 psi 75°F Ambient temperature: Low side pressure 35-45 psi High side pressure 150-170 psi 80°F Ambient temperature: Low side pressure 40-50 psi High side pressure 175-210 psi As for high side pressures, your looking for a pressure that is about 20 deg F above outdoor ambient air that is entering the condenser. 05-28-2004, 11:11 AM. Except in the real world it blows modestly cooled air vice cold air. The high side does not move and it is at 30psi. For a high pressure gauge when the high pressure reading is 200 to 225 psi for R12 or 225 to 250 psi for 134a, the system is fully charged. Looking for GRAINGER APPROVED Pressure Switch, 5 Open (PSI), Opens On Low Pressure, 5 to 20 Differential Pressure (PSI), SPST (6ALA2)? R134a Pressure Gauge Chart This chart details how ambient temperature correlates with the system refrigerant charge pressure, and how it affects high and low side psi readings. By the time the refrigerant reaches these lines it has lost most of its heat and has collapsed into a liquid state, taking up less volume. Compressor turns off then slowly goes back to about 30 psi. Did lose an ounce … For R410A it should be around 115-120 psi. There are two bolts that hold the dryer cylinder in place on the side—remove the two bolts and pull it up just enough to access the low pressure valve. Any ideas on what could be causing this, … I''m thinking it''s the evaporator. I have about 50-55 psi at 95F outside temperature. Relevance. Low and High Side Pressure the Same. When running high side is like 150-175psi low side is between 25-35psi . It can be used for recharging refrigerant, or to diagnose an a/c system based on pressure readings from your gauges. michael k. Lv 4. 4. Items to note:-it does cool OK, but given that it's only low 80s now, I can tell it should do more The condensor works properly. The low pressure valve is located under the hood on the passenger side, in the rear corner, tucked underneath either the dryer cylinder or a fuse box, depending on which model truck you have. The AC has been checked over 3 times with no problems reported. whats the issue and how do i fix it? I'm not sure what the low threshold is for the pressure switch (to still allow A/C on), but I would assume much under 70psi. Warning: Remember, venting 134a refrigerant into our atmosphere is illegal and bad for our environment. A/C compressor goes on and low side goes into vacuum. For a gas turbine the pressure ratio may be in the range: A 2 to 3 B 3 to 5 C 16 to 18 D 18 to 22 . High side stays around 100 to 120 psi. I have 97 Windstar, 3.8L in which the AC has quit working. With the first 12 oz can it was already at 200 psi and 10 psi low, then after the second it was at 315 psi, low side 20 psi, i left the 3rd can at half and now its at around 30 psi but 390 psi high side. something isn't right. To be safe, turn off the recharge kit's release valve as soon as the pressure reaches the lower extremes of adequate pressurization levels. it was showing just 21 psi, as pressure was increased the ac cycled off and on even more often. Low Pressure and High Pressure Readings If you are using a low pressure gauge when the low pressure reading is between 25 psi and 40 psi, the system is fully charged. The low pressure side of of my Toyota Camry AC shows the correct amount of coolant (psi) until the compressor kicks in and then the guage shows a sudden pressure drop to 5 PSI. There are brand new expansion valves so those have been factored out as the problem. Price $10.38. I am working on an air conditioner, fixed the leak, charged system, low side pressure at 62 psi, high side at 150 psi, ambient temperature at 74f,I add more refrigerant, low side at 72 psi and high side a 170 psi, system won't take more refrigerant,if I add more low pressure stays the same, help. CRITICAL. AC low pressure at 20 psi The high pressure is fine but the low pressure is about half what it should read at 20 psi. 4 Answers. The system should be about 25 to 30 psi on the low side and 200 to 250 psi on the high side. I'm not sure if your Lancer is equipped with a high-side pressure switch but the same principle applies. The high-side pressure, which the FSM gives only somewhat roughly as higher than 2xx psi (my GM manuals have pressure tables based on humidity and ambient temp, it changes a lot), never goes above about 150 psi at 1500 rpm as specified. It kicks the compressor on and off between 26 and 30 psi. 115 -120 PSI Low Pressure 410 -420 PSI High Pressure. AC Low Side Pressure Too High (70 psi) fdunford. I'm guessing there is a restrict somewhere. Expansion valve and compressor already replaced. Price $7.91. If the ambient temperature is higher or lower than normal (70 to 80°F) the pressures will go up or down accordingly. AC isn't performing as it should, in cab air flow should be about 20 degrees colder. High side tube is hot. I measured the pressure at 70 psi on the low side which is way too high. The high side has way too much pressure. Easy online ordering for the ones who get it done along with 24/7 customer service, free technical support & more. Easy online ordering for the ones who get it done along with 24/7 customer service, free technical support & more. the shop is telling me it should be around 35 psi on the low side and that i have a bad pressure … Trying to fix my a/c on an 03 sebring and when i put the hose for the 134 refrigerant on it the pressure gauge reads 150 psi. Step 3: Observe the pressure readings. Grainger's got your back. Also a brand new trinary switch. Measure static pressure with the engine off and AC not run for at least one hour. The low-side should be near 30 PSI at 90 degrees Fahrenheit or less. Enjoy your ice-cold AC! ... 75°F Low side pressure 35-45 psi High side pressure 150-170 psi 80°F Low side pressure 40-50 psi High side pressure 175-210 psi The following table presents the possible inferences and the actions that can be taken, based on the level of pressure registered by the high and low pressure gauges: Another sanity check is that the low-pressure switch activates at 32 psi, which is lower than the 40 psi you are seeing on the low-side. The low-pressure side, when connected to the gauge, should read less than 100 psi. AC Low side reading 110 psi with compressor off....what? I let out all the frion. Though every air conditioning system will vary, you want to see the high side pressure around 20 psi and the low side around 40 psi. My ac builds up pressure to about 100 psi on the low side, which causes the compressor to kick off. BOSTITCH Pancake Air Compressor, Oil-Free, 6 Gallon, 150 PSI (BTFP02012) & Accessory Kit, 17 Piece Compressor Inflation Kit, with Blow Gun, Air Chucks, & Inflation Needles 5.0 … That allows the high and low pressures to equalize. You won't get any cold air, but you should should start to see some compressor engagement. Dealer promptly tells wife that she cannot use AC or compressor will make car stall out. a/c low pressure cap reading 150 psi? PSI is the common measurement for pressure used in terms of pounds per square inch. Looking for GRAINGER APPROVED Pressure Switch, 10 Open (PSI), Opens On Low Pressure, 10 to 25 Differential Pressure (PSI) (6ALA3)? Normal rest pressure (system off) is around 100 psi. On a properly working system, high-side pressure will be about twice the ambient temperature, plus 50 PSI. 3. Find Jobs. TThe low pressure AC switch is a 3-way pressure switch in the low-side refrigerant line. On 2011-04-25 by Vidyadhara Seethur . Knowing just the low side reading doesn’t tell us much, but with some more info we might be able to get some idea what’s going on. Answer Save. The low-pressure gauge should read between 25 and 40 psi (pounds per square inch). Low side pressure is around 130 and high side around 150 PSI. I asked the R134a level to be checked, they fill up 1 pound and say AC Compressor/ Accumulator needs to be changed. Typical high side pressure for R410A is < 600 psi at an ambient outdoor temperature of 95 °F, may vary by equipment. There is also brand new low pressure and high pressure switchs. Note: The most ideal pressure readings are around 150 high and 30 low. Thanks. Upvote (9) Downvote (0) Reply (0) ... How much pressure is needed in inverter ac 410 a gas in running? 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