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What should A/C pressure & temperature be ???

Discussion in 'Gen 3 Prius Care, Maintenance & Troubleshooting' started by lech auto air conditionin, Oct 25, 2019.

  1. lech auto air conditionin

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    1: Question should you allow a mechanic to top off your refrigerant??.

    2: Question what damage could be done with just 2 or 3 ounces over charged refrigerant on a Prius ?

    3: Question what damage could be done allowing the air-conditioning to run very low on refrigerant ?

    4: Question how do I know if a mechanic shop put contaminated refrigerant in my vehicle ?

    5: Question what are the odds of the mechanics recovery and recycling machine been contaminated with moisture and they use that contaminated refrigerant to put back into my car what damage could be done ?

    5: Your car has been in an accident and a body shop repair of your vehicle and then within months your air conditioning compressor burns up. what do you think the most likely cause was ?

    6: is your automotive garage that service your air-conditioning have only the little cans of refrigerant. and they have the cans of refrigerant that contain the stop leak additive plus the UV trace dye, and compressor lubricant. Do you know the answer to this question? And what kind of damage is caused by a shop that uses this kind of refrigerant cans to a Prius compressor ?

    7: Question have you had a mechanic at a shop tell you they will pressure test your system on the air conditioning to see if it has leaks ?. Did they use sharp compressed air from the air hose of the shop. And the other question what kind of damage does this cause if they did ?.

    8: Question did your mechanic shop use a electronica leak detector that has a calibration reference bottle to test whether the leak detector is calibrated and sensitive enough to find a small leak ?. Or was the shop cheap or a knowledgeable enough to even know they should own in possess set a piece of equipment to properly find refrigerant leaks ?.

    9: Question does the shop that looks for leaks on your air-conditioning only use UV trace dye and a UV light to search for leaks ?.

    10: Question this is a simple yes or no. This question makes the difference between you use the shop to service your air-conditioning or you turn around and leave and find another shop. Does the shop that service your air-conditioning use a refrigerant analyzer and can give you a print out or show you the quality of the refrigerant in your car before they recover it?. Is the shop willing if they own a refrigerant analyzer to connect it to your car after they recharge the air conditioning to prove to you you have pure clean gas not contaminated with any other refrigerant or air?.

    11: does your mechanic shop give you a print out using Toyota Tech Stream before performing air-conditioning repairs to prove to you and show with hard data in black-and-white what is failing a test in performance
    ?.
    And if you ask for a after performance test can they show you and give you using Toyotas factory Tech Stream The after comparison showing all the sensors are correctly functioning with the temperature of your evaporator and your air outlet and the pressures and RPM of your compressor with the amp draw ?. If they cannot why?

    12: Question can you shop prove to you without a shadow of a doubt in a print out that they were actually capable of pulling a vacuum below 500 µm to help remove or reduce the amount of moisture in your air-conditioning system?. If not why ?. Another question should you be using the shop if they cannot?.

    There are many other question to ask but I think this is too many already. If you have any particular questions you can ask. Like I took my car in to a shop to get the air conditioning recharged but when I left and it got hot outside the air-conditioning did not work. ( WHY ???. )

    Below is a link to videos part one and part two before and after results the first video shows low refrigerant charge with the pressures and the temperature.
    The second part two video after a re-charge was performed to factory specifications shows the refrigerant pressures and temperatures after.
    The question is if I was topping off your air conditioning system and I said I could tell when it’s full by the pressure and temperature while your car is sitting inside my shop as in the videos below. Why is the pressure on the vehicle with the lower refrigerant charge and the temperature exactly the same as the pressure and temperature of the car with the full refrigerant charge ?.



     
  2. tankyuong

    tankyuong Senior Member

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    Let your mechanic do it’s thing
     
  3. Dxta

    Dxta Senior Member

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    What could be the causes for a prius AC system not working effectively when the car is on READY? The AC seems to cool, only when the vehicle is driven fast(high RPM)? Could it be the AC compressor?
     
  4. lech auto air conditionin

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    Question about “fast high rpm” are you talking about high rpm of the ice gasoline engine? Or high rpm of the compressor because you’re actually using some sort of scan tool to monitor the RPM of the compressor itself?Or high rpm of the compressor because you’re actually using some sort of scan tool to monitor the RPM of the compressor itself? Or associating rpm’s while accelerating fast and traveling fast down the road ?
    If you are talking about engine RPMs in association with compressor speed. Are we talking about a GEN one where the compressor had a physical engaging and disengaging clutch attached to the engine with a belt ?.

    1: Before any diagnostics or testing is performed it must be performed on a known pure charge of refrigerant that is not contaminated with moisture or air or contaminated gas.
    2: since it only takes 2 minutes to 4 minutes recover an entire charge for a Prius especially if it’s low on charge perform that procedure first.
    3: Since you did not open The system to the atmosphere it only takes another 60 seconds to 120 seconds to pull the system close to 500 µm a vacuum.
    4: now at this point it takes less than 30 seconds once you crack open the refrigerant valve to load the system up with a full factory weighed in charge of refrigerant.
    5: now the system is ready To be test driven. And if any Problems in operation persist you can now start with diagnostic procedures.

    If the shop performing these procedures is using a RRR Machine Machine (Recover Recycle Recharge) Big square overpriced underperforming dumb box as I refer to them as. And the shop does not own and religiously use a refrigerant identifier don’t even bother using that shop go find a shop with a refrigerant analyzer there’s too much contaminated refrigerant out there.

    Next if the shop has a refrigerant analyzer there may be a chance it’s a more educated and not so cheap shop they have one of the better machines that have a built-in Micron meter that reads deep vacuum down below the 500 µm region so they can test for moisture contamination and if needed perform a triple evacuate and nitrogen flush to help lower the moisture content from contamination if somebody worked on the vehicle before and then actually read the performance of the elimination of moisture on the micron meter. Only the much better machines have this feature unless they have a standalone handheld micron meter or it’s built into a good set of gauges. This kind of weeds out the lesser shops that you want to avoid.
     
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  5. Dxta

    Dxta Senior Member

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    The vehicle though is a Camry hybrid 2007. The RPM I'm referring to is when the ICE comes on and the car is being driven on the highway. But while it is idling, the cooling effect from the AC system is not effective (not cooling).
     
  6. lech auto air conditionin

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    I would definitely make sure both the fans are working. And before making or trying to diagnose her figure out any problems discharge and recharge the refrigerant system correctly and exactly before making any at Sumption’s or guessing or trying to diagnose anything
     
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  7. Dxta

    Dxta Senior Member

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    Thanks so very much.
    I just got another Camry hybrid come into the shop, with its discharge hose disconnected from the compressor port. On inspections, discovered the discharge port on the compressor where the discharge hose was disconnected, had some form corrosion (greenish stuffs). This for sure, if I'm going to work on it, that compressor would have to be replaced, and probably the condenser, or any other components, after I'm done with inspecting it.

    My question now is, assuming I replaced the compressor, flush the entire AC system, evacuate (vacuum), put the right quantity of ND11 oil, and recharge, assuming all things are OK, won't the AC system come back to life, instead of replacing or overhauling the entire system?
     
  8. lech auto air conditionin

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    Did the customer tell you why the discharge hose was disconnected? Did the customer themselves or another shop try to work on the system?
    Greenish corrosion unusual for Aluminum. If the aloe minium surface where the O-ring seals it are pitted from corrosion that would be a leak source then you would be replacing the compressor. Sounds like you live near the coast by salt or in a place where they salt the roads in the winter time.

    If you do not know the reason why somebody physically remove the discharge hose when you remove the compressor put it upside down and try to remove some of the oil to see if there’s metal flakes in it or a lot of dirt in If you do not know the reason why somebody physically remove the discharge hose when you remove the compressor put it upside down and try to remove some of the oil to see if there’s metal flakes in it. Possibly somebody started working on it because the compressor burned up and this is what you’re trying to identify. You could put some brake cleaner or carburetor cleaner lacquer thinner or alcohol inside the old compressor you’re going to replace. Shake it up and poured out into a clean dish or glass to see if any small metal flakes come out.

    If it comes out dirty then there’s a lot more stuff stuck inside the condenser that you’re about to replace. If it comes out clean your condenser should be clean internally. And the one where you could find this out if it has the desiccant bag and filter connected permanently to the side of the condenser remove that put back on the That held the desiccant bag. Now with the condenser disconnected at both inlet and outlet ports in Inject some AC flush backwards through the condenser so it blows through and comes into your hand holding some white rags or tissue paper. If it comes out clean you’re good to go you could reuse the condenser as long as there’s no leaks in the condenser. If it comes out dirty you replace it. If it was clean don’t forget to purchase a new desiccant bag to insert back into the condenser but you do that last just before putting it on vacuum because you do not want the desiccant bag exposed to the atmosphere for the absolute shortest amount time possible.

    On that year model Camry is the expansion valve located outside in the engine compartment on the firewall where you can easily remove it and flush through the evaporator?.

    Also if you’re getting a brand new Denzel compressor at least here they come with a full charge of refrigerant oil for the vehicle so you will not have to purchase any more ND-11 oil but this you will have to confirm with the manufacture of the compressor or supplier.

    After that when you re-charge it everything should work unless there were some other underlying electrical or control problem but Mechanically you got everything in good operating condition.
     
  9. Dxta

    Dxta Senior Member

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    Some shop tried or so to work on the system, but owner too brought the car to my shop, for another issue dealing with the transmission system. That has being fixed now. But I'd carry out your suggestions Tomorrow, and possibly get some pictures.

    I live in Lagos, Nigeria, so we don't have issues with salts ...

    The green stuffs on the O seal on the port of the compressor could be moisture.

    Thanks once again for your time.