Help With High pressure reading

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Munson1
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Help With High pressure reading

Post by Munson1 »

Last week I took a long drive and noticed 45 minutes into my trip that Mist was coming out of my vents, after I smelled chemicals so I shut the ac off an found an automotive store and put in some refrigerant,Afterward I never smelled or seen the vapor again.I never changed my cabin filter(8 years) till today. I picked up a set of gauges to check both the high and low side.Compressor turns on for 9 seconds and turns off for 4 seconds.I found an Acura A/C chart for high-low and it seems like my numbers are off.Does anyone have a chart For CRV?

74 degrees(75 degree chart)

Humidity 80

Suggested reading

Low. High. Temp. Cabin

25-37. 84-155. 43 degrees output

Actual Reading

26-40. 150-170 43/46degrees

My low reading of 26 is compressor on and 40 is compressor off.For high it’s 170 compressor on(then drops) and 150 compressor off.

While the compressor is running the high hits 170 and starts dropping before the compressor shuts off.Is This normal?

Static reading
H—L

84 85
I’m going to clean the condenser with some coil cleaner.
Do I have a defective Drier packet?or expansion valve?or do these numbers look normal?

I tested the system again after coil clean and taking a 1/2 hour drive.The Acura levels suggested ;76-85 degrees 80% humidity

Suggested reading

Low. High. Temp Cabin

27-42. 128-181. 52.Degrees

Actual

29-40. 175-195 46 Degrees

82Degrees

So the Low side with the compressor engaged is 29PSI and the high side with compressor engaged and high settling is 195 @Idle .I’m not sure if Acura would be “Accurate” for CRV ..pun intended but the high side is slightly over the limits.Is this anything to worry about?
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JohnHere
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Re: Help With High pressure reading

Post by JohnHere »

A low refrigerant charge will cause mist and odors to emanate from the vents under certain temperature and humidity conditions. The low charge could be due to either accumulated seasonal losses or a leak. You installed an unknown amount of refrigerant back into the system, and by sheer luck, temporarily brought the charge back up to where the system would work normally again.

What year is your CR-V?
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Munson1
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Re: Help With High pressure reading

Post by Munson1 »

JohnHere wrote: Sat Aug 07, 2021 11:10 am A low refrigerant charge will cause mist and odors to emanate from the vents under certain temperature and humidity conditions. The low charge could be due to either accumulated seasonal losses or a leak. You installed an unknown amount of refrigerant back into the system, and by sheer luck, temporarily brought the charge back up to where the system would work normally again.

What year is your CR-V?
It is a 2013
I think I know why there was a leak and/or what the leak was. A week before all this happened I checked the low pressure with one of those automotive store low side cages. I thought the pressure was low because the compressor was kicking off only for four seconds. I realized today by doing that I disturbed the low port Schrader valve. And that is what has been leaking. I tightened the cap over the low port and it seems to hold now. I was just curious to know what the pressures should be at idle, or if the pressures I have are good.I totally forgot I touched it.I I’ve been trying to get all my maintenance done like oil/trans fluid/filters and this before the fall comes. So I think it was a self-induced weeks. I hope that secondary Keeps the pressure .Thank you
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Re: Help With High pressure reading

Post by JohnHere »

Munson1 wrote: Sat Aug 07, 2021 12:21 pmIt is a 2013
All three models of that year CR-V take 15 ounces (net weight) of R-134a and 3.7 (fluid) ounces of PAG-46 oil, both very small amounts. So just an ounce or two short of refrigerant will definitely affect cooling performance.
Munson1 wrote: Sat Aug 07, 2021 12:21 pm I think I know why there was a leak and/or what the leak was. A week before all this happened I checked the low pressure with one of those automotive store low side cages. I thought the pressure was low because the compressor was kicking off only for four seconds. I realized today by doing that I disturbed the low port Schrader valve. And that is what has been leaking. I tightened the cap over the low port and it seems to hold now.
Maybe you caused the seepage and maybe you didn't. It's not unusual for the Schrader valves to leak slightly under normal circumstances. The Schrader actually is considered the secondary seal while the cap is the primary seal. So if your low-side cap has an undamaged o-ring inside and is in good shape otherwise (no cracks, stripped threads, etc.), it should seal just fine. Spray some water mixed with a little diswashing liquid around the area. No bubbles means that it's sealed.
Munson1 wrote: Sat Aug 07, 2021 9:44 am So the Low side with the compressor engaged is 29PSI and the high side with compressor engaged and high settling is 195 @Idle .I’m not sure if Acura would be “Accurate” for CRV ..pun intended but the high side is slightly over the limits.Is this anything to worry about?
Munson1 wrote: Sat Aug 07, 2021 12:21 pm I was just curious to know what the pressures should be at idle, or if the pressures I have are good.I totally forgot I touched it.I I’ve been trying to get all my maintenance done like oil/trans fluid/filters and this before the fall comes. So I think it was a self-induced weeks. I hope that secondary Keeps the pressure .Thank you
To measure the pressures correctly using a Manifold Gauge Set and at maximum heat load, the engine should be at a fast idle or around 1,800 RPM, windows and doors open, system set on max cool, blower on high, compressor engaged, and engine-bay fan(s) running at full speed. At the same time, note the ambient temperature, preferably one-foot in front of the grille. As a rule of thumb, the high side should be approximately 2.2 to 2.4 times the ambient temperature.

As said, I think the cap will seal just fine as long as it's physically intact. If not, replacements and anything else you might need are readily available from this site's sponsor.

The last set of pressures and (center?) vent temp that you posted (29/195/46 degrees) look pretty good, although they were measured at idle speed. Both pressures and vent temp should drop a bit if you test as above.

If it's performing and cooling well now and doesn't leak anymore, you'll probably want to leave it alone. I would, too. But if you'd like to check the pressures again, follow the procedure above and post back anytime.
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Munson1
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Re: Help With High pressure reading

Post by Munson1 »

JohnHere wrote: Sat Aug 07, 2021 2:18 pm
Munson1 wrote: Sat Aug 07, 2021 12:21 pmIt is a 2013
All three models of that year CR-V take 15 ounces (net weight) of R-134a and 3.7 (fluid) ounces of PAG-46 oil, both very small amounts. So just an ounce or two short of refrigerant will definitely affect cooling performance.
Munson1 wrote: Sat Aug 07, 2021 12:21 pm I think I know why there was a leak and/or what the leak was. A week before all this happened I checked the low pressure with one of those automotive store low side cages. I thought the pressure was low because the compressor was kicking off only for four seconds. I realized today by doing that I disturbed the low port Schrader valve. And that is what has been leaking. I tightened the cap over the low port and it seems to hold now.
Maybe you caused the seepage and maybe you didn't. It's not unusual for the Schrader valves to leak slightly under normal circumstances. The Schrader actually is considered the secondary seal while the cap is the primary seal. So if your low-side cap has an undamaged o-ring inside and is in good shape otherwise (no cracks, stripped threads, etc.), it should seal just fine. Spray some water mixed with a little diswashing liquid around the area. No bubbles means that it's sealed.
Munson1 wrote: Sat Aug 07, 2021 9:44 am So the Low side with the compressor engaged is 29PSI and the high side with compressor engaged and high settling is 195 @Idle .I’m not sure if Acura would be “Accurate” for CRV ..pun intended but the high side is slightly over the limits.Is this anything to worry about?
Munson1 wrote: Sat Aug 07, 2021 12:21 pm I was just curious to know what the pressures should be at idle, or if the pressures I have are good.I totally forgot I touched it.I I’ve been trying to get all my maintenance done like oil/trans fluid/filters and this before the fall comes. So I think it was a self-induced weeks. I hope that secondary Keeps the pressure .Thank you
To measure the pressures correctly using a Manifold Gauge Set and at maximum heat load, the engine should be at a fast idle or around 1,800 RPM, windows and doors open, system set on max cool, blower on high, compressor engaged, and engine-bay fan(s) running at full speed. At the same time, note the ambient temperature, preferably one-foot in front of the grille. As a rule of thumb, the high side should be approximately 2.2 to 2.4 times the ambient temperature.

As said, I think the cap will seal just fine as long as it's physically intact. If not, replacements and anything else you might need are readily available from this site's sponsor.

The last set of pressures and (center?) vent temp that you posted (29/195/46 degrees) look pretty good, although they were measured at idle speed. Both pressures and vent temp should drop a bit if you test as above.

If it's performing and cooling well now and doesn't leak anymore, you'll probably want to leave it alone. I would, too. But if you'd like to check the pressures again, follow the procedure above and post back anytime.
Thank you for the information and for helping me.I tightened the cap on top of the schrader valve and placed a balloon over the port sealed with a rubber band.As long as it holds and no damage happens to the system then I’m happy.And once again thank you and everyone else who helped,
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