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  1. #53
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    Quote Originally Posted by hvacskills View Post
    Here is a question for you .....

    What about the flow of the refrigerant through a condensing coil ? ... suppose the flow of the refrigerant is impeded / slowed by a partial blockage at the metering device, say a capillary tube system without a receiver, without the refrigerant flowing at the proper speed through the condensing coil, constantly coming in contact with a cooler surface, do you think that could be part of the reason to have an elevated highside pressure, along with the compressor constantly pumping hot gas into the condensing coil, so long as there is still an adequate amount of refrigerant coming back to the compressor, in some instances ?

    .... I am assuming condensing coils are designed for the refrigerant to travel through the tubing at a certain speed, also assuming condensing coils are designed to be just barely large enough to function within a set operating temperature range ....

    sort of how newer coils are ' rifled ' to increase the tumbling affect of the refrigerant to increase contact / heat transfer, except now the opposite is happening

    hope you don't mind OP
    An elevated condensing pressure has more to do with the available surface area for heat exchange in the condenser than anything related to the velocity of the gas going through it.

    In a system with a restriction somewhere in the liquid stream, there will less refrigerant in the evaporator and more going to the high side. In a system with no receiver it will tend to stack up in the condenser, reducing the available condensing surface area. This is what causes the rise in pressure.

  2. #54
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    Quote Originally Posted by icemeister View Post
    An elevated condensing pressure has more to do with the available surface area for heat exchange in the condenser than anything related to the velocity of the gas going through it.

    In a system with a restriction somewhere in the liquid stream, there will less refrigerant in the evaporator and more going to the high side. In a system with no receiver it will tend to stack up in the condenser, reducing the available condensing surface area. This is what causes the rise in pressure.
    ok, to expand a lttle further .... I believe I have seen it both ways with a cap tube system .... where the highside is elevated due to restriction, and where the highside has lowered due to a restriction ... do you imagine there is a balance point, with a few factors involved, IE ... ambient temperature, cleanliness of coil, size of restriction, system charge ... to where the refrigerant can condense fast enough, although it may be stacking in the condensing coil, to outpace a rise in head pressure ?
    "All that is necessary for the triumph of evil is that good men do nothing." (hvacrskills)


    II CORINTHIANS 3:6

    “Who also hath made us able ministers of the new testament; not of the letter, but of the spirit: for the letter killeth, but the spirit giveth life.”

    the spirit of the law

    The intended meaning of a law by those who wrote it, as opposed to a literal interpretation thereof.

  3. #55
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    Quote Originally Posted by hvacskills View Post
    ok, to expand a lttle further .... I believe I have seen it both ways with a cap tube system .... where the highside is elevated due to restriction, and where the highside has lowered due to a restriction ... do you imagine there is a balance point, with a few factors involved, IE ... ambient temperature, cleanliness of coil, size of restriction, system charge ... to where the refrigerant can condense fast enough, although it may be stacking in the condensing coil, to outpace a rise in head pressure ?
    Where the condensing pressure will settle out depends a lot on how much refrigerant is in the system. Typically, with the original factory charge the pressure will be lower than normal simply because the load on the system has been greatly reduced. If there has been a significant amount of refrigerant added...ie, enough to stack up liquid in the condenser...then the pressure will tend to increase greatly.

  4. #56
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    Quote Originally Posted by icemeister View Post
    Where the condensing pressure will settle out depends a lot on how much refrigerant is in the system. Typically, with the original factory charge the pressure will be lower than normal simply because the load on the system has been greatly reduced. If there has been a significant amount of refrigerant added...ie, enough to stack up liquid in the condenser...then the pressure will tend to increase greatly.
    way off topic here but been wanting to ask you this ..... the sub solar point, or Lahaina Noon, is coming soon for you I believe, supposedly objects, especially vertical objects, when they cast no shadow and look somewhat weird when the Sun is directly overhead, have you experienced this ? the Sun is never directly overhead in the Continental United States
    "All that is necessary for the triumph of evil is that good men do nothing." (hvacrskills)


    II CORINTHIANS 3:6

    “Who also hath made us able ministers of the new testament; not of the letter, but of the spirit: for the letter killeth, but the spirit giveth life.”

    the spirit of the law

    The intended meaning of a law by those who wrote it, as opposed to a literal interpretation thereof.

  5. #57
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    We touched on this subject a while back and I mistakenly stated that where I am the sun is directly overhead every day, but you're correct in that there are two days each year when we have a "Day of No Shadows" at the Equinox.

    At or near the equator, the seasonal change in the angle of the sun due to the tilt of the earth's axis relative to the sun is very small as compared to what one would see in the US.

    This also explains the small change in the times for sunrise and sunset here as well, which are roughly at 6:20 AM and 6:20 PM every day, all year long. I haven't yet found any mention of why there's that lag of 20 minutes.

  6. #58
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    Maybe your location is 20 minutes from the equator?

    Latitude is: Degrees / Minutes / Seconds

    PHM
    ----------



    Quote Originally Posted by icemeister View Post
    We touched on this subject a while back and I mistakenly stated that where I am the sun is directly overhead every day, but you're correct in that there are two days each year when we have a "Day of No Shadows" at the Equinox.

    At or near the equator, the seasonal change in the angle of the sun due to the tilt of the earth's axis relative to the sun is very small as compared to what one would see in the US.

    This also explains the small change in the times for sunrise and sunset here as well, which are roughly at 6:20 AM and 6:20 PM every day, all year long. I haven't yet found any mention of why there's that lag of 20 minutes.
    PHM
    --------
    The conventional view serves to protect us from the painful job of thinking.

  7. #59
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    Quote Originally Posted by icemeister View Post
    We touched on this subject a while back and I mistakenly stated that where I am the sun is directly overhead every day, but you're correct in that there are two days each year when we have a "Day of No Shadows" at the Equinox.

    At or near the equator, the seasonal change in the angle of the sun due to the tilt of the earth's axis relative to the sun is very small as compared to what one would see in the US.

    This also explains the small change in the times for sunrise and sunset here as well, which are roughly at 6:20 AM and 6:20 PM every day, all year long. I haven't yet found any mention of why there's that lag of 20 minutes.

    60 minutes in an hour, 24 hours in a day = 1,440 minutes

    1,440 minutes / 360 degrees = 4 minutes per degree .... keep your watch set where it is and travel 5 degrees, roughly 345 miles, East
    "All that is necessary for the triumph of evil is that good men do nothing." (hvacrskills)


    II CORINTHIANS 3:6

    “Who also hath made us able ministers of the new testament; not of the letter, but of the spirit: for the letter killeth, but the spirit giveth life.”

    the spirit of the law

    The intended meaning of a law by those who wrote it, as opposed to a literal interpretation thereof.

  8. #60
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    Quote Originally Posted by icemeister View Post
    We touched on this subject a while back and I mistakenly stated that where I am the sun is directly overhead every day, but you're correct in that there are two days each year when we have a "Day of No Shadows" at the Equinox.

    At or near the equator, the seasonal change in the angle of the sun due to the tilt of the earth's axis relative to the sun is very small as compared to what one would see in the US.

    This also explains the small change in the times for sunrise and sunset here as well, which are roughly at 6:20 AM and 6:20 PM every day, all year long. I haven't yet found any mention of why there's that lag of 20 minutes.
    Back when they invented the clock, they were 20 minutes off.
    If you were a real tech, you'd solder a relay on that board and call it good to go.

    I do a triple evac with nitro to remove non condensables.

    I use 56% silver on everything except steel.

  9. #61
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    Quote Originally Posted by Poodle Head Mikey View Post
    Maybe your location is 20 minutes from the equator?

    Latitude is: Degrees / Minutes / Seconds

    PHM
    ----------
    Actually, now that you mention it, it dawned on me that the 20 minutes is simply a matter the my longitude of 79 deg 50' 16" W relative to the time zone I'm in...which is the same a NYC is the US.

    My latitude of 2 deg south of the equator would be what accounts for for any seasonal change in sunrise and sunset, wouldn't it?

  10. #62
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    Quote Originally Posted by icemeister View Post
    Actually, now that you mention it, it dawned on me that the 20 minutes is simply a matter the my longitude of 79 deg 50' 16" W relative to the time zone I'm in...which is the same a NYC is the US.

    My latitude of 2 deg south of the equator would be what accounts for for any seasonal change in sunrise and sunset, wouldn't it?
    since the Earth is tilted on it's axis, with the tilt being towards the Sun at times and away from the Sun at other times, I believe any seasonable change in sunrise and sunset is inescapable on this planet regardless where you are located

    all I know is you get summer twice a year and in Cleveland we barely even get one
    Last edited by hvacskills; 03-14-2019 at 12:03 PM.
    "All that is necessary for the triumph of evil is that good men do nothing." (hvacrskills)


    II CORINTHIANS 3:6

    “Who also hath made us able ministers of the new testament; not of the letter, but of the spirit: for the letter killeth, but the spirit giveth life.”

    the spirit of the law

    The intended meaning of a law by those who wrote it, as opposed to a literal interpretation thereof.

  11. #63
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    The “no shadow” affect is know as solar noon and has nothing to do with your distance from the equator. The only place that experience a solar noon in us is Hawaii.


    Sent from my iPhone using Tapatalk

  12. #64
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    Quote Originally Posted by Core_d View Post
    The “no shadow” affect is know as solar noon and has nothing to do with your distance from the equator. The only place that experience a solar noon in us is Hawaii.


    Sent from my iPhone using Tapatalk
    Ahhh...The Zenith !

  13. #65
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    amazing how the Earth hangs in a somewhat precarious balance

    "All that is necessary for the triumph of evil is that good men do nothing." (hvacrskills)


    II CORINTHIANS 3:6

    “Who also hath made us able ministers of the new testament; not of the letter, but of the spirit: for the letter killeth, but the spirit giveth life.”

    the spirit of the law

    The intended meaning of a law by those who wrote it, as opposed to a literal interpretation thereof.

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