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  1. #14
    Join Date
    Apr 2004
    Posts
    7,680
    The low suction with low superheat along with a low head and probably low subcooling indicate low load. (Poor Airflow). Rather than beat around the bush, measure the actual airflow, not the amount of curtain movement.

  2. #15
    Join Date
    Jul 2006
    Location
    NW burbs of Detroit
    Posts
    6,058
    [QUOTE=docholiday;1901124]The low suction with low superheat along with a low head and probably low subcooling indicate low load. (Poor Airflow). Rather than beat around the bush, measure the actual airflow, not the amount of curtain movement.[/QUOTE
    The head is not low. It's 175.

  3. #16
    Join Date
    Apr 2008
    Location
    Greenwood Lake, ny
    Posts
    49
    I am a newbee trying to do it right so forgive me.
    The indoorcoil was not frozen only suctionline has lot of frost
    at outdoor at the time and onsideof compressor. Could it be
    that the day was not a heavy load . to me it seemed it may be
    over charged not sure. customer said unit has bin working
    noproblems and cooled house. looked at fan speed it was set at
    med high could that have bin problem that not enough air movment
    over indoor coil.

  4. #17
    Join Date
    Jan 2004
    Location
    Lancaster PA
    Posts
    67,760
    Its possible that its a low load problem.
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    How many times must one fix something before it is fixed?

  5. #18
    Join Date
    Jul 2006
    Location
    NW burbs of Detroit
    Posts
    6,058
    Quote Originally Posted by kw10925 View Post
    I am a newbee trying to do it right so forgive me.
    The indoorcoil was not frozen only suctionline has lot of frost
    at outdoor at the time and onsideof compressor. Could it be
    that the day was not a heavy load . to me it seemed it may be
    over charged not sure. customer said unit has bin working
    noproblems and cooled house. looked at fan speed it was set at
    med high could that have bin problem that not enough air movment
    over indoor coil.
    If that is a half horsepower motor than it is moving too slow.

    If you are icing heavy than the coil is probably froze too. Recheck the underside to be sure.

    Turn the furnace on to get a good inside load to get usable readings.

  6. #19
    Join Date
    Apr 2008
    Location
    Greenwood Lake, ny
    Posts
    49
    How do you check indoor coil to see if it is dirty.
    I looked at the top looked clean. Filters were clean also.
    I did clean OD unit. Its rheem/ruud.

  7. #20
    Join Date
    Jan 2005
    Location
    35 miles from Tunica (casinos)
    Posts
    151
    The easiest way to explain checking the coil is look between the air filter and the coil. This sometimes gets tricky and I have actually had to pull coils to check. But I think previous posts are about to center in on the problem. A dirty i/d coil will cause low a/f and everything else mentioned.

  8. #21
    Join Date
    Jun 2008
    Location
    south central pa
    Posts
    133

    Cool

    Quote Originally Posted by kw10925 View Post
    How do you check indoor coil to see if it is dirty.
    I looked at the top looked clean. Filters were clean also.
    I did clean OD unit. Its rheem/ruud.
    good diagnostics starts with good practices. the reason why i mention this is if you were running a 55 with a 6-7* s/h your line temp would be 37 or 38 and we all know that water freezes at 32 so how could there be frost? your probably running no super heat and your meter is picking up heat either from the sun or not being insulated. there are many different manufactures of meters and temp probes personally i use fluke 902 meter with their pipe clamp probe. if i dont cover the probe when i take my readings in direct sunlight will be several degees
    higher.
    now back to the problem its probably low airflow but the only way to find out is to perform a cfm check. theres equations that will require you to take some temp readings in the ductwork its very simple and takes about 10-15 min. to do.i dont know how technical i can get since im not a pro yet but if you do your research youll find it. you should be moving at least 350 cfms if its an older unit you might want to set it at 400. once youve verified that then you can start your diagnosing.
    i wouldnt worry about your head pressure to much its not that far of from where it should be. your compressor should run a 3:1 compression ratio which would be 165 and ruuds tend to run a slightly higher head especially if they were installed with a 5/16 liquid line. and as far as it being a low load thats not going to be the case here. yes at his readings it should be 14-16 for most manufactures but ruuds s/h chart that is located on the inside of the door (which can be some what weird at first to use) is generally a higher s/h than other manufactures. hope this helps.

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