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condensing units that feel like radiators

Is there any one that is familiar with older lennox condensors? I have a lennox condensor M#hs16-511v-8p. I'm trying to figure out the size of condensor. thanks


  • ddenny
    ddenny Member Posts: 75
    condensing units that feel like radiators

    once and a while I'll get a no a/c call where I'll find nothing wrong mechanically but the condenser just isn't giving up it's heat. the coils don't look dirty. the heat being blown by the condenser fan doesn't seem hot but the condensing unit itself is too warm like a radiator. the liquid line is too warm. obviously not subcooling. on the last unit I had to overcharge the unit in order to get the suction pressure up to around 60#.
    In the past I tried chemical cleaners on the condensing coil to no avail. the unit would work a lot better for 15 or 20 minutes after rinsing it off but the pressure and amperage would soon get too high again. I even tried taking the refrigerant out and replacing it in case there were noncondesables. on the most recent one the guy had a pressure washer but that didn't work either.
    what's the best way to clean a condenser? do I have to get a steam cleaner? thank you
  • clammy
    clammy Member Posts: 2,912
    double row coils

    I also have ran into that promblem and in some cases the condensing unit may have a two row coil and may have to be split to be properly cleaned or chemically cleaned twice to get the coil clean ,what i have found which works well for myself is using a chemical pump sprayer and completly spray down the coil and then wash off with water ,i have found this to be the best method and impacts the least amount of damage to the coils,pressure washer can damage the coils fins and inrease your head pressure making matters worse.Find yourself a non acid ,enviromentally freindly coil leaner ,vapco is probalbly the best around sometimes hard to get but is definetly the best and is non acid.In my experenes alot of times a oil does not look to bad till you clean it and see not only how muh leaner the oil looks but also that your not running high head pressure .Also on another note i would check your return duct work and make sure that your pulling return from the living area and not just over loading the unit by pulling air from a attic or unconditioned spaces.peace and good luck clammy
    R.A. Calmbacher L.L.C. HVAC
    NJ Master HVAC Lic.
    Mahwah, NJ
    Specializing in steam and hydronic heating
  • Empire_2
    Empire_2 Member Posts: 2,343
    Just a thought.

    SOmetimes it is difficult to determine if a double row coil is in place. Take a stick of fos rod and see how thick the coil(s) are. if it's around 2" its a double row. Also feel the discharge from the condenser fsn motor as it should be shooting straight up. If it is only felt on the outter edge, then your coil is probably plugged.

    Mike T.
  • tina_4
    tina_4 Member Posts: 1
    A/C not working, think it's the fan?

    I came home yesterday to a hot house. The A/C pipes had frozen condensation, so I shut the breaker to both the A/C and the furnace.
    This morning I turned on both breakers, and tried turning on the A/C (I changed the furnace filter last night, but it really wasn't very dirty). The A/C unit seems to be running, but no air was coming out of the vents. I tried turning the fan button on the thermostat to "on" from "auto". That originally worked, but I was afraid to leave for work and leave it "on", so I turned it back to "auto". Now my son tells me that the fan won't kick on whether it is turned "on" or on "auto". I had him turn off the A/C so it wouldn't freeze up again.

    Can someone please help me? I try to do all home repairs myself, but I usually don't mess with the furnace or the A/C. BUT, I just found out I am losing my job in a few weeks.

    Any suggestions will be greatly appreciated.
  • Empire_2
    Empire_2 Member Posts: 2,343
    Could be:

    1 of 3 things. Motor could be bad, t-stat could be bad or fan relay is bad. the only way to confirm this is to access your furnace control panel and jumper r to g. this is your fan circuit. only do this once because the outside condenser will come on also. you should hear a click and the motor inside furnace should start up. You really should call for service as this could be dangerous.

    Mike T.
  • Yea, what clammy said about the coil.

    My method is to take a screwdriver and gently spread the fins in a very small area to have a look see down inside there. Then I can see if it's a double (or even triple) and it the inner coil is clogged. You can see the buildup if you look closely in there. And also like clammy said, if you don't take the time to dismantle the unit and split the coils apart from one another you will NEVER get the stuff out of there. It can take several treatments to get all that junk out of there if it's really bad. I can usually get an average sized unit done in less than two hours. The after that make a point of cleaning it like that every 3 years at least.

    The other no air problem does sound like no evap/indoor fan running which could be attributed to any of the above mentioned causes.
  • Empire_2
    Empire_2 Member Posts: 2,343
    Interesting but here is how they rate their coils:

    511 ia a heavy4 ton system. You can move to 4.5 to or even 5 if you would like more dehumidification. ALways use with TXV. 51000BTU/HR.

    MIke T.
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