Results 1 to 7 of 7
  1. #1
    The coil on my inside unit is freezing up and I am trying to find the fix. So far what I have came up with is, I am either low on freon, dirty coil, freon leak, or thermostat on inside unit(but unlikely). I had a friend that does HVAC on the side come buy and check my freon and it was at 20psi so he filled it to 65psi, but didn't test it for leaks. It seemed to take care of the problem for a few hours but then it went down again. I thought my coil was clean but after inspecting it better the under side of it looks gummed up with black gunk between the coils. I have tried to spray some houshold cleaners in it to atleast break it up some with little success. The fins look good(not bent). I am going to get some real coil cleaner and was curious what is good to use? Also, what does it take to remove the coil and clean it? If I unhook it will freon blow out everywhere(providing that it hasn't leaked out)or is there some kind of valve that keeps the freon in(I'm sure it is unlikely)?

    Also, I don't have the proper guages so if I was to use a tire guage and test the pressure on the freon will I get some kind of idea how much is there? I don't need an accurate reading. I am mainly trying to see if the freon that was put in leaked out. Thanks, Chad


  2. #2
    without a subcooling and superheat reading we can only do what your doing, come up with a whole bunch of things that can be wrong and your on the right tract.
    so give us superheat,subcooling,head and suction pressure and we will tell you the correct answere.

  3. #3
    Join Date
    Aug 2003
    Location
    Fort Worth, TX
    Posts
    11,320
    Originally posted by stangtamer
    The coil on my inside unit is freezing up and I am trying to find the fix. So far what I have came up with is, I am either low on freon, dirty coil, freon leak, or thermostat on inside unit(but unlikely). I had a friend that does HVAC on the side come buy and check my freon and it was at 20psi so he filled it to 65psi, but didn't test it for leaks. It seemed to take care of the problem for a few hours but then it went down again. I thought my coil was clean but after inspecting it better the under side of it looks gummed up with black gunk between the coils. I have tried to spray some houshold cleaners in it to atleast break it up some with little success. The fins look good(not bent). I am going to get some real coil cleaner and was curious what is good to use? Also, what does it take to remove the coil and clean it? If I unhook it will freon blow out everywhere(providing that it hasn't leaked out)or is there some kind of valve that keeps the freon in(I'm sure it is unlikely)?

    Also, I don't have the proper guages so if I was to use a tire guage and test the pressure on the freon will I get some kind of idea how much is there? I don't need an accurate reading. I am mainly trying to see if the freon that was put in leaked out. Thanks, Chad

    Don't have the moonlighter back. Don't try to pull the indoor coil yourself. You can't legally touch the refrigeration side of your system without EPA certification (i.e. do anything that may cause freon to vent to the atmosphere). Spraying anything onto an evap coil without pulling it and rinsing it out is largely ineffective.

    Hire a licensed, EPA certified pro, tell him what's been done so far, have him do a proper coil cleaning, as well as the indoor blower wheel (also likely as dirty as the coil). He will likely also find the system is now overcharged, being your moonlighter simply did a gas n' go on you.

    If the coil is old, don't be surprised if pro recommends evap coil replacement. Everything sooner or later must pass a point of no return, and with neglected evap coils, this is a common occurence. The coil can become so impacted with dirt that cleaning it will not return it to like new performance. That, and older coils are subject to freon leaks and drain pan deterioration.

    • Electricity makes refrigeration happen.
    • Refrigeration makes the HVAC psychrometric process happen.
    • HVAC pyschrometrics is what makes indoor human comfort happen...IF the ducts AND the building envelope cooperate.


    A building is NOT beautiful unless it is also comfortable.

  4. #4
    Join Date
    Jul 2005
    Posts
    19
    My heat pump coil had the same problem with I first moved into my home. The previous owner operated the unit sans an air cleaner. All of the dust and crapola that stuck to the coils allowed moisture to accumulate and grow mold. That's the black stuff you see on the coils. It smells bad too!

    I was able to clean my coils without removing them. It was a pain in the butt I got it done with determination and lots of elbow grease. You will need a stiff brush (not metal) and lots of warm soapy water. Also make sure that your drain is flowing freely because when you start cleaning those coils you will need good drainage to the outside or it will overflow and become a HUGE mess.

    Go for it!

  5. #5
    Hey guys I did somemore troubleshooting and found a freon leak on my outside unit. My question now is...is it fixable and what will they need to do to fix it? The leak is in the smallest line(thinner than a pencil)it looks to be running to one of the three valves. I am not going to attempt fixing this myself.lol I just don't want a lazy A/C guy to come out and say I need a new system if the one I have can be repaired. The line looks like it was rubbing against something and it wore through so it is not just a pin hole. I don't know if the line can be soldered or if they are able to solder in a new line for me. I will send a pic here shortly.

  6. #6
    Hey guys I did somemore troubleshooting and found a freon leak on my outside unit. My question now is...is it fixable and what will they need to do to fix it? The leak is in the smallest line(thinner than a pencil)it looks to be running to one of the three valves. I am not going to attempt fixing this myself.lol I just don't want a lazy A/C guy to come out and say I need a new system if the one I have can be repaired. The line looks like it was rubbing against something and it wore through so it is not just a pin hole. I don't know if the line can be soldered or if they are able to solder in a new line for me. I will post a pic here shortly.

  7. #7
    Join Date
    Jul 2004
    Location
    Southern Alabama
    Posts
    448
    The hole in the line should be able to be repaired. No guarantees.

    You have done a wonderful job finding the leak. Your tenacity is to be commended.

    NOW get a licensed professional in there to get the hole fixed properly.

    Also, you might want to ask him about getting your unit on a routine maintance schedule.

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