[ArizonaArty]

About the unit: It is a carrier split unit. Electric. Provides heating and cooling. Sorry, I don't know much more about it than that. This particular unit cools the top level of my house, which is actually 1 large room about 800 sq ft.

I've tried to resolve the issues and have come up against a few things that needed to be taken care of but its still not working as it should.

Originally, the airflow coming out of the vents was weak and not cold.

I have an electric air cleaner so I took out that filter and cleaned it, along with the main part which I believe does the zapping (sorry, don't know its name).

The blower motor spins fine, and when I have the side panel off the airflow from the outlet vents is strong which lead me to believe it was a blockage between the inlet and blower motor. I ran the system without the electronic air filter and the airflow still wasn't strong or cold which left the evaporator coil.

I used a can of this stuff, which brought some crap to the surface. I sprayed it on both sides. I used a soft brush to brush that crap away.

http://www.lowes.com/pd_241324-13...il+cleaner

I then purchased this and used about half of it so far:
http://www.amazon.com/Nu-Calgon-4...B000R7ZS08

And then, for good measure, I took my steamer and steamed it (although I didn't do this for very long). The steam seemed to go through the coils without a problem.

I ran the system. The airflow is much better, but I think it should be better than it is. The temp isn't dropping below 90, usually hovering around 93. I used a infrared thermometer and after the unit has been running the temp difference between the inlet and outlet is only 3 degrees. I believe that should be around 20.

So, I opened up the system, and there is some icing along some of the lines. Its not along the main coil units like I have seen on some images/videos.



I also took a picture of the coils. Its hard to get our head in there, and from the picture it looks like it could still be a bit dirty, but I'm wondering if that would be enough to cause all of these problems? I thought I had cleaned them up but looking at the pictures I'm guessing not. I noticed a few bugs in the picture, I'm wondering what's going on in the parts I can't see. Would using a compressor to blow from the bottom up be a good idea?

Top coil:


Bottom of the coil:




After taking the picture of the top of the coils, it looks like its not as clean as I thought it was. But can that still be the sole cause to this problem? I was thinking of getting another couple of cans of the Web coil cleaner to give it another nuking. Although I may try some hot water and dish detergent first.

Is this a Freon issue? I had the outside condenser unit replaced about 2-3 years ago (original was stolen).

Does anyone have any suggestions?

Thanks in advance.

[hkstroud]

I am not an air condition tech.

But,

I have an electric air cleaner so I took out that filter and cleaned it,

Is there another regular filter in the system?

Hard to tell but the right hand side of your picture of the cleaned coil doesn't look very clean.

I then purchased this and used about half of it so far:
http://www.amazon.com/Nu-Calgon-4...B000R7ZS08

If you properly mixed with water, that means you sprayed about 1 1/2 gal of cleaner. That amount should have cleaned the coils. However you can always do it again.

You an also use a brush, a toilet bowl brush would probably work fairly well.
You can also use compressed air, blowing in the direction opposite the air flow.

In your last picture it looks like coil is beginning to frost up.

Turn thermostat to fan only and see what air flow you have. If coil and filters are clean you should have good air flow. Won't be the same as when you had the unit open however.

If you have good air flow when the unit first starts which later decreases or if you have good air flow when thermostat is turned to fan only but not in the cool mode, you probably have a low refrigerant which is causing coil to ice up.

[talaniman]

I agree you may have low refrigerant, and a leak some where(?). I recommend you have your refrigerant checked and recharged if necessary as a starting point. Also check your house filter where your heating unit is located (usually in the attic, above your drip pan, next to ) for any evidence of refrigerant leaking/freeze up of those EVAPORATOR coils also, as a dirty filter and/or frozen coils will completely restrict air flow to the house vents.

Turn the unit completely OFF before you inspect the whole system, and then allow thawing (hour, or two), before checking refrigerant level, and adding. Furnace filters are throwaways and should be changed regularly, never cleaned, and are pretty cheap. When was the last time yours was changed? Behind that filter are these coil

Water Coils - Standard Circuiting Diagrams - Full Circuit Coils - USA

Review this for insights into your system

What is a Split System Air Conditioner? (with pictures)

The parts of the system include a compressor, fan, condenser coil, evaporator coil and refrigerant. The condenser coil is installed outside and connects to the evaporator coil or coils inside different rooms in the house. The evaporator coils are individually controlled, allowing the home owners to set each room to a different temperature. Both condenser and evaporator coils are connected to the refrigerant lines.

Just follow your duct work and you will be lead right to it. Let me know what you find.

[ma0641]

Icing of coils is typically due to these reasons: 1-Low Freon, 2-blocked air flow through a dirty coil, 3-air handler flow is low due to slipping belt(old models), loose cage or failing motor. Look for a compacted filter too. I was just helping a neighbor and we found that an old filter had disintegrated and the pleating was sucked into the fan plenum.

[ArizonaArty]

Answering some of the questions...

hkstroud:
There is no regular air filter. Its not that I haven't put a filter in, its just the fixture is not designed to take one. I will probably have that corrected this winter for 2 of my 3 units. There is what appears to be an aluminum filter right before the electronic air cleaner.

I did use a brush, a soft dust pan bush. A soft brush was recommended by a YouTube video/website to avoid damaging the fins.

In that last picture, that is 2 copper tubing of some kind that is freezing over, the coils themselves (assuming I am referring to the right part, the main grid part you see) wasn't frozen over, at least not that I can tell. If it is freezing, its on the inner parts because I can't see it although I am running the system right now and will let it run for longer than normal and will inspect the coils.

talaniman:
Is checking/adding freon something I should be doing? Isn't that something I should call someone in to do?

There isn't a standard house filter, but one of those metal mesh ones which is part of the electronic cleaning system. I've pulled that out and cleaned it, along with the other part of the electronic cleaning system that slides out.

I'm sorry, I thought I had included more information in my original post. It's a split system. The evaporator coils are not A shaped like many I have seen in pictures, just the one part at an angle (see pictures above).

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Today, I got another can of the web coil cleaner and a small air compressor (135PSI). I blew out the coils in the opposite direction of the air flow. A little dust, but nothing that would be the cause of the problem. I then sprayed the web coil cleaner, sealed up the unit, and let it run so the condensation would clean the spray away.

I also hanged some tissue paper attached to paper clips to the vents to see the airflow. After 25 or so minutes, the airflow seemed consistent but was only 3 degrees cooler than the inlet. I do feel it could be stronger, but it is a high ceiling and i do feel it when i am standing in the right spot so thats something.



So, at this point, would be it fair to think it's the freon?

[talaniman]

It would well be worth it to call a guy out for the freon check, and ask him to show you your complete system including your EVAPORATOR coils.

[ArizonaArty]

It would well be worth it to call a guy out for the freon check, and ask him to show you your complete system including your EVAPORATOR coils.

I know where my evaporator coils are, I provided pictures of that.

[ArizonaArty]

Here is my understanding of my unit.

[ArizonaArty]

Oh, and I just noticed something else. I thought it might just be a noise it was suppose to make and I was just noticing it because I was up close and personal with the unit, but I just checked my other units and they don't make this noise.

When the AC is running, it makes a sound that reminds me of an old refrigerator, like there is a metal can rattling around. I'm not sure if I'm describing it right but I'm guessing someone knows what I mean :)

It doesn't make the noise when its just the fan running.

[ArizonaArty]

I just ran the AC for about 2 1/2 hours.

When I took off the panel to look at the evaporator coil, it looked like it did in the previous picture. I'm posting the old picture here...




The freezing is just along those thin copper lines. I blew air through the fins and the air went through OK. Air flow after 2 hours is just fine.

Looking at other pictures online of frozen systems, I noticed the curved copper parts at the end are frozen in some pictures like this...



Is the fact that mine is not doing that help identify the problem? Am I right in thinking I need Freon?

And just as a reminder, that second picture is NOT my system.

Thanks :)

[talaniman]

Have the freon levels checked first, and go from there. It should be done as a matter of routine every year anyway.

talaniman:
Is checking/adding freon something I should be doing? Isn't that something I should call someone in to do?

Strongly advisable since they have the gauges and freon your unit uses (and know how), and can help you pin down any other problems and concerns you may have. No doubt you will gain even more understanding and insights from an experienced certified guy and can ask real time questions in person.

How old is your unit?