Evaporator Coil Freezing/ Leaking Water

Reply

  #1  
Old 06-08-14, 02:09 PM
S
Member
Thread Starter
Join Date: Jun 2014
Posts: 5
Received 0 Votes on 0 Posts
Evaporator Coil Freezing/ Leaking Water

Hi all, first time posting on the website.

Our AC works great when it is first turned on, blows strong cold air. After running for quite some time (usually over 2 hours straight), the air pressure is reduced. I checked our evaporator coil today and saw that the reduction in airflow is due to the coil freezing. When this happens, i have been turning off the compressor and just allowing the fan to run to try to melt the ice buildup.

However, when i turn on the fan, usually after 2 minutes or so, water starts to leak out one corner of the evaporator coil box. I checked the drain and it is clear of any blockage. However, the coil box seems to not be completely level (tilting just slightly away from the drain). I am wondering if the box not being completely level would cause water to pool in the back? Why would it only leak when the fan is on?

I also do not think that being level is the reason for the freezing... We had a tech come a month or so ago for our spring tune-up and said our refrigerant level was good. Any ideas or suggestions would be much appreciated!

Thank you!
 
Sponsored Links
  #2  
Old 06-08-14, 02:19 PM
PJmax's Avatar
Group Moderator
Join Date: Oct 2012
Location: Northern NJ - USA
Posts: 57,075
Received 836 Votes on 783 Posts
Welcome to the forums.

The level issue has nothing to do with your coil icing up.

There are two reasons for the evaporator coil to ice up. One is not enough airflow and the other is low on refrigerant.

When the coil ices up and then you turn the blower off for a while and then back on... the coil unthaws and there is a lot more extra water to get rid of. Try re-leveling the box. It should lean towards the drain....not away.
 
  #3  
Old 06-08-14, 03:36 PM
S
Member
Thread Starter
Join Date: Jun 2014
Posts: 5
Received 0 Votes on 0 Posts
Thank you for your quick response! I am hoping that it is not due to low refrigerant as we just had the system inspected about a month ago and the tech said the levels were OK.

We just bought the house in mid February and the freezing seems to have been an issue ever since we started using the AC. When you say airflow, is it possible that the filter in the machine is not letting enough air pass through quickly enough, and that is causing it to freeze? Would a new, different filter possibly help?

Thanks again for your help.
 
  #4  
Old 06-08-14, 04:12 PM
user 10's Avatar
Member
Join Date: Mar 2004
Location: NA
Posts: 2,043
Received 39 Votes on 33 Posts
Allergen filters cut airflow sinificantly.
 
  #5  
Old 06-09-14, 09:42 AM
S
Member
Thread Starter
Join Date: Jun 2014
Posts: 5
Received 0 Votes on 0 Posts
Another Note:

When I run the ac and then switch to fan only, I can see a decent amount of water running through the drain pipe (I can see it through the cleanout hole). When I switch the system back to AC, the amount of water is reduced noticeably until there is next to no water draining within 3-5 minutes. Is this unusual? Is it because the water is freezing instead of draining like it should?

I replaced the filter last night. Old filter was pretty dirty, but not terrible. We have a Aprilaire 2400 16" x 27" x 6" media filter. I am wondering if this is cutting the airflow...
 
  #6  
Old 06-09-14, 04:40 PM
Houston204's Avatar
Forum Topic Moderator
Join Date: Oct 2009
Location: Texas
Posts: 7,426
Received 17 Votes on 14 Posts
That 6 inch air filter is probably not the problem unless you are also using a restrictive air filter at the intake grill.

Was the unit icing up before it was serviced?

If not, spray some soapy water on the service ports outside.
 
  #7  
Old 06-19-14, 10:05 AM
S
Member
Thread Starter
Join Date: Jun 2014
Posts: 5
Received 0 Votes on 0 Posts
We bought the house in February and had not been running the AC much before we had the spring tune-up, so I am not positive, but I believe it was still happening before the service.

We had a tech come out today and told us that we were about 2 pounds low on refrigerant, so he added it. We will see if this is what was causing it... Would adding 2 pounds make that big of a difference and keep it from freezing?
 
  #8  
Old 06-19-14, 10:20 AM
PJmax's Avatar
Group Moderator
Join Date: Oct 2012
Location: Northern NJ - USA
Posts: 57,075
Received 836 Votes on 783 Posts
Would adding 2 pounds make that big of a difference and keep it from freezing?
Yes.... it could defintely cause that problem.
 
  #9  
Old 06-19-14, 12:12 PM
S
Member
Thread Starter
Join Date: Jun 2014
Posts: 5
Received 0 Votes on 0 Posts
Thanks for your response! I do have one more question (this is our first home, so my learning curve on HVAC has been pretty steep...)

Will the added refrigerant make the air any colder, or will it just keep the system from freezing up? Please pardon my lack of general HVAC knowledge...

Thanks!
 
  #10  
Old 06-19-14, 01:10 PM
T
Member
Join Date: Jul 2008
Location: Kansas
Posts: 317
Received 0 Votes on 0 Posts
If properly charged it will keep it from freezing up. A good tech would have looked to see why it needed 2 lbs. He will be back. It's called gas and go.
 
Reply
Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Thread Tools
Search this Thread
 
Ask a Question
Question Title:
Description:
Your question will be posted in: