Through the wall A/C vent/sleeve issue!

Reply

  #1  
Old 08-30-17, 01:40 PM
T
Member
Thread Starter
Join Date: Aug 2017
Location: United States
Posts: 2
Received 0 Votes on 0 Posts
Through the wall A/C vent/sleeve issue!

Hey DIY Forum!

First post here, and probably not the last! I just moved into a condo that had an old broken AC unit. I bought a new LG Through the wall AC to replace it:
Air Conditioners | Wall Air Conditioner | LG Through the Wall Air Conditioner LT1237HNR- 11,500 BTU Cool 11,200 BTU Heat 230V | 653532 - GlobalIndustrial.com

When I took out the old AC, I noticed that the sleeve is much deeper than the actual unit. The same went for this new LG unit.

After replacing the old unit, I now have the new LG unit flush with the interior wall, but there is about 9 inches - 1 foot of a gap behind the unit before the exit of the sleeve to the outside world. This new AC unit only intakes/vents through the back, so I don't forsee problem with it being in the sleeve, but I believe I have an airflow problem.

The cooling power of this 11,500 BTU unit is lackluster and I don't want to be paying a steep electricity bill for a DIY installation problem!

P.S. The sleeve is so long because it goes through a small exterior storage closet before exiting to the patio. Unless I completely relocate the unit (Making another hole in the wall and closing up the existing hole), the sleeve will have to remain this undesirable length.

Thanks in advance for any advice on this issue!
 
Sponsored Links
  #2  
Old 08-30-17, 05:55 PM
PJmax's Avatar
Group Moderator
Join Date: Oct 2012
Location: Northern NJ - USA
Posts: 59,840
Received 1,202 Votes on 1,112 Posts
Welcome to the forums.

Did you also get a sleeve for the new unit ? If you did do the air slots in the side match up or are they close. Most thru the walls units draw air in thru the sides and exhaust out the back, An extended length sleeve is not going to give you the best performance.
 
  #3  
Old 08-31-17, 04:31 AM
GregH's Avatar
Super Moderator
Join Date: Jan 2001
Location: Manitoba
Posts: 10,145
Received 38 Votes on 36 Posts
It is likely that the excess depth of the sleeve is causing leaving warm air to be mixed with cooler incoming air.
This will cause the ac to overheat causing poor performance and a much shorter life.

How deep walls are dealt with when installing PTAC units like what are commonly found in hotels is that sleeve extensions can be purchased to allow an increase in wall depth.
These sleeve extensions have a barrier to keep the intake and exhaust separate.

There is a potential problem with adapting this solution to your ac unit because the condenser fan may not be designed with enough capacity to make this work for you.
Check with the maker of your unit to see if this is available for what you have.
 
  #4  
Old 09-08-17, 03:46 AM
T
Member
Thread Starter
Join Date: Aug 2017
Location: United States
Posts: 2
Received 0 Votes on 0 Posts
Cool

Thanks for the reply guys!

I did not purchase a sleeve with this unit, as there was already a metal casing in the hole from the old AC. This model of LG Air conditioner (link in previous post) does not have vents on the sides, so I think I avoided that problem!

I have attached pictures of what I'm working with. A you can see, the intake is on the back with a very small portion of air intake wrapping around the back corner.

Interested point about the barriers within the sleeve. I thought about bringing the back of the unit flush with the outdoor vent and building my own barriers to go inside the sleeve to then funnel the cool air into my condo. Not sure if that makes sense.

If I were to use the existing sleeve and find DIY materials to create a seal/barriers, what materials would you (forum compendium of knowledge) recommend? I was thinking to use the provided foam for the seal and then styrofoam/cardboard to create that funnel of cold air into the living room.

I invite any red flags you see with this method, as I want my AC to live as long as possible!
 
Attached Images    
  #5  
Old 09-08-17, 01:24 PM
PJmax's Avatar
Group Moderator
Join Date: Oct 2012
Location: Northern NJ - USA
Posts: 59,840
Received 1,202 Votes on 1,112 Posts
It looks like the unit could be slid in..... a little closer to inside the house.

The cooling power of this 11,500 BTU unit is lackluster
I can see why. You also need to add a divider inside the sleeve to keep the incoming cool air separated from the hot discharge air. Could be a 1/4" plywood or sheet metal. Cardboard would be a last resort.
 
Attached Images  
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: