Ceiling Damage Ductwork Condensation/Water (not In Attic)... - HVAC - DIY Chatroom Home Improvement Forum


Go Back   DIY Chatroom Home Improvement Forum > Home Improvement > HVAC

CLICK HERE AND JOIN OUR COMMUNITY TODAY...IT'S FREE!

Reply
 
Thread Tools Display Modes
Old 07-02-2013, 09:14 AM   #1
Newbie
 
Join Date: Jul 2013
Posts: 6
Rewards Points: 10
Question

Ceiling damage Ductwork Condensation/Water (not in attic)...


I just had to cut a small piece of my kitchen ceiling out because of water damage. Once I put my head there and took a look I noticed the ductwork and flex piping in the ceiling had a lot of condensation and water was dripping on to the drywall ceiling. There is condensation and water dripping in other areas besides the part that I cut out. This issue is in the ceiling of my 3-level 20-year old townhouse between the 2nd and 3rd floor. The ductwork, as far as I can see, is not insulated (guessing because above and below are 'conditioned' space. Right above the issue area is a bedroom. I did some searching and I only really found this issue discussed mostly associated with attics. I have a home warranty and opened up a work order on the A/C as I think it has to be related (I'm a total newbie). I also noticed some condensation on the cold side of the system that's located in a utility closet on the 1st floor of the townhouse.

Does anyone have any thoughts on what could be causing this problem?

Advertisement

rosadod is offline   Reply With Quote
Old 07-02-2013, 02:02 PM   #2
Member
 
Join Date: Oct 2012
Posts: 282
Rewards Points: 266
Default

Ceiling damage Ductwork Condensation/Water (not in attic)...


High humidity levels in the air meeting the cold surfaces of the duct work. The surfaces that are condensing are at or below dew point.

Is this an indication of a problem with the system? Maybe.

I am "more" inclined to think it's more than likely an issue with how you're running your system.

I see this more often (with duct work that is within the conditioned space) when the homeowner runs the system only when they are home to save energy, allowing the home to warm up and the humidity to increase during the off times. The other situation is when the AC is turned off at night and the windows opened up because it's cooler outside. If the humidity level is high outside all this humidity comes into the home waiting for the next time the AC runs.

There are situations where problems with the AC system could cause this. Biggest one would be dirty air filters or blower wheel which reduce the air flow and can greatly reduce the air temperature that is being sent into the duct work. This condition can cause "sweating" for hours on end.

Is duct work normally insulated in a residential conditioned space? No, it's actually very rare........ 25 years and I've never been asked, told or volunteered to do it even on very high end homes with the plans and the job supervised by an engineer.

Advertisement

old_squid is offline   Reply With Quote
Old 07-02-2013, 02:20 PM   #3
Member
 
FClef's Avatar
 
Join Date: May 2013
Location: Pennsylvania
Posts: 216
Rewards Points: 156
Default

Ceiling damage Ductwork Condensation/Water (not in attic)...


It could either be the way you are operating the unit or you might have a blocked condensate drain. Like Squid said, when ducts are in a conditioned space it is rare that they are insulated.

Just a silly question but is there any plumbing in the area that may have started leaking? The reason I asked is because if ducts are going to sweat they will more than likely always sweat and there would have been indications of this problem before this time.
FClef is offline   Reply With Quote
Old 07-02-2013, 03:38 PM   #4
Newbie
 
Join Date: Jul 2013
Posts: 6
Rewards Points: 10
Default

Ceiling damage Ductwork Condensation/Water (not in attic)...


Thanks for the inputs... This is actually a rental property I have about a mile from my current house. The air filter was replaced about 1 month ago. I'm not sure if the blower wheel is dirty or not. I did check the condensate drain and it's clear. I'll have to ask my tenant about how she runs the system. The HVAC folks will check it out Friday morning.
rosadod is offline   Reply With Quote
Old 07-02-2013, 03:56 PM   #5
Member
 
Join Date: Sep 2012
Posts: 2,197
Rewards Points: 1,650
Default

Ceiling damage Ductwork Condensation/Water (not in attic)...


If the tenant isn't paying the electric bill the stat may be set at 68 or some other unreasonable number below dewpoint.
SeniorSitizen is online now   Reply With Quote
Old 07-02-2013, 04:09 PM   #6
Newbie
 
Join Date: Jul 2013
Posts: 6
Rewards Points: 10
Default

Ceiling damage Ductwork Condensation/Water (not in attic)...


The tenant does pay the electric bill. When I was there yesterday she had the temp set to 71. Can you explain your dew point reference? I'm trying to google it not too.
rosadod is offline   Reply With Quote
Old 07-02-2013, 04:36 PM   #7
Member
 
Join Date: Sep 2012
Posts: 2,197
Rewards Points: 1,650
Default

Ceiling damage Ductwork Condensation/Water (not in attic)...


Quote:
Originally Posted by rosadod View Post
The tenant does pay the electric bill. When I was there yesterday she had the temp set to 71. Can you explain your dew point reference? I'm trying to google it not too.
If the duct is colder than dew point temperature of the air that surrounds it there will be condensation. Example: a cold drink glass.

A dew point temperature reading doesn't always indicate a problem at the time it is checked being dew point temperature is subject to change early morning to afternoon, hour by hour and even minute by minute in rare instances. The HVAC contractor that will be checking your equipment should know all this and can hopefully solve the destructive wet problem.
SeniorSitizen is online now   Reply With Quote
Old 07-02-2013, 05:14 PM   #8
Newbie
 
Join Date: Jul 2013
Posts: 6
Rewards Points: 10
Default

Ceiling damage Ductwork Condensation/Water (not in attic)...


Ok... Thanks! I know the stats inside the house would be different, but, for example, today the temp is 76, 95% RH and 75 dew point. So, using your example and the house that she keeps at 71, a glass of water @71 degrees outside today with the dew point at 75 will produce condensation. Hopefully the contractor will have all the meters needed to figure out what is causing the problem. I will say that even though the temp in the house was at 71 when I was there, I was sweating a good amount cutting the the small piece of ceiling out and the tenant did mention that she was thinking about getting a dehumidifier. Don't mean to get ahead of myself, but if this is the problem, is the solution a dehumidifier? Or how should I have the tenant modify how they run the system?

BTW, FClef, there is no pluming in the area that I could see.
rosadod is offline   Reply With Quote
Old 07-02-2013, 05:55 PM   #9
Member
 
Join Date: Sep 2012
Posts: 2,197
Rewards Points: 1,650
Default

Ceiling damage Ductwork Condensation/Water (not in attic)...


For a given air mass, as the temperature is lowered the RH increases and eventually a point is reached where the air feels clammy. You sweating abnormally while cutting the ceiling is a good example. Everyone seems to have a preference as to temperature and I personally would try increasing the thermostat setting to the 75 - 76 range and add ceiling fans before going the dehumidifier route.
SeniorSitizen is online now   Reply With Quote
Old 07-02-2013, 09:21 PM   #10
An old Tradesmen
 
Join Date: Oct 2008
Location: PA
Posts: 26,438
Rewards Points: 4,522
Default

Ceiling damage Ductwork Condensation/Water (not in attic)...


Run the blower, then stick your head and hand up in the hole and check for air leaks in your duct work.

Also a good chance that the space between the ceiling and second floor has outdoor air infiltrating it.

Increasing the indoor temp, won't help to prevent the duct from sweating.
__________________
When posting in certain forums, knowing your location will help others give better feedback/advice/solutions to your questions.
beenthere is online now   Reply With Quote
Old 07-03-2013, 05:55 AM   #11
Newbie
 
Join Date: Jul 2013
Posts: 6
Rewards Points: 10
Default

Ceiling damage Ductwork Condensation/Water (not in attic)...


Quote:
Originally Posted by beenthere View Post
Run the blower, then stick your head and hand up in the hole and check for air leaks in your duct work.

Also a good chance that the space between the ceiling and second floor has outdoor air infiltrating it.

Increasing the indoor temp, won't help to prevent the duct from sweating.
Ok, but will I really be able to find a possible air leak with only access to this small area? What is the best way to pinpoint the leak myself? Also, how could I determine if and how outdoor air may be infiltrating the area?
rosadod is offline   Reply With Quote
Old 07-03-2013, 06:03 AM   #12
An old Tradesmen
 
Join Date: Oct 2008
Location: PA
Posts: 26,438
Rewards Points: 4,522
Default

Ceiling damage Ductwork Condensation/Water (not in attic)...


The area that the ceiling came down, would be the area with the worse duct leakage. Should be able to feel air movement. Can use an incense stick near the seams if you don't see any holes in duct or feel any air moving.

Band board is where it would probably be leaking in at. Usually can't see all the areas. A blower door and IR camera would be needed to find all of the areas where air is leaking in.

Check for duct leaks first, go from there.
__________________
When posting in certain forums, knowing your location will help others give better feedback/advice/solutions to your questions.
beenthere is online now   Reply With Quote
Old 07-03-2013, 06:25 AM   #13
Newbie
 
Join Date: Jul 2013
Posts: 6
Rewards Points: 10
Default

Ceiling damage Ductwork Condensation/Water (not in attic)...


Beenthere, Thanks! Clueless question... Is there band board between floors on every level of the house? Hopefully the tech will have all the equipment needed to check for leaks on Friday.
rosadod is offline   Reply With Quote
Old 07-03-2013, 06:49 AM   #14
Member
 
Join Date: Sep 2012
Posts: 2,197
Rewards Points: 1,650
Default

Ceiling damage Ductwork Condensation/Water (not in attic)...


Quote:
Originally Posted by beenthere View Post

Increasing the indoor temp, won't help to prevent the duct from sweating.
I respectfully disagree. Increasing the air temperature 4 increases duct temperature via return air therefore decreasing the chances of reaching dew point.
SeniorSitizen is online now   Reply With Quote
Old 07-03-2013, 04:48 PM   #15
An old Tradesmen
 
Join Date: Oct 2008
Location: PA
Posts: 26,438
Rewards Points: 4,522
Default

Ceiling damage Ductwork Condensation/Water (not in attic)...


Quote:
Originally Posted by rosadod View Post
Beenthere, Thanks! Clueless question... Is there band board between floors on every level of the house? Hopefully the tech will have all the equipment needed to check for leaks on Friday.
Yes, there should be a band board on every floor.

Advertisement

__________________
When posting in certain forums, knowing your location will help others give better feedback/advice/solutions to your questions.
beenthere is online now   Reply With Quote
Reply


Thread Tools
Display Modes

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


Similar Threads
Thread Thread Starter Forum Replies Last Post
Question: BNC cables through attic (studs to wall, or ceiling drywall?) eatmyturf Electrical 4 04-05-2013 11:25 PM
Ideas for retrofitting baffles/insulation in vaulted ceiling of built out attic room rachelsue20 Insulation 5 04-28-2012 08:49 PM
Water Damage: Repairing Ceiling Drywall Defects at Seams? Lovegasoline Drywall & Plaster 5 04-24-2012 07:57 AM
Advice for installing ceiling fan Ceiling Fan Man Electrical 5 06-02-2009 05:18 PM




Top of Page | View New Posts