What I'm Seeing Now


"It Leaked All Summer. Now It Has Stopped." Another HVAC Mystery!

One year inspections are fun because I ask if there are any things in particular the client wants me to look at.

Often I get a response like this:  "Until recently there was a puddle on the floor of the furnace room.  It leaked all summer.  Now it has stopped."

When I hear that I am pretty sure the leaking has to do with AC condensation, for some reason.  And now that the AC isn't operating the mysterious leaking has stopped.

But I go look anyway!

When I entered the furnace room and saw this I was not surprised.

Overhead is the main HVAC supply duct for the main level.

Off of this runs each of the individual, smaller duct tubes that service the various rooms of the main and basement levels.

The unit is to the left.

It is the horizontal duct in the center of the photo that interested me.

That is the main exhaust leaving the furnace, for heat and AC.

Notice the angle!

When things are running well the AC air coming out of the unit is around 45 - 50F.  That's pretty cold air!

It is so cold as compared to the air in the room that condensation will surely result.

Ideally the condensation is contained inside the unit, or directed there for discharge elsewhere.

In this case the angle of the duct is directing some of that condensation away from the unit, and toward that curved section of the duct.

It would sit there, except for one thing.

See the teensy hole?

That's in that "painted" joint!  It's also a low point!

That joint is painted with a latex duct product intended to seal small gaps in the metal duct work.

It"s pretty good stuff!  But not when there's a hole, or when a hole opens up!

Surely, all summer, that hole leaked, dripping water onto the floor of the room.

A lot of water?  Probably not.  But a puddle resulted every time the system ran for a while.

That they never noticed the dripping surprised me!  I asked, and they had not!

My recommendation:  when your unit is doing something odd during a particular season, there is probably a reason related to that season!  Maintenance requires a couple of things.  First, listen to your unit.  If it starts sounding differently call a professional.  Second, watch your unit operate.  If it does different things (like in this case water dripping from a hole that opened up) call a professional.  BUT IF YOU WANT A PROBLEM INVESTIGATED BY AN OBJECTIVE PROFESSIONAL - CALL A HOME INSPECTOR!  He might just be able to diagnose the problem!



Jay Markanich Real Estate Inspections, LLC  

Based in Bristow, serving all of Northern Virginia.

Office (703) 330-6388   Cell (703) 585-7560


Comment balloon 40 commentsJay Markanich • November 29 2013 03:55AM


This is funny.  It appears to be a case of the home owner ignoring the obvious.  Leaks when the unit is on.  Doesn't leak when the unit isn't on.


Posted by Lenn Harley, Real Estate Broker - Virginia & Maryland (Lenn Harley, Homefinders.com, MD & VA Homes and Real Estate) over 6 years ago

Good catch.  I'm also suprised that they didn't notice this.  All they had to do was look up.

Posted by Women of Westchester Working Together, Women helping Women get ahead (Women of Westchester Working Together) over 6 years ago

I was surprised too Lenn, except both of these are professionals, no children, and never home!  I pretty much knew what was going on during the phone call, but the inspection was more fun.

WOW Cuz - I know!  They looked up.  Or down.  Or all around.  Maybe their pants were falling down?

Sorry, I just went straight to fourth grade.

Posted by Jay Markanich, Home Inspector - servicing all Northern Virginia (Jay Markanich Real Estate Inspections, LLC) over 6 years ago

So you're telling me that when there's no hot air coming out of my floor registers every half hour or so, that the furnace isn't broken and fixing itself then breaking again? Wheew, that's good news I think, but I'm not sure.

Posted by Scott Seaton Jr. Bourbonnais Kankakee IL Home Inspector, The Home Inspector With a Heart! (SLS Home Inspections-Bradley Bourbonnais Kankakee Manteno) over 6 years ago

Jay is it normal for the duct to be at that angle where the water can collect? Plug the hole and problem solved.

Posted by Michael Setunsky, Your Commercial Real Estate Link to Northern VA over 6 years ago

Hi Jay,

I found this in a manufactured home with the same issues, The seam had seperated and was condensating on the exterior of the ducting causing the floor to warp.

The :Mastic: sealer used needs to be installed liberally. Not in a very thin amount. Good find.

Have a great day in Bristow my friend.

Best, Clint McKie

Posted by Clint Mckie, Desert Sun Home, Comm. Inspection 1-575-706-5586 (Desert Sun Home, commercial Inspections) over 6 years ago

Thank you for the post. I learned something new from the post and comments.

Posted by Gita Bantwal, REALTOR,ABR,CRS,SRES,GRI - Bucks County & Philadel (RE/MAX Centre Realtors) over 6 years ago

Self regulating and self fixing Scott!

Mike - ideally that duct should be level or angled toward the unit so condensation flows back into it.

Clint - for sure.  It's good stuff when used right.  They are not very liberal with it.

Gita - that I why I come to AR!  To learn!

Posted by Jay Markanich, Home Inspector - servicing all Northern Virginia (Jay Markanich Real Estate Inspections, LLC) over 6 years ago

If I lived next door to Lenn#1, I would check with her before I called you ....On this post subject, I had this and there are so many little things to check when servicing the these systems. I had a pro go over the whole thing and it is at optimum. Servicing is necessary too..good post

Posted by Richie Alan Naggar, agent & author (people first...then business Ran Right Realty ) over 6 years ago

Jay, even I might have caught that one, and I am no rocket scientist. I guess some people don't connect condensation with air conditioning?

Posted by Tom White, Franklin Homes Realty LLC, Franklin TN (Franklin Homes Realty LLC (615) 495-0752 or www.FranklinHomesRealty.com) over 6 years ago

LOL, people are little slow some times. If it leaks get it fioxes.


Posted by Than Maynard, Broker - Licensed to List & Sell - 405-990-8862 (Coldwell Banker Heart of Oklahoma) over 6 years ago

You are the Sherlock "Homes" on the AR blue and gold team.... love the CSI series that you one by one hunt and peck...on this is my house haunted or did someone drink a thirty pack fixing my house, building it? Before I came on the scene as a home seller? Got a set of keys to all the doors. Central air not so common in these parts.

Posted by Andrew Mooers | 207.532.6573, Northern Maine Real Estate-Aroostook County Broker (MOOERS REALTY) over 6 years ago

Let's see.... gravity. Things fall straight down. Oh, water on floor... look straight up, voila! A hole. I should be a home inspector! The one year warranty inspection is crucial, get that baby checked out before the builder is off the hook!!

Posted by Fred Hernden, CMI, Albuquerque area Master Inspector (Superior Home Inspections - Greater Albuquerque Area) over 6 years ago

I also am surprised the homeowner never noticed where the hole was especially with water sitting somewhere. Looks like a bad installation to me.

Posted by Bill Reddington, Destin Florida Real Estate (Re/max By The Sea) over 6 years ago

I would call Lenn too Richie.  An annual service contract isn't needed on this unit for another five years or so, but it should have been looked at when they installed it.  That duct is angled improperly.

Tom - obviously not.  I see humidifiers on all summer long!

Than - I guess they wanted to wait until their one year for me to identify what it is!

Andrew - this one wasn't too hard, but thanks!  As to ghosts, you should read this:


I do a lot of them Fred.  And I agree.

Posted by Jay Markanich, Home Inspector - servicing all Northern Virginia (Jay Markanich Real Estate Inspections, LLC) over 6 years ago

Bill - I think the hole must have opened up over time.  But don't know.  It may have started leaking from day one of the AC season.

Posted by Jay Markanich, Home Inspector - servicing all Northern Virginia (Jay Markanich Real Estate Inspections, LLC) over 6 years ago

That's the problem, people don't pay attention to units like these. It's good to know some basic knowledge of how they operate, and have a little common sense.

Posted by Suzanne Otto, Your Montgomery County PA home stager (Six Twenty Designs) over 6 years ago

They showed their common sense when they called me for a one-year warranty inspection Suzanne!

Posted by Jay Markanich, Home Inspector - servicing all Northern Virginia (Jay Markanich Real Estate Inspections, LLC) over 6 years ago

Jay, were you able to figure out what water was doing in the ductwork?

Posted by Charles Buell, Seattle Home Inspector (Charles Buell Inspections Inc.) over 6 years ago

I have seasonal issues sometimes as well. Like in my car leaking water on the garage. Duh

Posted by Karen Fiddler, Broker/Owner, Orange County & Lake Arrowhead, CA (949)510-2395 (Karen Parsons-Fiddler, Broker 949-510-2395) over 6 years ago

Summer leaks are such a nuisance. Cold water pipes in the basement, duct-work in the attic as well, and the list goes no. What ever the season, it needs to be checked out by a technician or the friendly neighborhood inspector.

Posted by Ed Silva, Central CT Real Estate Broker Serving all equally (RE/MAX Professionals, CT 203-206-0754 ) over 6 years ago
So they knew it leaked all season but never thought that they might want to have it looked at. Hate to see how many issues will mount up over the years that they'll ignore.
Posted by Aaron Hofmann, aka Mr. Smyrna Vinings (Atlanta Communities) over 6 years ago

People are funny sometimes.  If there is a problem in a specific season only, it's probably related to a seasonally used device.  In this case, voila!

Posted by Kat Palmiotti, The House Kat (406-270-3667, kat@thehousekat.com, Broker, Blackstone Realty Group - brokered by eXp Realty) over 6 years ago

Wow, it leaked all summer and they did nothing about it?  I hope they don't do the same thing with a gas leak!

Posted by Jim Patton, Realtor - Stanislaus ,Merced, San Joaquin Counties ( Aspire Home Real Estate 209-404-0816) over 6 years ago

I think it was condensation coming off the AC unit, and pooling at the edge of the duct Charlie.  But that hole is the low spot, so it was coming out there, conveniently.

Karen - it's a seasonal thing!

Ed - I think these folks must have been waiting for the one year inspection before deciding what to do.  Now it is probably the builder's issue.

Aaron - hopefully they don't let things slide after this one-year thing is up!

Kat - I think we figured this one out!

Jim - gas leaks usually take care of themselves, when a spark happens...

Posted by Jay Markanich, Home Inspector - servicing all Northern Virginia (Jay Markanich Real Estate Inspections, LLC) over 6 years ago

This is a very informative post.  Thanks for the tips aond waht to look for!

Posted by Joan Whitebook, Consumer Focused Real Estate Services (BHG The Masiello Group) over 6 years ago

I wasn't sure if the hole was an inspection point or a hole created by improper installation or maintenance. Great point about calling when the problem presents itself and not after it has quit!

Posted by Gerard Gilbers, Your Marketing Master (Higher Authority Markeing) over 6 years ago

Even with my bad eyes I think I would have seen that one.  Then again maybe not. 

Posted by James Dray, Exceptional Agents, Outstanding Results (Fathom Realty) over 6 years ago

Joan - one has to pay attention to the whole picture.

The hole was there Gerard.  I did not create it.  But calling while the problem is occurring might be the better course!

James - again, you have to see the whole picture!  And angles, holes, etc.

Posted by Jay Markanich, Home Inspector - servicing all Northern Virginia (Jay Markanich Real Estate Inspections, LLC) over 6 years ago

Interesting how we need to become sleuths to find the solutions - well done, Jay!

Posted by Dagny Eason, Fairfield County CT, CDPE Homes For Sale and Condo (Dagny's Real Estate) over 6 years ago

Its amazing how accurate your words are. That no matter how nice or how new there are likely things that could be found or improved upon or upgraded to mmake it better etc. in this case it was you discovering the culprit of the puddle but I now am considering should I get an inspection on my home I live in!?!?!?! Likely better to find out an problem before it becomes one thatn fixing something that broke!

Posted by David Shamansky, Creative, Aggressive & 560 FICO - OK, Colorado Mtg (US Mortgages - David Shamansky) over 6 years ago

Better sleuthing to find a problem than a wet banana nut bread Dags.  The horror...

David - that is a market I have tried to tap unsuccessfully for years!  Everything can maybe be improved!

Posted by Jay Markanich, Home Inspector - servicing all Northern Virginia (Jay Markanich Real Estate Inspections, LLC) over 6 years ago

I have weather related issues... like the tire losing are when the temperature outside changes quickly. HA! 

Posted by Joni Bailey, Your Huntsville / Lake Livingston Area REALTOR® (101 Main St. Realty) over 6 years ago

This is exactly why I STRONGLY suggest my clients ALWAYS get a home inspection included in the purchase contract so they can find out about these things BEFORE they close the deal.

If a seller has ignored or failed to mention something like this, how many other surprises are they withholding from your buyers ?

Posted by DEANNA EARLY - - ( NMLS # 268590 ), Highest Ranked Mortgage Loan Originator Virginia (American National Bank & Trust) over 6 years ago

Check your stem Joni!  Um, I mean, your tire stem.

I think this may have happened during the year Deanna, but they did not get a final home inspection on the house at their final walk through. I am sure I would have caught the angle of that duct.

Posted by Jay Markanich, Home Inspector - servicing all Northern Virginia (Jay Markanich Real Estate Inspections, LLC) over 6 years ago

It's funny how some people and agents don't have much of a clue about condensation, hvac, and other basic home maintenance issues, and how things work. On a house I sold back in summer, the agent and new buyer called and texted a day or so after closing. They were panicing because water was dripping out of the downspout onto the deck, and it hadn't rained in several days. They did have a home inspection, but they were never informed that the unit was mounted in attic and condesation line was routed over into the gutter. I told them to just call their inspector, or to go up in attic so they could see where water was originating. They did, and they we're fine afterwards.

Posted by Jeff Pearl, Full Service Full Time Realtor (RE/MAX Distinctive / LIC in VA) over 6 years ago

 Good morning, Jay. I think that you are lucky that they even sealed the ductwork with latex. Most of the time, they use tape.

Posted by TeamCHI - Complete Home Inspections, Inc., Home Inspectons - Nashville, TN area - 615.661.029 (Complete Home Inspections, Inc.) over 6 years ago

That is one of those home ownership life lessons that are learned one at a time Jeff.  I'm not a fan of condensates that drip into the gutter because it isn't noticeable when it isn't working well.  How often do you go investigate your downspouts when the weather is dry?

Michael - that is pretty common here now, with new construction.  It's sticky stuff!  Tape has been used for a long time, and, as we know, comes apart readily.

Posted by Jay Markanich, Home Inspector - servicing all Northern Virginia (Jay Markanich Real Estate Inspections, LLC) over 6 years ago

Jay, Maintenance? What the heck is that. I do not know about you but when I find a system that has been maintained I am almost shocked.

Posted by Donald Hester, NCW Home Inspections, LLC (NCW Home Inspections, LLC) over 6 years ago

When I find one, Don, I point it out with fervor to my clients!

Posted by Jay Markanich, Home Inspector - servicing all Northern Virginia (Jay Markanich Real Estate Inspections, LLC) over 6 years ago

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