[sayluv]

Hi-

During the winter we intermittently hear a dripping/pinging sound in the wall. For a long time I thought it was the pipes but I have searched around the web and read posts about others who have the same sound and they believe it is the HVAC vent (either humidity or more common answer is just the metal expanding and contracting).

I heard the clicking the other morning at 6AM. We keep the house at 67 degrees at night. After a minute or two of putting the heat up to 70 the noise stopped. This makes me think it is not humidity but maybe not. Currently we have the humidity in the AC system set to about 20%--15% is the lowest.

Our place was built 2011 (Chicago).


1) Does anyone have an idea what this may be?
2) If you do know what it may be, how would be fix it? Do we need to punch a hole in the wall? That does sound like a good idea.

Thanks, sl

 

[Gymschu]

Heating systems cause expansion and contraction as you know. Depending on the type of system you have, metal parts or copper pipes (heated water system) expand against framing in the home and can cause pinging/dripping sounds. I know copper pipes can move as much as a 1/4 to 1/2 inch when heated water moves through them. A recent episode of This Old House showed Richard Trethewey shortening some copper pipes that were expanding against some wood trim in a house causing lots of noise.

 

[sayluv]

Thanks. I think I saw that episode =). I just wish I could fix this problem but I don't think that is going to happen.

 

[Chris130]

I can relate... When the is quiet enough and the furnace is running, I can occasionally hear a very soft drip. Or something that sure as heck sounded like a drip... At first, I would've bet everything I own that it was a drip - it was that convincing.

Fortunately, my house is small, so it wasn't too difficult to finally "find" it - I just had to be in the right place at the right time... The sounds is on one of my supply-side air ducts from the furnace - as it goes up into the first floor (from the the basement), there must be a fitting right in that area the vent expansion/contraction is causing that soft drip-sounding pop/ping.

If I simply reach up and press (even just very softly) up on that duct where it goes up into the floor, the sounds stops.

Now that I finally know what it is, I can definitely live with it - it's fortunately not an annoying, pervasive, or loud sound... I'm just glad to know what it is.

Sounds alone can definitely be deceiving, that's for sure!

Cheers, Chris

 

[sayluv]

Glad you found your issue Chris. I think the nearest vent is about 4-5 feet from the noise. Maybe I will try and stick my iphone up there and take a look or try and slide a weight down there to see if it helps.