duct noise driving me crazy

[Buzzy]

What's a guy to do?

It is the expansion/contraction of the ducts. Not the "tick" of the EAC.

It ticks every 3 or 5 seconds when the furnace first starts up and continues for a number of minutes. Then ticks again when the furnace shuts off for 10 minutes or so. Wakes me up at night!

Any ideas on how to stop it?

Thanks.

[firecontrol]

start with figuring out exactly where the noise is coming from and then call a contractor out to fix the noisy spots. that way you won't have to pay them to sit there and figure it out which can sometimes take hours on the clock.

[Irishmist]

more information would help.

Is this a new install?

did this problem just start?

How long has it been happening?

usually there is a process of 'cross-breaking' the ductwork as it is fabricated that 'stiffens' the ductwork and helps to minimize the 'ticking' from the ductwork.

I must say that the 'ticking' associated with the duct usually only happens when the blower comes on and goes off, as the duct is put under and released from pressure.

If this happens within seconds of the start up of the furnace, then it may be expansion and contraction.

Have a professional take a look, and DON'T tell him what YOU think it is. After all, you are paying for HIS expertise. He may see something you missed, and you can always share your thoughts with him after he has had a chance to inspect the system.

all the best, Irish

[Buzzy]

Thanks Irish and firecontrol.

As for more information:

The furnace is a new install. Hi eff. 2 stage variable speed. This furnace replaced a 25 year old Lennox. The new furnace itself is very nice and quiet. You cannot even hear it run in first stage and it keeps the temp very comfortable.

The duct work is old / existing.

This is our second winter in this house. The ticking did occur last year but was not as bothersome. But that may be because the old furnace operated differently than the new.

My thermostat is set to Fan - On (Is that the best practice?)

In the morning (after setting it back at night) is the only time the furnace really goes into the second stage. The ticking seems to stop then.

The ticking starts within a few seconds of fire up and lasts approx. 15 minutes then stops then starts ticking again when cycle ends for 10 - 15 min.

Does that give you any clues?

Thanks. And I have to say it's really great of all you Pro Members to take the time you do and avail your knowledge and expertise to us lay-folk. It is greatly appreciated.

[bertqc]

A recording of the sound could help :)
just a joke..

Could be as simple as a noisy relay..

[air2spare]

heat exchanger expanding on heat startup and contracting on heat off cool down? dont know, need more info.

dont run stat with fan "on" , especially with the variable speed, does you no benefit and uses more electricity

[Buzzy]

Thanks Air2spare. I wondered about that. The motor is a DC current which I understand is much cheaper to run. I put the t-stat on auto now.

Still ticks like before...

[air2spare]

the blower wheel may have a wire-tie or something to the effect that makes a ticking sound at low speeds, kinda like having something in the spokes of a bicycle wheel...dont know...get up there and spend some time with it

good luck

[skippedover]

dont run stat with fan "on" , especially with the variable speed, does you no benefit and uses more electricity

Not particularly good advice. Generally running a variable speed product with the fan in the 'on' condition results in a much slower turning blower when there is no call for heating or cooling. This reduces the electrical useage as well as providing greater comfort as the air is slowly, continuously mixed, like a slow turning paddle fan in the summer. If you have an electronic air cleaner and/or ultraviolet lights installed for air purification, their operation is enhanced greatly with the reduced airflow and limiting them to cleaning the air just during heating or cooling cycles partially defeats the reason you installed them in the first place. If you didn't install them, I'd recommend you reconsider as tight homes have notoriously bad indoor air quality. Ever wonder why the manufacturers of t-stats ever put a fan 'on' switch on all their stats if people are not supposed to run the system with the fan 'on'??:confused:

As far as the 'ticking' noise is concerned, it could be any one of innumerable things. Call a good service tech and leave the system completely off for a good while before he gets to your home so he stands a good chance of hearing the problem. It could just be the duct rubbing on some wood or sheetrock or something more mechanical. Someone on scene should be able to tell you pretty quickly. :)

[air2spare]

this is an ongoing arguement in our industry and you're certainly entitled to your opinion but you might also consider what happens with fan "on" in the summer time, you remove latent heat while the condenser is running but when the condenser cycles off and the indoor fan stays running it blows air across the wet coil and condensate pan and rehumidifies the same air it just dehumidified in the cooling process ;)







Not particularly good advice. Generally running a variable speed product with the fan in the 'on' condition results in a much slower turning blower when there is no call for heating or cooling. This reduces the electrical useage as well as providing greater comfort as the air is slowly, continuously mixed, like a slow turning paddle fan in the summer. If you have an electronic air cleaner and/or ultraviolet lights installed for air purification, their operation is enhanced greatly with the reduced airflow and limiting them to cleaning the air just during heating or cooling cycles partially defeats the reason you installed them in the first place. If you didn't install them, I'd recommend you reconsider as tight homes have notoriously bad indoor air quality. Ever wonder why the manufacturers of t-stats ever put a fan 'on' switch on all their stats if people are not supposed to run the system with the fan 'on'??:confused:

As far as the 'ticking' noise is concerned, it could be any one of innumerable things. Call a good service tech and leave the system completely off for a good while before he gets to your home so he stands a good chance of hearing the problem. It could just be the duct rubbing on some wood or sheetrock or something more mechanical. Someone on scene should be able to tell you pretty quickly. :)

[tag1956]

this is an ongoing arguement in our industry and you're certainly entitled to your opinion but you might also consider what happens with fan "on" in the summer time, you remove latent heat while the condenser is running but when the condenser cycles off and the indoor fan stays running it blows air across the wet coil and condensate pan and rehumidifies the same air it just dehumidified in the cooling process ;)

Fan on is good for small package units serving office area's so fresh is allways introduced to ocuppied space. But for homes its fan auto

[nubbin]

Just a side note, my dad installed some metal duct in the 60's. When the fan came on after Everything was quiet, he could clearly hear the audio from the local channel 5 TV station.

The ticking may stop when someone kicks it in the right spot (no warranty included).

[roadsideridged]

are the supply pipes all metal to the boot ? if so maybe install a 3 or 4 foot piece of flex at the end of the run. could be the 30 gauge metal expanding and contracting in the unconditioned atic space. is the duct wraped?

[tinknocker service tech]

more then likely the supply duct is tight against wood somewhere. The thing is to find where the ticking is loudest and try shifting the duct a little. Most times it is in the main trunk line nearest the furnace. The installing company should be able to resolve this for you with out to much time involve

you could also have some of the exposed ducts insulated or wraped this will also cut back on the ticking noise and help with heating costs

[Buzzy]

Happy New year everyone!

Gold star sticker to Tinknocker. I was able to shift the ducts a little and wedge little duct tape pads (folded 6" strip of tape over on itself to make 1" rectangle) between the duct and the wood.

Big improvement. Sleeping through night now and it has been very cold here
minus 16 F with windchill. Still some ticking but not all ducts are accessible.

Thanks everyone!

[Buzzy]

In regards to the fan issue... I did some experimenting and for us, it is more comfortable with the fan in "Auto." When the heat is firing all is well, but we find a cool draft between cycles with the fan "on".

When the outside temp. moderates here, I will experiment with fan off/auto again.