my house sounds like a jet engine when hvac turns on (rental, houses)

[PNWGuy]

Granted the house I purchased was previously a rental and wasn't outfitted with the highest quality finishings, but I am dumbfounded why both hvac resonate so loudly through the vents when they turn on - I can't even hear the tv it because the sound coming from the vents are so loud. I can't tell if this is due to hvacs being lowest quality units in the world, or the way then ducts are shaped, or what. I've had four houses here in pacific nw , all had hvacs and never made this much noise.

Is this an AZ thing or do I need new hvac units?

[Zippyman]

Originally Posted by PNWGuy

Granted the house I purchased was previously a rental and wasn't outfitted with the highest quality finishings, but I am dumbfounded why both hvac resonate so loudly through the vents when they turn on - I can't even hear the tv it because the sound coming from the vents are so loud. I can't tell if this is due to hvacs being lowest quality units in the world, or the way then ducts are shaped, or what. I've had four houses here in pacific nw , all had hvacs and never made this much noise.

Is this an AZ thing or do I need new hvac units?

Are you hearing noise on the air return side, or the individual room ducts?

Many homes here have undersized air returns, they do make a "low restriction" filter grille cover that can increase return airflow by about 10-15 % while reducing the noise a bit.

The brand of system has little to do with the sound it produces..

[PNWGuy]

all the noise comes from the vents that output the air. Its like the force of the air is hitting the insides of the ducts where it bends/turns and vibrates loudly.

[Zippyman]

How old is the home? Most homes built here since the mid 1980's have insulated "flex ducts".. those are usually pretty quiet unless they're kinked..

homes built before that with metal ductwork are usually *really* leaky.. (and by leaky, i mean 20% of the air you put in leaks out before it gets to the rooms)..

Fwiw, I know APS has an energy audit rebate, as well as rebates for duct sealing & repair.. might be worth checking into...

[PNWGuy]

Eh, I was afraid of that as well. 1970s home, 8" ducts above the ceiling, no attic. Should be interesting.

[AZJoeD]

There are many different reasons for your situation. It could be as simple as an unbalanced system or as complex as an incorrectly sized unit (too big or too small). It may have been incorrectly installed or just not working correctly.

As Zippyman mentioned leaky ductwork counts for the highest lost of efficiency in most systems.

Also, since you are complaining about this now, is it your heating cycle that is annoying you? Is is better on the A/C cycle?

I think you are going to need to have an Heating & AC contractor come out and take a look. Of course they will try to sell you something, but just tell them to explain your problem first so you can decide what you want to do.

[Zippyman]

I would do the energy audit through the power company. They wont pay unless the contractor does the checks correctly.. and the cost is mostly paid by your utility company... there are a *lot* of very expensive hacks running around in the hvac business..

If you arent noticing problems getting rooms to warm up and cool down, its likely a waste of money to go very deep into the issue, unless it's just so annoying that the noise is keeping you from sleeping.

Even brand-new systems have compromises, and they do things much differently now than they did in the 1970's when it comes to ductwork.

[AZgarden]

My master bath sounds that way when the heat pump kicks in. The heat pump s right outside that wall and is so much louder than the old one that I replaced last March. I had no idea it would make such a difference but it is really loud. Not the whole house, thank goodness.

[TiredOfyycCold]

Originally Posted by PhxBarb

My master bath sounds that way when the heat pump kicks in. The heat pump s right outside that wall and is so much louder than the old one that I replaced last March. I had no idea it would make such a difference but it is really loud. Not the whole house, thank goodness.

Ours is like that too Barb - also a new unit....
I'm going to follow Zippyman's advice and have an energy audit done... and also have them check the noise that the heat pump makes to ensure that the noise is "normal" even though it sounds highly abnormal to me!

[tiger08]

I see that here once in a while, yes sometimes it is poor ducting but most of the time its because someone installed too large of a unit. Newer units move more air than older units, most people oversize instead of doing whats best, like replacing windows and adding insulation. Tigheten up the home first, then have a load calculation done, may be surprised that you could install a smaller, quieter system.