Noise from AC Units. Please help

[stg]

Recently i had to change the AC units in a villa. The old carrier ducted type units were replaced with new trane ones mostly with TWE050A which maches with the old units. However the new problem is the noise. The ducting etc is well sized with medium velocity. But the customer complains of noise which disturbs him and is true. We tried reducing the air flow with a fan regulator and the noise came down. But will that create icing in the unit.? Cooling is not a problem as the units are a bit oversized for the given space. Is there any other solution to just bring the noise down. Now we cant do any major change as the ceilings are closed.

[NCHeat]

liner in the duct?

[stg]

Liner is already done entire length for both supply and return

[Stamas]

Check the R/A grills for the noise.

[stg]

3 slot diffussers are used and there seems no noise generated from the grille. The noise is kind of that heard from unit.

[dorff]

I'm assuming the noise is from the indoor unit, but what kind of noise is it? If you already have liner installed, good airflow (medium velocity?) and no noise from the registers themselves, then you're looking at the fan motors? Can you switch them out to Evergreens?

[fincomber569]

Recently i had to change the AC units in a villa. The old carrier ducted type units were replaced with new trane ones mostly with TWE050A which maches with the old units. However the new problem is the noise. The ducting etc is well sized with medium velocity. But the customer complains of noise which disturbs him and is true. We tried reducing the air flow with a fan regulator and the noise came down. But will that create icing in the unit.? Cooling is not a problem as the units are a bit oversized for the given space. Is there any other solution to just bring the noise down. Now we cant do any major change as the ceilings are closed.

Your post seems like DIY, read the instructions with the indoor unit the answer is in there.
What exactly is a Villa?

[big sky hvac]

Recently i had to change the AC units in a villa. The old carrier ducted type units were replaced with new trane ones mostly with TWE050A which maches with the old units. However the new problem is the noise. The ducting etc is well sized with medium velocity. But the customer complains of noise which disturbs him and is true. We tried reducing the air flow with a fan regulator and the noise came down. But will that create icing in the unit.? Cooling is not a problem as the units are a bit oversized for the given space. Is there any other solution to just bring the noise down. Now we cant do any major change as the ceilings are closed.

I would have to disagree with you on this statement. You're probably having more problems because they are oversized. The run times are probably short and frequent, which means you're not removing as much humidity. By slowing the fan speed down on the blower motor may reduce the noise, but it may also cause the A/C to freeze up due to lack of airflow. It's hard for us to say if slowing the fan speed down will cause the A/C to freeze up because we don't know what size air handlers you have, what the cfm is, or what size the A/C units are. What's the sq.ft. of the villa? What are the sizes of the equipment? How many supply runs are there? How many returns and what size are they?

[jtstuart]

Some noise is probably because these units are oversized for the duct work? a gurl once told me size matters! :angel:

[Skip1]

What the heck is a fan regulator? Cooling not a problem but its icing up? Give us something we can work with....

[fool4school]

Can you install a vibration eleminator to the duct work??

[Paymemore]

I would have to go with big sky on this. Not much of what you are saying makes sense at all. Unit is oversized, but matched old unit? How do you know it oversized? Your saying that you installed a fan regulator and slowed down the fan speed and the noise went down? That would lead us to believe its not just slightly oversized, but grossly. Then that leads into size of duct and blah blah blah. Low airflow from being undersized duct can easily cause your icing up. And why on earth did you put a commercial grade unit with non variable blower in all these villas? Who ever got you to buy these got you good. Matching Tonage is not the same thing as matching units.....

[alphaeus]

If your duct system is undersized you/ll need to ductulate it add trunk and perhaps a run or two. as well you can put balancing dampers next to the trunk for the noisier runs. I ve seen this before where you match an old 22 system to 410 a only to find that the fan is way oversized for the old duct system. you do run a risk of freezing up, being incorrectly charged and losing effiency if duct isn't calcualted before a refit. good luck . Start from the beginning always and calculate the duct work you have in a system to make sure the first instalation was done right and you'll have less problems in the long run.