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jhoboken
May 2, 2010, 01:49 PM
I have questions about our noise problem coming from our HVAC blower.

We have the return and air flow going straight into the blower (about 12 inches or so of duct work between the blower and return grill):

1. What angle should I have the sheet metal baffle? It seems as if this is the best fix.
2. What does the sheet metal baffle look like?
3. Is there a special noise reducing grill that we can purchase?

My HVAC contractor wants to charge me $750 to produce and install the sheet metal baffle to "greatly" reduce the noise. I have friends who can fabricate the sheet metal baffle if I give them more instructions, but we have no idea about HVAC and metal noise baffles.

Thanks in advance.

PS - the Blow is definitely the issue - its loud!

Joshdta
May 2, 2010, 01:54 PM
What size ac unit? How big is the grill? And how much space between the grill and the furnace?

jhoboken
May 2, 2010, 02:33 PM
I'm not sure how big the unit is, but the grill is about 23 by 18 - the unit takes filters that are 20 by 16 by 1. There's about 14 inches from the grill (straight back) to the blower...

Joshdta
May 2, 2010, 02:43 PM
The best way to reduce the noise is to take all the metal duct out and install flexable, either 12'' or 14'' round, but you would need to know the model number of the furnace or the ac in order to get the size right.

jhoboken
May 2, 2010, 04:09 PM
Is this what you're talking about:

Detailed Part Description and Picture (http://www.mhsupply.com/Part_Detail.asp?SubCategoryPartListing_Action=Find %28%27SKU%27,%2716-5023%27%29&SubCategoryPartListing_Position=FIL%3AORD%3AABS%3A 5KEY%3A16-5023PAR%3A%40Subcategory_ID%3D77)

Joshdta
May 2, 2010, 04:18 PM
Yes something like that, if you can get the flexable duct from the furnace to the grill it will cut the noise to close to half, plus you may be able to turn your fan speed down

jhoboken
May 3, 2010, 01:40 PM
It is an easier job to just buy the sheet metal baffle or to go with your suggestion?

Joshdta
May 3, 2010, 05:22 PM
I have no idea how a metal baffle will work, plus seems like restricting the airflow will make it louder. Either way should not cost no where near $750

Missouri Bound
May 3, 2010, 07:14 PM
Anything that restricts the air flow is a mistake. If you own your home, and if it's possible, spend that $750 to re-arrange ductwork to relocate the return air grill, with insulated ductwork and a longer distance between the blower and return. Anything that restricts air flow will create some problems later, such as increased blower wear, higher operating temperatures for both the blower motor and the system. Moving the return air location by extending the duct will reduce the velocity noise without reducing the air flow.

jhoboken
May 26, 2010, 02:17 PM
Let me know ask you another question –

Our HVAC wasn’t blowing cold air a few weeks ago. It was out of freon, so we had it filled.

Now, the system stops blowing air (although everything is on) after its on a couple of hours.

Our HVAC guy says that there’s a Freon leak and the coil is likely freezing up. He wants to pump the system up with Nitrogen to find the leak.

Thereafter, he says that leak is likely at the coil. And, if so, it was costs $2,200 to replace.

Sound reasonable?

Jeremy

Joshdta
May 26, 2010, 02:41 PM
2,200 to replace a coil? The most expencive coil I have ever seen was around $1200 and that was for a 5 ton super coil. What ton coil do you have? And how old?

jhoboken
May 26, 2010, 02:49 PM
It's a small Goodman unit about 10 years - we have a 1350 sq. ft. condo

Does $2,200 make sense including labor?

Do you think I should switch from out HVAC guy (who does respond quickly) to PSG&E, which is the utility company? Our HVAC guy did miss the leak the first time and just filled it with freon, which totaled $350 for 3 pounds of freon and labor...

Thanks

Joshdta
May 26, 2010, 02:54 PM
What state are you in. man you are getting reamed lol glad prices are not this high here. You have a 2 ton ac? That coil should cost about $550. So inless they are going to charge you close to $1800 labor for a job that should be done in 2 to 4 hrs. This sound way high to me.

jhoboken
May 26, 2010, 03:02 PM
Thanks! I'm in Hoboken, NJ, which is near NYC. Do you know anyone in north jersey?

jhoboken
May 28, 2010, 08:25 AM
I had a new HVAC come in - the freon level was low after being filled a few weeks ago - we decided that he would add freon and a sealer to the system - he thought if there was a small leak, the sealer could hold for a couple of years. He'll then come back in a few weeks. If the freon level is low or the system ices up, he'll do a leak test which takes 2-3 days to determine what to do (i.e. weld a hole, replace compressor, etc.) - thoughts?