[elwood911]

Hi All,

I'm looking for some advice on a new HVAC system that was installed in my home yesterday. I've already contacted the installer and he is coming back out later in the week to review the setup in light of this issue, but he doesn't seem to think that there is going to be much he can do to solve this problem, so I want to tap into your collective expertise in case there is something I can ask or suggest that might help.

The new system is a 16 seer Goodman and the blower in question is in a GMES801005CN furnace. I can pull model numbers for the evaporator and condenser, too, if that would be helpful, but they are matched 3.5 ton components and the real issue seems related to airflow/air noise. The unit that was replaced was a 21 year old Trane that was a budget model when installed, judging from the very poor efficiency rating on the yellow sticker it wore.

The problem is that the new unit is significantly louder than its predecessor, and because it's installed in a closet with returns located in walls just beneath it (one in the hallway and the other, smaller/quieter one in an adjoining bedroom), the noise can be heard EVERYWHERE in this 2000 square foot single-story house. The returns have no filters, the filter is located at the base of the unit. I know this blower is supposed to be multi-speed, but it always sounds like it's blowing at high speed. It also seems like the system cycles on more frequently than the old one did, but that could be a misinterpretation based on how much more obvious the noise is.

The installer has mentioned possibly installing a baffle in the box where the two returns are, but I'm having a hard time expecting that to solve the problem, and I'm worried that impeding the airflow will cause as many problems as it solves.

Is there anything else I can ask him to check? Maybe the fan has a speed setting that can be adjusted without making the airflow too low for the size/square footage? I really wasn't expecting an HVAC thats 21 years newer to be louder in a way that negatively affects the perceived quality of my house like this, and in fact I mentioned noise when discussing which new unit to install, and was told that it will be quieter than an older system, but of course now it's too late to change models so I'm really hoping there's something that can be done.

Thanks for any help or guidance you can provide.

 

[pecmsg]

How was 3 1/2-Tons sized, like for like?

Was static pressure readings taken (doubtful)

Without TESP readings there guessing at the actual speed!

 

[beenthere]

Multispeed, only means it can be set to run at a different speed then just high/full speed. Not that it varies its speed while it runs. Yeah, a bit of a misleading term.

So was the old furnace a100,000 BTU input furnace? Or was it only a 80,000 BTU input furnace.

It can be set to run at a lower speed, and the contractor can double check to make sure it has a proper temp rise in heating, and a proper temp difference in cooling mode. Kind of sounds like he left it set at factory default, which would be high speed in cooling mode. And on that furnace that would be for a 5 ton A/C, not the 3.5 ton your suppose to have.

Surprised you only have an 80% efficient furnace.

 

[elwood911]

Like for like. Exactly.

 

[elwood911]

Thanks beenthere. I'll ask him to check that. I live in Texas and it's August, so I was really only thinking about AC, but I was kind of surprised to see such a low efficiency furnace was selected. I assume they were just replacing what was there, but I also had to request 16 seer, since they just default quoted me at 14 seer initially.

 

[Bazooka Joe]

What’s the complete model numbers of the outdoor and coil number, can tell if they installed AHRI matched system. Briefly looked at AHRI web-site using a 3.5 ton OD unit says if your using a Goodman coil, looks to need a 48/60 4/5 ton rated coil to get the 16 SEER, and if they used a CAUF coil as an example you need to use the TXV ( which is a optional field install metering device ) as mentioned static pressure and temperature rise across the heat exchanger and a start up/ commissioning report should have been done. Things like amprege draws of motors and compressor, final field refrigerant charge number matches what Goodman specifications say. Etc. Etc. Did they leave a report on the job site. What’s their definition of matched systems, all parts are the same color and are Goodman products, or its a AHRI matched system.

The wiring diagram looks to show at least 4 speeds blower motor.

Hopefully someone registered your system as Goodman gives outstanding manufacturers warranty if registered. California and Quebec need not be registered to receive the manufacturers maximum warranty.


Did they mention the Tax Credits and possible rebates to you?

The Federal Tax Credit and any rebates your state or local utility company may comes into play if your A/C meets a minimum threshold which is usually 16 SEER and a certain EER.

https://www.energystar.gov/about/federal_tax_credits/non_business_energy_property_tax_credits

Page 21 and 22 discusses the temperature rise across HX and checking static pressure amoung many other things. Dated 8/2019

https://www.ecomfort.com/manuals/508f2495690c6e8a15cc696ab31408da.pdf

See if there is any tiny holes in the location shown, if it has them, looks like they checked the static pressure?

 

[elwood911]

Thanks very much Bazooka Joey!

Condenser: GSX16S421
Coil: CAPF4961C6
Furnace: GMES801005CN

The system has been registered. I'll check into rebates and look for tiny holes when I get home later.

 

[Bazooka Joe]

Condenser: GSX16S421
Coil: CAPF4961C6
Furnace: GMES801005CN

Says that Combo gives you 16 SEER and 13 EER, should be good enough for the Federal Tax Credits and any rebates your state or local utility company may have.

AHRI number 204112301 says you need the field install TXV to get that number. If your under the impression and paid for a 16 SEER rated system you need that type of metering device. It’s externally mounted next to the coil where the liquid line hooks to it. Do you have one?

https://www.google.com/url?sa=t&rct...jACegQIBxAB&url=https://www.ahridirectory.org/&usg=AOvVaw1Psb39iTznxCFNAi8fJHHj

Hit select in blue, then AHRI number in blue to view the certificate.

It says +TXV after the model number of the coil.

https://www.google.com/url?sa=t&rct...DkwQFjAAegQIARAC&url=https://www.dsireusa.org/&usg=AOvVaw19WUxQBTiQc0GVu13UMfK_

 

[Mr Bill]

A 100,000 in a closet, I bet it sounds like he's at the airport. I know Joey said is was a match, and I believe it, but a 100,000 on a 3.5 ton? I remember back in the day when Ruud was using a 100,000 for a 3-ton 16 seer, we did a few, but all attic jobs. I just don't understand why these mfg. have to have so much airflow to achieve a certain seer/eer that is all science to me, but it sure seems like the latent sure will suffer. I don't know much about Goodman, but I really doubt you will ever slow that motor in that 100,000 to quieten it much. Ruud makes a 75-4 for a 4-ton, and it's pretty quiet, so why does Goodman need a 100,000 for a 3.5 ton? If airflow is the key to part of achieving the 16 seer/eer ratings, does that mean Goodman needs a 100,000 to move the same air as Ruud's 75-4?

 

[elwood911]

Thanks again Bazooka Joey! There is an expansion valve fitted. I can't find any holes where thermometers or nanometers might have been inserted, but to be fair the return doesn't have any duct where one might have been drilled and the upper section of the closet is a but cramped so I could be missing one. I'll ask the installer when he comes next time and make sure the tests were conducted.

 

[elwood911]

The owner of the company came back out today and lowered the speed of the blower, which had been left at factory default high, as beenthere suspected. That took care of most of the noise issue, but he also installed a baffle in the return, so the system is now like a whisper. I asked my wife to verify that the new noise level was OK, since she was the most concerned about how loud it was, and her first question was "is it on?"

He also found a few other issues, like missing insulation around the TXV, a misconfiguration in the switches installed in the drain line and some air leaks in the ductwork at the top of the closet. He took some pictures before fixing things and said he would use them as training aides for his installers. It was a very professional remediation, and I'm a happy homeowner again.

Thanks once more for the input and advice received here. This is really a fantastic resource for people like me and I really appreciate the time and effort you all put into helping others like this.

 

[BaldLoonie]

Glad you quieted it down.

The old Choo Choo would have been 80% 21 years ago. There wasn't anything lower since 1992.