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[ultrarunner]

Have not come across multiple ducted returns in residential.

Standard is one or more registers in each room/area with a single return in a common hallway when ducted or below the furnace if not ducted with the furnace location commonly in the hallway.

It may be because still very little central A/C here?

The few that have added Central A/C to Central Heat use the existing floor registers.

 

[WM75Guy]

Have not come across multiple ducted returns in residential.

Standard is one or more registers in each room/area with a single return in a common hallway when ducted or below the furnace if not ducted with the furnace location commonly in the hallway.

It may be because still very little central A/C here?

The few that have added Central A/C to Central Heat use the existing floor registers.

It is not uncommon here in Texas. The air handlers tend to be in the attic, so running duct is easy. Our 2 units in the house have multiple return air ducts. There is one 24"X 24" in the hallway for each unit and then 12" X 12" in the rooms where the doors tend to be closed, like the master bedroom, my office, and the media room.

 

[2manyrocks]

what kind of duct did they run in your new house, Torvy? Water line material? I haven’t looked at new house construction in so long I don’t know what materials they use now.

 

[Sigarms]

Have not come across multiple ducted returns in residential.

If you look at the image the OP gave on his air handler, at this point in time there is no ducted return. I'm assuming the supply duct is coming off the top of the air handler, and it may not be in the picture. That said, that definately looks like a sheet metal filter rack under the air handler (which I originally thought was a drain pan) which tells me they are running the return air directly under the air handler (why they would put the air filter there). If they are going to run any type of return duct to the air handler, it's going to be impossible with the dehumidifier directly under the return air of the air handler.

In NC, it's code for anything over 1,600 sq ft to have two return ducts.

 

[ultrarunner]

It could be here most homes here built long ago prior to newer code.

1993 build of 3200 square feet one return...

It does make sense to keep the air balanced...

My largest commercial package unit with two compressors serving the lobby will overcome door closers and prevent exterior doors on a 32,000 square feet building from fully closing during filter replacement for the brief period of time return air is coming from outside air...

 

[Torvy]

what kind of duct did they run in your new house, Torvy? Water line material? I haven’t looked at new house construction in so long I don’t know what materials they use now.

I don't know the technical terms. Most of it looked like metal ducts. I can take a shot of the attic to get a better idea. The ducts in the attic in the old place look like giant plastic versions of dryer vent ducts.

 

[Sigarms]

I don't know the technical terms. Most of it looked like metal ducts. I can take a shot of the attic to get a better idea. The ducts in the attic in the old place look like giant plastic versions of dryer vent ducts.

Before the house was being built, did you tell them where you wanted your HVAC system?

Assuming all your air registers (for both supply and return) are in the ceiling?

Apologies, I missed it, how many floors? 1 with the attic?

I'm also under the impression that you have no clue who the HVAC contractor is? Assuming he's local and will most likely be handling the service for at least the first year (at least that's required in NC for new installs).

 

[Torvy]

I told them where I wanted all of the utilities. The room was designed specifically for that purpose. Water heater, HVAC and Elec. panel all in there) House is a single sloped roof. One story with a partial attic over the bedrooms. Mechanicals room is in the SE corner of the house. The outdoor unit, is just outside the door there.

The main living area is lofted, so it looks bigger than it is.

This shot is from the kitchen toward the family room. MB is on the other side of fireplace wall (there is another fireplace in there). This is the only shot I have right now where you can see vent/ducts. Front door is to the left, back door to the right. The ducting in the foreground is for the cook top hood.

 

[Sigarms]

I told them where I wanted all of the utilities. The room was designed specifically for that purpose. Water heater, HVAC and Elec. panel all in there) House is a single sloped roof. One story with a partial attic over the bedrooms.

You did your due dilligence IMO building your new home. I won't lie, knowing some homeowners, I could see the HVAC contractor laying out the duct work in the attic with equipment and THEN you change your mind where the equipment should be located after everything is built

IF you were my father, this is the same advice I'd give to him in the same situation as yourself, so I'm being honest with you...

Manual J (load calculation)
Manual D (duct calculation)
Manual S (equipment selection per Manual J)
Manual ZR (zoning calculation)

For new construction, a Manual J and Manual D should be done and followed at a minimum.

In NC, a Manual J must be done by law per new contruction, and the only time it is required to be produced is if there is an issue from the end user.

Per the state you reside in,

Contact Information

www.tdlr.texas.gov

I'm not a big permit kind of guy (another can of worms depending on who you deal with), but as a paying end user, your expectation is you assume the guy doing the work for you knows what he is doing and you won't have any issues.

This is not always the case.

I've seen a newly built 3,200 square foot single level home only need 2 ton of AC in NC (non LEED certified). New construction along with higher insulation values do not go by the old school rule of thumb per square footage anymore for heating and cooling loads.

I'm a dummy. Don't trust anything I say, but talk to people more smarter than myself in your local area per this topic.

That said, when your HVAC system is started up, I'd highly suggest you get a basic start up sheet that the HVAC company should do for their own records which they should supply to you per your request. You should have static pressure given as well as CFM's produced by the air handler (as well as your charge on refrigerant). Honestly, for a new home build, I'd also have the contractor verify how many CFM's are being produced at each and every register when the system is running full tilt.

You're spending good money on this build, and if people are making money on this job, their expectation should be that you are satisfied IMO.

A man much smarter than myself once told me that you can't verify results if you don't record the data at hand at that point in time. Keep a record of those verifications in writing so if you have an issue down the road, you can verifty the results vs a previous "good" test. This will help you narrow down the possible issues if one arises in the future.

You may never have an issue, and open returns may cause no problem (although technically any open return by code in NC needs to be "plenum rated" which raises other concearns if there is a problem), but if your HVAC company is pulling return air for the air handler in a a single room for a 2,000 sqare foot house, I would have concearns about it myself. That said, I'm a dummy and don't know what I'm talking about, but... if they (the installing HVAC company) has a whole house dehumidifer installed with the air handler, for the money being spent, standard good practice is to tie in the dehumidifiers supply and return into the supply and return ductwork for your HVAC system. The way it looks per your pic, there is no return to tie the dehumidifier into and an "open space" return is being used. I could be totally wrong about that because the work isn't finished yet.

That said, if an open return is being used from the room the equipment is in, your basic start up sheet will catch any potiential problems with static pressure and CFM's.

For only one HVAC system for that sized house, I'm surprised no one offered you zoning options if there are only two of you living in the house that size (impression I get from reading this thread is it's you and the misses). Bascially that will only give you the required heating and cooling for say the master bedroom and master bath late at night, when you and your wife generally aren't anywhere else in the house. By heating and cooling only one bedroom and perhaps bath were the owners sleep at night, it reduces the total load for the entire home running off of one system when the load is only required for a bedroom and bathroom 8 hours a day (say 11PM to 6AM). Then, if you don't spend any time in the bedroom during the day, it can help shift the load to the rest of the house (thermostat is used for each "zone" to control the temp).

 

[2manyrocks]

HVAC installers I've dealt with seem to hate doing the calculations. I think they'd rather work in a blazing hot attic than actually run the numbers.

IMO, one the smartest moves for a homeowner these days is to also install a mini split to cool and provide some heating in the large open area (typically the open kitchen/entertaining space). Very efficient, super quiet, and can keep the big area you actually use during the day comfortable. The larger ducted system then can heat and cool the closed off bedrooms and bathrooms as needed maybe at a higher temp during the day when not in use, but at whatever temp needed at night.

Although it's not a true zoned system, the other advantage to me is that if there is any problem with the central ducted system, at least the mini split is there to maintain some comfort while the central is being sorted out and vice versa because they are independent systems.