HVAC return vents in Our homes
 

Question for those in the know. We have a 10 year old Designer. The Return vents in the ceiling seem to have no filters.

Do newer or older homes here have any? The only filter we have is directly in the Air Handler.

The return vents between living areas are designed for balance of airflow and comfort

This is correct, one filter in the air handler, change every 6 months.

Ok, My old previous house I put intake vent filters in ceiling (down flow system) when I had my ducts cleaned. (they were lot bigger than 1 foot square return vents in my house in villages which I don’t think go back to furnace but back to air distribution box in attic? On new designs.). That filtered the air before it entered the furnace. That was older system and hand no extra return ducts.

IMO the problem with adding them plus the in furnace filter it MAY? restrict air flow (only why to know check with Anemometer ) Which you might have to speed fan to push more air which put more stress and may cause motor to fail prematurely? Or it may not? If you do it I would check air at vents. Last time I check requires around 350 feet per minute (Ft/min) air flow per ton rated unit? At vents?

Besides my house here the return vents in each room are small, if you’re are same? I doubt you can get one to fit in small hole?

You only need one filter for the house located at the air handling unit. Some of the manufactured houses have the ducts located under the floor with an outside packaged air handling unit. These systems have the filter in the wall where the return air duct is located. It would not be efficient to have more than one filter unless you had multiple zones or multiple HVAC systems.

I used a filter in my return vent (1") in the hallway between the bedrooms until I had a complete
new HVAC.
The installer said use the 4" filter on the new unit and Never use the one in the return vent

From OP. Great. Thanks all. I was concerned that the build of our home HVAC was wrong. A couple Sales guys for equipment said it was odd that our house did not have additional filters in the returns.

Just shows what they -don't- know. Now I know. Thanks again for the clarity.

Feel good there is only 1 main filter. Costs to remove and/or clean multiple filters would be 3-4X higher

Once a year is fine with a high quality filter.

As Keefelane66 posted, those are not return vents. They are to balance the air between areas that might be closed off such as a bedroom if you shut the door and the rest of the house. We have a yearly maintenance contract on our A/C and I asked the guy one visit why we had two vents in our bedrooms. He said he ran across a house that did not have them and the people's bedroom got very warm if they shut the door. He installed the balancing vent and the problem was solved. Cool air can't get in if the warm air can't get out.

Only one filter in the air handler, change every 6 months.

Only one main filter, none in individual vents.

Keep the doors open to all rooms for proper airflow.

They are return ducts
 

You are correct that these are in fact return ducts. They comments about not being returns and are for balancing air flow are both correct and incorrect. They are individual returns that go to a main trunk line return that will go to your air handler. They also are individual returns to allow conditioned air to enter and exit a closed off room. This would be my preferred way to have a system designed and installed by the way.
I like to replace filters quarterly myself. Although they do look like they could easily go 6 months. I figure filters are cheaper than a coil cleaning. Recently we switched to a washable type of filter. I will clean it on a quarterly basis also.

The filtration is set up near the air handler unit. The interior return vents help the air flow. No need for filters.

Airfilters
 

My home is two years old and the only filter I have is located in the unit. If you have concerns over the return vents and dust/dirt have the vents cleaned by a professional. Then add a good filter to your system.

Good luck

Air duct cleaning? -
Cleaning Air Ducts - What Would Bob Do? - Bob Vila

Sometimes while doing construction where there is dust from sanding sheetrock compound the builder will put temporary construction filters on each return to prevent dust from going into the ducts and remove them when completed.

A very large majority of homes have only one filter, which should be located at or close to your air handler the VillageTinker is correct, you should change the filter every six months typically. However, it really needs to be changed every time it gets very dirty, so if homes are a little dusty. They may change every three months. the return, if there’s an obstruction such as dust build up clogged air filters can cause your air handlers coil to ice up and stop giving air-conditioning in the warmer months
A filter creates friction which makes air have to work harder for air to pass through it. If not enough air passes through coil in the air ice out air can’t get through at all. The more filters in a home, the harder the system has to work to overcome the friction (drag) of the filters.

ADDITIONALLY
if you are pumping air into a space - as the A/C does, there needs to be a means of escape or source of outlet (somewhat like avoiding a balloon effect in a closed space)

the Primary Return is typically the larger 24x24 grill in the ceiling of the living space, and since that is usually a 10 ft high ceiling, the filter is provided in the Air Handler for convenience of replacement (3 month intervals is highly recommended)

I personally have opted for automatic delivery of the Air Filter from Lowe's in the 3-month intervals so I do not have to mark my calendar

and that also reminds us of the recommended 6-month System Maintenance inspection (annually for the Water Heater)

Oh, they know. They are hoping you don’t and you’ll fall for their BS and let them sell you a whole new system.