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Michael
Air filters for round vents

My son suffers from very bad allergies. We currently have a 13 air filter and have had all the ducts cleaned, however we are also looking for air filters for the vents themselves for his room only. Downfall is when they installed this heating system about 20 years ago, they installed the vents in the ceilings of the second floor and they are the round commercial style.

Does anyone know of any round vent filters on the market?

motoguy128
Re: Air filters for round vents

You can't put filters in supply grills. It will restrict airflow and reduce the "throw" of the supply register. The throw is what mixes the air in a room and helps keep temperatures even. Reducing airflow can damage your air conditioner and.or your furnace. IF you damage the heat exchanger on your furnace you will get CO2 and possibly carbon monoxide as well. Carbon monoxide detectors don't detect low levels that could still make you sick. Only higher levels that will kill you. Some pros recommend low level carbon monoxide detectors if you have gas appliances.

There's no reason to do this. IF you have a Merv 13 filter and have cleaned the supply ducts, filter at the grills won't do anything. To filter further, you'll need a supplemental HEPA filter.

Before you do that, I would make sure that you're controlling humidity and bringing in fresh air. "the solution to pollution is dilution"... as they say. As a ventilating dehumidifier and a HEPA filter and you'll be in great shape. You could also add a UV light, but I think those are mostly a waste and unessesary.

Some HEPA filter units can bring in fresh filters air as well as can some dehumidifiers.

The absolutely best thing you can do to remove fine dust is to vaccuum frequently with a vacuum with a HEPA filter on the exhaust. You homes HVAC system isn't a dust collector. IT won;t capture more than maybe 10% of you home's dust at most. The rest you need to remove with a vacuum, mopping or dusting.

Vacuum bedrooms almost daily if you child is very sensitive. That's where most dust is. Keep humidity under 50% in summer and over 40% in winter when it's over 30F overnight and 20-40% when colder overnight.

Have your attic inspected for mold as well as make sure you don't have any moisture in your basement.

Michael
Re: Air filters for round vents
motoguy128 wrote:

You can't put filters in supply grills. It will restrict airflow and reduce the "throw" of the supply register. The throw is what mixes the air in a room and helps keep temperatures even. Reducing airflow can damage your air conditioner and.or your furnace. IF you damage the heat exchanger on your furnace you will get CO2 and possibly carbon monoxide as well. Carbon monoxide detectors don't detect low levels that could still make you sick. Only higher levels that will kill you. Some pros recommend low level carbon monoxide detectors if you have gas appliances.

There's no reason to do this. IF you have a Merv 13 filter and have cleaned the supply ducts, filter at the grills won't do anything. To filter further, you'll need a supplemental HEPA filter.

Before you do that, I would make sure that you're controlling humidity and bringing in fresh air. "the solution to pollution is dilution"... as they say. As a ventilating dehumidifier and a HEPA filter and you'll be in great shape. You could also add a UV light, but I think those are mostly a waste and unessesary.

Some HEPA filter units can bring in fresh filters air as well as can some dehumidifiers.

The absolutely best thing you can do to remove fine dust is to vaccuum frequently with a vacuum with a HEPA filter on the exhaust. You homes HVAC system isn't a dust collector. IT won;t capture more than maybe 10% of you home's dust at most. The rest you need to remove with a vacuum, mopping or dusting.

Vacuum bedrooms almost daily if you child is very sensitive. That's where most dust is. Keep humidity under 50% in summer and over 40% in winter when it's over 30F overnight and 20-40% when colder overnight.

Have your attic inspected for mold as well as make sure you don't have any moisture in your basement.

It is unconditioned up there and well vented. The last inspection did not find any mold or moisture issues, but who knows.

I will put a humidifier in his room when I get home tonight. As it is, we are setting up his 'big boy' room in a another room and we hope he does not have the same issues in there.

Sten
Re: Air filters for round vents

I don't know what type of supply grills you have but Home Depot or Lowes have a type of filter that you can cut to fit inside the register or grill, if it is absolutely necessary. As moto says, there should only be one filter so you don't restrict air flow

motoguy128
Re: Air filters for round vents
Sten wrote:

I don't know what type of supply grills you have but Home Depot or Lowes have a type of filter that you can cut to fit inside the register or grill, if it is absolutely necessary. As moto says, there should only be one filter so you don't restrict air flow

Bad, very bad. IT will restrict the flow too much, and they aren;t any better than a standard MERV 10 filter.

Again, stick with a 4" or 5" media filter and if needed use a MERV 13 filter. But you're better off looking for a portable or whole house ducted HEPA filter unit.

dj1
Re: Air filters for round vents

Frankly you've done a lot to improve the air quality in the room.

Try a portable air sterilizer (google and find stores. Sharper image is one).

Sten
Re: Air filters for round vents

If it's an expense thing you can use the cut to fit till you get or can afford a ducted HEPA filter, but don't plan on using them long term as they are restrictive to air flow

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