AC question. Pros or know it all’s

[WCB]

This is my first house with central heat/air so bear with me.

There is a filter in the return air vent but not one in the unit in the attic. There’s a spot for it in the attic unit and there’s not one installed. Is the one in the return air vent ok or should I run both?

[Gerald G]

I only use the one inside the house in the return.

[CabezaBlanca]

Saw the title and thought this was about Antler Collector. He’s a pro and a know it all!

[Lights Out]

I would just use one at the unit itself. I think using two would choke the airflow which will cause stress on the blower motor. I’m no ac guy though. Just my 2 cents

[HogHunter34]

X2 filter at the return into blower unit
I have return vents cut out along the base of a wall but no filters there but one in the filter slot of the unit housing of the blower
I wouldn’t double up as to starve the air handler any as this could impact cooling

[WCB]

Saw the title and thought this was about Antler Collector. He’s a pro and a know it all!

lmao

I would just use one at the unit itself. I think using two would choke the airflow which will cause stress on the blower motor. I’m no ac guy though. Just my 2 cents

X2 filter at the return into blower unit
I have return vents cut out along the base of a wall but no filters there but one in the filter slot of the unit housing of the blower
I wouldn’t double up as to starve the air handler any as this could impact cooling

I was curious about starving the unit if I used two but needed to ask. Which ever one I end up using it’ll be one that traps everything.

[StrayDog]

Do you have duct going from the return vents to the condenser in the attic? Regardless, I’d rather have the filter at the condenser unit (i.e. @ the unit in the attic). The reason being is most people think the filter is to “filter the air” in your house. While this is true, it’s equally as important to keep the cooling coils clean. Dirty coils = reduced cooling capacity. The closer the filter is to the coil, the better chance you have keeping the coil clean.

Be careful about putting the baddest mamma jamma filter you can find. In general, for a given size of AC filter, the better it is at filtering out gunk, the more pressure drop you’ll get. It’s possible to damge/reduce your units life span by using a super duper filter that puts excessive strain on your condenser blower fan.

[Wits_End]

I use the one in ceiling to keep return ducting from collecting loads of dust. AC guy said didn't matter either way really, but sided on ceiling return and not in unit

[topshot]

In regards to filters, more surface area is better. If your unit can take a 3 inch pleated filter vs a 1 inch, you get 3x more surface area, equating to lower differential pressure and an easier task for your motor. Plus it will last longer before needing a change.

[WCB]

Do you have duct going from the return vents to the condenser in the attic? Regardless, I’d rather have the filter at the condenser unit (i.e. @ the unit in the attic). The reason being is most people think the filter is to “filter the air” in your house. While this is true, it’s equally as important to keep the cooling coils clean. Dirty coils = reduced cooling capacity. The closer the filter is to the coil, the better chance you have keeping the coil clean.

Be careful about putting the baddest mamma jamma filter you can find. In general, for a given size of AC filter, the better it is at filtering out gunk, the more pressure drop you’ll get. It’s possible to damge/reduce your units life span by using a super duper filter that puts excessive strain on your condenser blower fan.

I was thinking MERV 13 was the max I was going. Just checking if one or two filters.

In regards to filters, more surface area is better. If your unit can take a 3 inch pleated filter vs a 1 inch, you get 3x more surface area, equating to lower differential pressure and an easier task for your motor. Plus it will last longer before needing a change.

1” max at either spot. Every month.👍

[Chadhender]

I use the good 6” filter up in the attic to protect the unit and the cheap floss filters in the returns.

[tpack]

Do you have duct going from the return vents to the condenser in the attic? Regardless, I’d rather have the filter at the condenser unit (i.e. @ the unit in the attic). The reason being is most people think the filter is to “filter the air” in your house. While this is true, it’s equally as important to keep the cooling coils clean. Dirty coils = reduced cooling capacity. The closer the filter is to the coil, the better chance you have keeping the coil clean.

Be careful about putting the baddest mamma jamma filter you can find. In general, for a given size of AC filter, the better it is at filtering out gunk, the more pressure drop you’ll get. It’s possible to damge/reduce your units life span by using a super duper filter that puts excessive strain on your condenser blower fan.

This is exactly what I was going to say, but I`m not a pro. Just read enough and watched enough videos on the matter on filtering and return air.

[bowhntrmatt]

Only run one or the other. Filters are inherently restrictive and stacking them will do way more damage than good.

If both filters are the same size, I would use the filter location at the unit.

If the ceiling return is bigger (example- ceiling filter is a 20x30 but the filter rack at the unit holds a 20x20) I would put the filter at the ceiling return as the larger filter will be less restrictive.

[bowhntrmatt]

If you really want the unit to last, have an AC guy install an Aprilaire media filter in the attic. only change 1x per year, nothing gets through it, and it flows air way better than any 1" filter out there.

[AntlerCollector]

Saw the title and thought this was about Antler Collector. He’s a pro and a know it all!

Recognize!