Hvac air filters

[Earl E Retyre]

I just finished changing all the hvac air filters in the house. I do it every 3 months like the package says. But they never really look dirty to me. I begin to wonder if I could change them less frequently. Do you change every 3 months?

 

[skipro33]

I do the same; every 3 or 4 months. Doesn't look dirty until I hold it up to the new one. Then I see. Remember the old laundry and toothpaste commercials where they show the teeth or white t-shirt, then strip away the dingy yellow? You don't see it until you can compare it.

 

[braumeister]

I look at it in three months, then month by month to see when it starts getting noticeably dirty. I typically change it at around the five month point. But they're hardly expensive. I pay around $15 each.

 

[MC Rider]

They get dirty faster since we got 2 cats in here.
OK, hairy not really dirty.

 

[Bamaman]

Filters stay cleaner and last longer if your floors are hard and if they're kept especially clean.

We're using Rosie the robot vacuum about every other day, and we cannot believe how much cat and dog hair she gets up. We're 100% hardwood floors.

 

[Jerry1]

Mine is 5 inches wide and runs about $30. I change it every six months. They don’t look particularly dirty, but you can tell they are dirty. I like to change it out just before allergy season and then again in the fall. Basically one filter for the air conditioning season and one for the heating season.

 

[arbeadub]

I see it as reduced efficiency of moving the air, up to the point of reducing the flow rate, the more a filter has collected the less particles get through to be redistributed. A new filter has larger pore space letting more dirt through.

 

[MC Rider]

I see it as reduced efficiency of moving the air, up to the point of reducing the flow rate, the more a filter has collected the less particles get through to be redistributed. A new filter has larger pore space letting more dirt through.

Depends on the filter you buy, they are not all created equal.

 

[CardsFan]

Mine is 5 inches wide and runs about $30. I change it every six months. They don’t look particularly dirty, but you can tell they are dirty. I like to change it out just before allergy season and then again in the fall. Basically one filter for the air conditioning season and one for the heating season.

Mine are like this (Aprilaire 210). Just replaced it yesterday. They said it would last a year, and it did, but it was pretty dirty. Next time maybe 8 months. They are MERV 11, so not HEPA, but pretty efficient.

 

[RobbieB]

I'm seasonal. With 2 dogs they are brown and furry when I take them out. Buy them by the 6 pack online.

 

[Piper20]

Carrier MERV 15, $90. Change once a year. One dog, Beagle mix.

 

[rk911]

I just finished changing all the hvac air filters in the house. I do it every 3 months like the package says. But they never really look dirty to me. I begin to wonder if I could change them less frequently. Do you change every 3 months?

I change every 6.

 

[RetiredAndLovingIt]

I run the heating Nov thru March and change the filter twice and then don't change it again till late August since i don't usually turn on the a/c until then if at all. So 3 times a year and use pleated MERV 8. I buy 12 at a time and may upgrade to Merv 11 next time since my allergies are getting worse.

 

[RE2Boys]

Once a year,MERV 8, 4 inch thick box filter, about $25 each.

Very timely post, I had to go check mine, it's due to be changed next month (April). No pets. We heat until mid to late May. Each year I hope we don't need the AC, some years we only need AC for a few weeks but recent years have been at least a month.

 

[COcheesehead]

I run a Merv 11 in heating months. They are about 5” thick. One lasts 5-6 months. In Summer it was recommended to switch to a one inch filter because it won’t put as much stress on the AC. I change those about every two months in AC season.

 

[OldShooter]

Depends on the filter. More pleats, longer time between changes. More pleats=more surface area to collect stuff.

 

[Jerry1]

I run a Merv 11 in heating months. They are about 5” wide. One lasts 5-6 months. In Summer it was recommended to switch to a one inch filter because it won’t put as much stress on the AC. I change those about every two months in AC season.

How do you change to a one inch filter? The holder is wide. Do you have a hack to hold the thinner filter in place?

 

[COcheesehead]

How do you change to a one inch filter? The holder is wide. Do you have a hack to hold the thinner filter in place?

?

The holder is a flat ledge. It will take one inch to probably an eight inch tall filter. The air sucks it downward.

 

[Jerry1]

?

The holder is flat ledge. It will take one inch to probably an eight inch tall filter. The air sucks it downward.

Mine stands on its thin edge and the air moves through it horizontally. I think when the air is on, it would be fine, but when the air shuts of, it’s going to tilt and that’s when I wouldn’t be sure it gets sucked back into place during the next cycle. I might play with it a bit and see if I can rig something up. Given my allergies, I wouldn’t mind changing out the filter more often in the spring/summer.

 

[COcheesehead]

Mine stands on its thin edge and the air moves through it horizontally. I think when the air is on, it would be fine, but when the air shuts of, it’s going to tilt and that’s when I wouldn’t be sure it gets sucked back into place during the next cycle. I might play with it a bit and see if I can rig something up. Given my allergies, I wouldn’t mind changing out the filter more often in the spring/summer.

I have four ledges, one on each side, about an inch wide that holds the filter in place. Haven’t had an issue.

 

[Jerry1]

Mine looks like this. Go to about 1:15 on the video.

 

[COcheesehead]

Mine looks like this. Go to about 1:15 on the video.

Mine sits horizontally.

 

[jazz4cash]

My old thermostats had a built in filter monitor. It was set to 600 hrs of fan runtime from the factory. I monitored the condition of the filters and adjusted the change interval accordingly. 700 hrs equated to approx 4 months using merv 8 filters and they were just starting to look worn. We use 6 filters so this was significant costwise. Now my new fancy IOT tstats don’t have that feature. If the filter looks almost brand new after 3 months i might leave it in longer but if Im prone to forget to check it 1 month later i’d just replace it anyway.

 

[pacergal]

Depends on the MERV rating and filter, but generally every 3-4 months, more often in winter when the furnace runs, less in spring and summer as we don't use the AC very often, but will run the fan on hotter days to circulate cooler air at night.
We have been getting the three pack at Costco, Filtrate for Pollen, Allergy and Asthma.

 

[Montecfo]

Depends on the filter. More pleats, longer time between changes. More pleats=more surface area to collect stuff.

More pleats = less air flow right?

I just have to wonder about the efficiency of the more expensive "higher efficiency" filters. Don't they do the same thing a lower efficiency filter that is dirty does: reduce air flow?

Perhaps someone can explain to me what I am missing here.

I tend to think.you want to buy cheap filters and replace more often to get the greatest efficiency.