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MikeVillages
10-26-2024, 08:38 AM
Furnace/AC filter change interval?
Your info/comments and questions?

INFO:
Filter size: 16x25x4
Filter MERV: 10, what the previous owner used.
Square feet: 2000.
No pets:
Occasionally open windows for fresh air.
We usually keep the AC temperature @ 79 as we find that comfortable. The furnace temperature is set much lower.
We usually change around 6 months but think we could go longer.

Kenswing
10-26-2024, 08:42 AM
Interview? Do you mean interval?

We use MERV-11 filters. Didn’t even knew they made a 10. Our HVAC company recommends every six months. I usually go a little longer since it’s just two of us and we don’t have any pets.

Ecuadog
10-26-2024, 09:01 AM
Filtrete 16x25x1, MERV 13... change every 3 months... probably overkill.

villagetinker
10-26-2024, 09:25 AM
We have the approximately 20 by 20, by 4 inch and the recommended interval was 6 months and this has worked well even with a couple of cats.

vintageogauge
10-26-2024, 09:35 AM
We had our HVAC system on a maintenance schedule with Munns every 6 months and the tech always told us the condition of the filter which was good for about 9 months. We bought our filters at ace as it was an odd size and they seem to have everything in there. I might mention that the maintenance is a good thing to have, they caught a few items over the years that needed attention and none of it was at an extra cost.

ThirdOfFive
10-26-2024, 10:00 AM
Six months; same interval as the water filter on the fridge and the air purifier in our bedroom. Amazon carries all three and about a week before change time I just order all three of them.

Amazon is about 20-25% less across the board on each filter.

biker1
10-26-2024, 10:46 AM
You didn't indicate whether the depth was 1" or 4". If 4" depth, once a year is fine unless you have some extraordinary situation. For 1" depth, every 3 months is fine.

Furnace/AC filter change interval?
Your info/comments and questions?

INFO:
Filter size: 16x25
Filter MERV: 10, what the previous owner used.
Square feet: 2000.
No pets:
Occasionally open windows for fresh air.
We usually keep the AC temperature @ 79 as we find that comfortable. The furnace temperature is set much lower.
We usually change around 6 months but think we could go longer.

CarlR33
10-26-2024, 12:42 PM
Assume you’re living there full time so I would just check it at 3 and then six months changing more/less often based on usage, etc. It’s not likely to do any impact to the system unless you get to a year or more

MrFlorida
10-26-2024, 02:05 PM
Every 6 months

Topspinmo
10-26-2024, 06:24 PM
When even you think it’s dirty enough cause your situation probably different? Mine according 4” filter last year or more unless weather unusually dry. But, I have angel hair filters on the intake which catches the big stuff, I change that every 4 to 6 months. And no it don’t affect air flow cause I measured before and after at ducts outlets. My ducts flow 350 to 580 CFM.

MikeVillages
10-27-2024, 04:24 AM
You didn't indicate whether the depth was 1" or 4". If 4" depth, once a year is fine unless you have some extraordinary situation. For 1" depth, every 3 months is fine.I have 16x25x4 and updated my post. Thanks

RICH1
10-27-2024, 04:55 AM
once a year with a 4 inch thick filter...

Rustyboy
10-27-2024, 05:20 AM
I buy my filters off Amazon, Munn's changes it when they do the 6 months maintenance.

retiredguy123
10-27-2024, 05:37 AM
I use a 16 x 20 x 4 MERV 11 filter and change it every 6 months. I buy them from Filterbuy on Amazon. I have found that the MERV 11 filters make the house quieter and less dusty than the standard MERV 8. They don't seem to limit air flow.

Bness
10-27-2024, 05:38 AM
Furnace/AC filter change interval?
Your info/comments and questions?

INFO:
Filter size: 16x25x4
Filter MERV: 10, what the previous owner used.
Square feet: 2000.
No pets:
Occasionally open windows for fresh air.
We usually keep the AC temperature @ 79 as we find that comfortable. The furnace temperature is set much lower.
We usually change around 6 months but think we could go longer.

More pleated filters have more surface area. I would recommend 20 plus pleates at Merv 11 to 13. If you run your system normally with no pets and no smoking, you should get a year. Check the first of every month after 6 months and see what it looks like.
Also buy by the box. 4 inch filters come 6 to a box and the case cost is much cheaper. They don't go bad if kept dry.

MikeN
10-27-2024, 06:03 AM
I change ours at the beginning of each season or every three months. We do have pets but that doesn’t seem to be an issue. Doing it a bit more frequently lets the air handler not push as hard. My choice

Miboater
10-27-2024, 06:30 AM
You didn't indicate whether the depth was 1" or 4". If 4" depth, once a year is fine unless you have some extraordinary situation. For 1" depth, every 3 months is fine.

I have a friend who owns a heating and cooling business up in Michigan and he recommends your schedule. Change a 1" filter every 3 months and a 4" every year but check them at the halfway point to see if there is any unusual condition.

dewilson58
10-27-2024, 07:33 AM
once a year with a 4 inch thick filter...

:eclipsee_gold_cup:

La lamy
10-27-2024, 07:43 AM
I change mine every 6 months. They usually look totally fine, but I’d rather still change them that often.

HJBeck
10-27-2024, 07:59 AM
Recommend you move up to MERV 13 as a minimum, annual changes. We use a MERV 16 due to allergies and change annually. We have no pets.

CoachKandSportsguy
10-27-2024, 08:08 AM
thinking about cutting corners with maintenance costs?

always a poor tradeoff, the expense is minimal compared to a full replacement or having a clogged filter and adding extra cycles to keep the house at temperature. .

find the cheapest supplier to save money, not extending in service service past the recommended life. .

retiredguy123
10-27-2024, 08:08 AM
Recommend you move up to MERV 13 as a minimum, annual changes. We use a MERV 16 due to allergies and change annually. We have no pets.
In my opinion, if you use a higher MERV rating, I would change the filter more often than every 12 months.

OhioBuckeye
10-27-2024, 08:29 AM
I know you have to use Actual size or they won’t fit.

Dilligas
10-27-2024, 10:37 AM
Furnace/AC filter change interval?
Your info/comments and questions?

INFO:
Filter size: 16x25x4
Filter MERV: 10, what the previous owner used.
Square feet: 2000.
No pets:
Occasionally open windows for fresh air.
We usually keep the AC temperature @ 79 as we find that comfortable. The furnace temperature is set much lower.
We usually change around 6 months but think we could go longer.
Merv 13 part #FILXXFNC0021 19.125 X 19.8125 X 4
FILTERBUY.COM auto 1/year @ $82.33 for 2 filters

I change every 6 months but during pollen seasons every 4 months.....my wife has allergies and asthma.

DrHitch
10-27-2024, 09:35 PM
Change your furnace filter at the SAME TIME as you change batteries in the smoke detectors....you DO THIS every 6 months...right?

retiredguy123
10-28-2024, 01:39 AM
Change your furnace filter at the SAME TIME as you change batteries in the smoke detectors....you DO THIS every 6 months...right?
I change HVAC filters every 6 months. I never change smoke detector batteries until one of them starts to beep. The batteries are just for backup when you lose power. Alkaline batteries should last 4 or 5 years, and lithium batteries will last 10 years. Changing them every 6 months is an outdated recommendation and way too often.

Marathon Man
10-28-2024, 06:33 AM
I change HVAC filters every 6 months. I never change smoke detector batteries until one of them starts to beep. The batteries are just for backup when you lose power. Alkaline batteries should last 4 or 5 years, and lithium batteries will last 10 years. Changing them every 6 months is an outdated recommendation and way too often.

Agree.

Chee-Chee
10-28-2024, 07:49 AM
4x19x20 merv 11 filter. I stock up from Lowe’s they have a pretty good price. I do it when the water filter on the refrigerator needs replaced because that is my reminder :-) price at Lowe’s is about 17 bucks. I was just there and there were on sale

DrHitch
10-28-2024, 07:53 AM
.....I never change smoke detector batteries until one of them starts to beep. The batteries are just for backup when you lose power...."

True...My comment was more for standalone battery detectors, not those that are AC hardwired with battery backup. Yes, it's really best to simply replace the entire unit with one with a 10-year lithium battery.

Regorp
10-28-2024, 08:02 AM
Furnace/AC filter change interval?
Your info/comments and questions?

INFO:
Filter size: 16x25x4
Filter MERV: 10, what the previous owner used.
Square feet: 2000.
No pets:
Occasionally open windows for fresh air.
We usually keep the AC temperature @ 79 as we find that comfortable. The furnace temperature is set much lower.
We usually change around 6 months but think we could go longer.

Be aware of the fractions on the size as it makes a BIG difference to fit properly.

swally
10-28-2024, 08:14 AM
Filtrete 16x25x1, MERV 13... change every 3 months... probably overkill.
Not for those thin ones. 1” is a monthly change. Depends on quality too.

retiredguy123
10-28-2024, 08:30 AM
True...My comment was more for standalone battery detectors, not those that are AC hardwired with battery backup. Yes, it's really best to simply replace the entire unit with one with a 10-year lithium battery.
I would just comment that standalone detectors with replaceable batteries wouldn't comply with the current Electrical code. All detectors must be hardwired, or if you build a room addition, you must use a sealed detector with a permanent battery.