How often do you change furnace filter ?
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i change mine every three months to keep the dust down. since I have one good lung left, I don't go cheap with the filters. I use the ultra filtrete. I buy filters in bulk though. I have a nest thermostat on our first floor to save me even more money.
I change our quarterly. Easy to remember.
All that other stuff is another OCD.
All that other stuff is another OCD.
I have a washable filter. I usually clean it twice a year.
Monthly during the heavy heating/cooling seasons. Every other month otherwise, give or take.
On this forum the pros and cons of changing a car's air filter too often have been discussed. Much like your vehicle's filter, HVAC filters catch more stuff as they become loaded. Changing too often does not result in "better" filtration, but may result in lower restriction. The higher MERV (or, whatever rating the mfg happens to use) filters do need to be changed more frequently. Since I started running my blower continuously I do find that the longevity of the filter can vary with ambient conditions. Higher humidity generally means less dust floating around in the air.
I hate dusting and rarely do it. So, by running the blower all the time I, at least, don't have people writing their names in my dust (my GF did that once). I did expect my electric bills to increase a bit, but my winter bills are still running about $50 (I have gas heat.) I am guessing the blower motor on my unit is not that big. Since I work for an HVAC mfg I verified that the prevailing opinion is that the motor will last longer running it this way. It's 17 years old at this point and I am capable of replacing it myself.
I hate dusting and rarely do it. So, by running the blower all the time I, at least, don't have people writing their names in my dust (my GF did that once). I did expect my electric bills to increase a bit, but my winter bills are still running about $50 (I have gas heat.) I am guessing the blower motor on my unit is not that big. Since I work for an HVAC mfg I verified that the prevailing opinion is that the motor will last longer running it this way. It's 17 years old at this point and I am capable of replacing it myself.
Patman
Staff member
In my old townhouse I would change it every 3 months and it was always pretty dirty. I ran the fan for the furnace/AC all the time though. In my current place, I only have the fan set to run when the furnace/AC is actually active, and I only change the filter when the thermostat recommends it (which is based on hours of usage) and that ends up being only about every 6 or 7 months, and at that time it doesn't even look very dirty at all (but I still change it) I always use the premium filters that trap more allergens, I found the cheap ones clogged up too fast (which seems odd since they don't filter out as fine as the premium ones)
Here is a Merv 8 filter that has about 2 months on it in my 1960s Air Ease. Does this look dirty enough to change? I usually change them about this time because it makes the furnace fan run forever to cool the heater box. I don't think the limit ever trips, but I have read that higher efficiency filters in old furnaces are not a good combination, but I can't find spun fiberglass filters locally.
Thoughts? Either that or the fan switch thingy needs replacing? Sometimes after the gas shuts off via the thermostat, the fan will run for a long time. In fact, it's actually stuck on before. I thought maybe the airflow was reduced from these high efficiency filter to the point it doesn't cool off the furnace fast enough, therefor the blower runs longer.
Thoughts? Either that or the fan switch thingy needs replacing? Sometimes after the gas shuts off via the thermostat, the fan will run for a long time. In fact, it's actually stuck on before. I thought maybe the airflow was reduced from these high efficiency filter to the point it doesn't cool off the furnace fast enough, therefor the blower runs longer.
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OVERKILL
$100 Site Donor 2021
On an old style belt drive furnace blower, yes, according to my furnace guy, the high efficiency filters can overheat the motor.
On newer direct drive models no, they don't.
And to put some perspective on your picture, the filter in my furnace is that dirty after one cycle of the blower (really old house... pets). I think yours looks pretty darn good!
On newer direct drive models no, they don't.
And to put some perspective on your picture, the filter in my furnace is that dirty after one cycle of the blower (really old house... pets). I think yours looks pretty darn good!
Drew, that's about what my merv8 filters look like after 3 months, which is when I replace them. However, I haven't found much difference in airflow from my HVAC between them and fresh filters.
Thanks guys.
Originally Posted By: OVERKILL
On an old style belt drive furnace blower, yes, according to my furnace guy, the high efficiency filters can overheat the motor.
On newer direct drive models no, they don't.
And to put some perspective on your picture, the filter in my furnace is that dirty after one cycle of the blower (really old house... pets). I think yours looks pretty darn good!
Yikes! Have you considered having your ducts professionally cleaned?
On an old style belt drive furnace blower, yes, according to my furnace guy, the high efficiency filters can overheat the motor.
On newer direct drive models no, they don't.
And to put some perspective on your picture, the filter in my furnace is that dirty after one cycle of the blower (really old house... pets). I think yours looks pretty darn good!
Yikes! Have you considered having your ducts professionally cleaned?
OVERKILL
$100 Site Donor 2021
Originally Posted By: Drew99GT
Originally Posted By: OVERKILL
On an old style belt drive furnace blower, yes, according to my furnace guy, the high efficiency filters can overheat the motor.
On newer direct drive models no, they don't.
And to put some perspective on your picture, the filter in my furnace is that dirty after one cycle of the blower (really old house... pets). I think yours looks pretty darn good!
Yikes! Have you considered having your ducts professionally cleaned?
I manually cleaned them (the run to the furnace on the cold air side is short) last year and they aren't that bad. But between some reno going on with the plaster, the dog, the cat, 3x small kids....etc. It gets pretty dusty.
Originally Posted By: OVERKILL
On an old style belt drive furnace blower, yes, according to my furnace guy, the high efficiency filters can overheat the motor.
On newer direct drive models no, they don't.
And to put some perspective on your picture, the filter in my furnace is that dirty after one cycle of the blower (really old house... pets). I think yours looks pretty darn good!
Yikes! Have you considered having your ducts professionally cleaned?
I manually cleaned them (the run to the furnace on the cold air side is short) last year and they aren't that bad. But between some reno going on with the plaster, the dog, the cat, 3x small kids....etc. It gets pretty dusty.
I change mine annually. I don't use my furnace or central A/C much. My window A/C unit that I use a lot I do clean it's filter a 2-3 times during the summer.
Apparently I forgot to replace my filters last time, so this one has over 5 months on it...
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