Furnace Filters

Rhodie Ranch

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I researched furnace filters. Actually its a return air filter in the main floor in a hallway. I read and read and shopped Amazon too. I learned that altho filters now have some numbers scaling their effectiveness at filtering, its not always the right thing to use the higher numbers ones. Sometimes on older units, the higher numbers make the furnace over work itself and then it kills the system.

My furnace was installed in 2001 when the house was built. I've never changed the air filter (been here since May 19) so got out a ladder and climbed up to the 9' ceiling to see what size to buy. The one in there was caked and was an inexpensive one from Ace hardware. I went to wally world and bought a $13 one. I put it in and its got a slight howl to it.

I read and reread the directions. This morning that howl gets me to thinking. Did I do it wrong? The instructions say: "Insert filter into the designated opening in your home furnace or air conditioning system with the ARROW ON THE FRAME POINTING TOWARD THE BLOWER MOTOR."

So I assume that the blower motor is up there in the ceiling cavity. I re-got out the darn ladder, banging it all the way from the garage into the house, set it up and took out the filter. Reversed it. No more small howl.

Online the instructions say to point the arrows towards the furnace, which is out in the garage "over there somewhere".

Really? Does it have to be this hard? Hows a self sufficient woman supposed to know these things? I know...by learning, but gosh, which is the correct way to place that 3M Filtrete filter into the ceiling cavity? Isn't the return air just that - air sucking up into that cavity to go to the furnace to be reheated?

Allergen Defense 1200 Air filter by 3M.

And another thing while I'm frustrated. Upstairs in my rental room (where I have no renter right now) there are two ceiling vents. The vent covers are fixed, that is they cannot be closed off. That room is toasty warm but since there is nobody in there and I'm freezing down below, what can I use to close off those vents and then close the door to try to retain as much of the furnace heat as possible downstairs?
 

majorcatfish

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okay heres a couple older a/c tips

1. have an a/c-heating person come out and have them do a coil clean...on the coil at the furnace. this will let your fan motor work more efficient in the long run. < this only pertains to if you have a heat pump system><not gas>.

2. depending on the filters that fit your return the ones at the super market are fine <just get the pleated ones> since you have animals.....plan on changing them once a month or two< you have to keep an eye on them if they look dirty change them>
2a. as for the filters yes the arrows do need to point towards the furnace.

3. are the vents connected to the force air system? if so you need to un screw one and take it to your home improvement store and purchase a couple that will shut....
or if the vents are just passive<not connected to the force air system> would suggest getting some magnetic sheets and cut them to fit over the vents......

will be sending you bill for this advice......:hugs
 
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flowerbug

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i love that it says what it does, but what it doesn't help you with is what happens if the blower motor isn't pointed the direction you think it should be? or is it always guaranteed to only be pointing one direction?

what makes sense to me is that it should have the arrow pointing in the direction of the air flow and state clearly as such.

we have to crawl through the crawl space under the house to replace the air filter. it gets done twice a year. one chore i hate to do as i have to crawl over some pretty hard cement footings and down through the access panel. just not very easy or convenient. Mom has a horrible time doing it with her bad knee. they'd have done so much better having the furnace put in the corner of the garage and making the garage a few feet bigger. just didn't think it through...
 

Ridgerunner

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2a. as for the filters yes the arrows do need to point towards the furnace.

I'll copy Step 2 from the online instructions to install this filter. And the link.

Step 2

Find the airflow arrow and point it toward the AC/heating blower.


Why are you and 3M going out of your way to make this confusing? Like Rhodie said, a lot of people don't know the intricacies of how their ACHV is set up. How many people know where the blower or furnace is in their system?

Rhodie, a main purpose of that filter is to keep trash out that can grind up your AC fan and cause you to have to replace it. Therefore the filter needs to be downstream from the fan. That means the air is passing through the filter toward the fan. So the arrow points in the direction of air flow. I don't know any simpler way to say it, line the arrow up with air flow. The air is going from the room into that vent so point it away form the room.

Rhodie, my Air Conditioning, Heating, and Ventilation man would approve of that filter. He really does not like the washable ones.

I had to replace the ACHV unit in the last two houses I bought pretty soon after I bought them. Thousands of dollars, each over $15,000. I won't go into details but I was not happy. I have a system set up that I change the filter every two months whether it looks that dirty or not. That's a lot cheaper than replacing that unit. So on the beginning of every odd-numbered month I change it. March is an odd-numbered month so I'm about a week away. Set up your own system.

My return is a 30" x 30". I can't find a filter of the type I want that fits. So I got a box of 14" x 30" and another box of 16" x 30". I tape two of those together and have one the right size.
 

seedcorn

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For those challenged, when fan is blowing, point arrows in direction air is moving.

I change mine every month. Cheap repair bill as I buy them by the case. I just filter out the big stuff so I don’t buy the micro, micro particles. I got stern lecture by installer about changing filters or pay for repairing system-not cheap....
 

majorcatfish

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@Ridgerunner is that just fun writing out the check when you have to replace your ac/heating system.. did that last april..

looked around and found your 30x30 filters dang they are proud $$ of that size.....
 

flowerbug

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I'll copy Step 2 from the online instructions to install this filter. And the link.

Step 2

Find the airflow arrow and point it toward the AC/heating blower.


Why are you and 3M going out of your way to make this confusing? Like Rhodie said, a lot of people don't know the intricacies of how their ACHV is set up. How many people know where the blower or furnace is in their system?

yep! thank you! arrow in direction of air flow... --->
 

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