Browsing HD yesterday, I noticed there are about 4 different versions for our size. All were at different price points.

Are they basically the same or do the higher cost ones really that much better at filtering out undesirable particles?

Any good online sources for filters?

No. You get what you pay for. The important thing is to change your filter monthly without fail. If you have allergies there are higher end electrostatic filters available. Heating and AC guys may know of more options.

Monthly? I change mine twice per year. Damn things are expensive.

The better ones filter out smaller particles and miscellaneous other stuff. Shop them by MERV rating.
Decide how small you want to filter out then buy online in case quantity. You'll save a lot that way.

ZSMICHAEL, I'd be interested if you (or anyone else) could expand on this.

I change mine monthly during the winter as the furnace is running every day. But, in Spring and Fall, and Summer if the air is not running a lot, I push out replacing the filters for 60 or even 90 days.

I also tend to buy the cheapest I can find. So, I'd also be interested in hearing if there is good reason to buy more expensive filters.

Thanks.

quote:

I also tend to buy the cheapest I can find. So, I'd also be interested in hearing if there is good reason to buy more expensive filters.

^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
I live in the Deep South. The other offices adjoining mine have ALL had their offices flooded because the drain pipes backed up due to not changing filter regularly and using an Algaecide regularly in the drain. It is cheap insurance against a major hassle. My filter is not disposable and I take it out and clean it monthly. Having a clean filter means the system does not have to work as hard to circulate air.

If you have pets and dust it is even more important.

quote:

Originally posted by 220-9er:
The better ones filter out smaller particles and miscellaneous other stuff. Shop them by MERV rating.
Decide how small you want to filter out then buy online in case quantity. You'll save a lot that way.

^^^ Yep, this ^^^

Cheap filters are fine as long as the filter rack will keep them in place.

More expensive (read this as, more restrictive) 1" filters can harm (shorten the life) your heating and cooling equipment.
When going this way, you should verify proper airflow by measuring the temperature rise across the furnace.

1" electrostatic filters pretty much kill HVAC equipment and efficiencies.

If you need better air filtration, one should go with a 3-5" thick media filter.

Mine is 5" thick. It gets changed once a year and almost looks clean.

quote:

Originally posted by Excam_Man:
Cheap filters are fine as long as the filter rack will keep them in place.

More expensive (read this as, more restrictive) 1" filters can harm (shorten the life) your heating and cooling equipment.
When going this way, you should verify proper airflow by measuring the temperature rise across the furnace.

1" electrostatic filters pretty much kill HVAC equipment and efficiencies.

If you need better air filtration, one should go with a 3-5" thick media filter.

Excam, I very much value your input on all things HVAC. I use 1" MERV 8 filters in my returns. Are these good or bad as far as the life of my HVAC system is concerned? I had been using the inexpensive green fiberglass filters but changed to the MERV 8 filters when the new system was installed.

An HVAC guy I trust told me to just change it often. He said the high dollar ones aren’t necessary if you do that.

quote:

Originally posted by marksman41:

I use 1" MERV 8 filters in my returns. Are these good or bad as far as the life of my HVAC system is concerned? I had been using the inexpensive green fiberglass filters but changed to the MERV 8 filters when the new system was installed.

It really depends on the size (btu), efficiency (80/90/92/95/96%/etc) and specs (temp rise) of the furnace and the square inches of the filter/s.

The one sure way to find out, is to measure the temp rise across the furnace. Measuring the intake (return air) and the outlet (supply air) temperatures. The difference is the increase in temp across the heat exchanger. Then see if it falls inbetween the spec listed on the furnace data plate (sticker). It will be located on the inside of the furnace.

I like to see the temperature rise in the middle of the given specs (30 degrees of recommend temp rise). This way the heat exchanger isn't running cool (causing damage by condensating in the primary heat exchanger) and leaves some room to increase, as the filter accumulates airborne particles. You don't want it operating at the high end, as when the filter starts getting dirty and restricting airflow, you now have a heat exchanger operating outside of the recommended specifications (stressing it until it cracks or causing many other premature failures).

You can adjust the temperature rise by increasing (lowers outlet temp) or decreasing (raises outlet temp) the fan speed.

sometimes the higher filtration ones have an adverse affect on airflow volume.

I'm confused. So far we have been told that you get what you pay for to the more expensive ones can harm your system.

quote:

Originally posted by Bassamatic:
I'm confused. So far we have been told that you get what you pay for to the more expensive ones can harm your system.

As far as filtering goes, yes, you get what you pay for.... better filtration.

That doesn't mean they are good for your equipment.
With better filtering, there's much more at stake to maintain proper airflow. Correct filter size for equipment, area of media, filter rack design, runtime vs change intervals, etc. This is assuming the system was designed correctly in the first place. Which most systems are not. So having a restrictive filter just amplifies the existing issues.

I'm a firm believer in having good filtration on HVAC equipment. Which is why every system should be protected by a media filter, 3-5" thick, properly sized (16x20, 16×25, 20x20, 20x25). To reduce equipment failures, keep the system clean and operating at peak efficiencies.

Most systems are limited to the 1" filters (measuring 3/4" in thickness).

Many thanks, Excam!

My HVAC guy recently told me the filter is there to protect the HVAC equipment, not to remove dust and pollen in the air of your home. That was an interesting statement, if it’s true.

Many filter companies claim their filters will keep your home cleaner. I don’t know what to believe at this point. Any comments on this are welcome.

quote:

Originally posted by Edmond:

Any good online sources for filters?

Check your phone or iPad for a text message from me.

quote:

Originally posted by Edmond:

Any good online sources for filters?

One of the forum members is in the filter business. I bought 12 filters from him for each of my returns. I only replace them every 6 months and have 4 of each left so it's been a while since I've ordered and can't remember who it was. Hopefully he'll chime in to this thread.

quote:

Originally posted by 12GA:
Monthly? I change mine twice per year. Damn things are expensive.

Ditto