94yj
Well-known member
i am getting sick of buying filters every few months and was wanting opinions on the electrostatic filter as i could wash it out twice a month or are they not worth it all help greatly appreciated thanks
electrostatic filters are they woth it
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BillK
Well-known member
yj,
When we replaced our original furnace about ten years ago we switched to the electrostatic type. My Wife noticed the difference almost immediately. Much less of the real fine dust that settles on furniture etc. one thing you have to do is keep up on cleaning them, I try to do it about every 60 days or so and they do get filthy.
When we replaced our original furnace about ten years ago we switched to the electrostatic type. My Wife noticed the difference almost immediately. Much less of the real fine dust that settles on furniture etc. one thing you have to do is keep up on cleaning them, I try to do it about every 60 days or so and they do get filthy.
BillK
Well-known member
Just to clarify, I am talking about the electronic type that are hooked up to 110 volts.
Falcon67
Well-known member
Had one - junk. Lowered the system effecency and could never get it clean. Threw it away this summer after 6 months. Just buy the filters.
Cruzingoose
Active member
Electrostatic filters have no restriction to air flow even when dirty. Any particles in the air are electrically charged by a very high voltage and collected on a stainless steel grid. If really dirty they will "flash over" and a loud spark can be heard. Then it's really time to clean the grid. Dont be fooled by "self powered electrostatic filters". They are not the real deal.
Cleaning is easy. The best cleaners are either Simple Green or Purple Power in gallon jugs. Don't bother with pre diluted spray bottles with the exception of 409. Used straight, decanted into spray bottle, spray and saturate the grid plates and let sit. After a few minutes, spray again then hose off. Very important to let the grid dry completely before putting back into the unit.
Cleaning is easy. The best cleaners are either Simple Green or Purple Power in gallon jugs. Don't bother with pre diluted spray bottles with the exception of 409. Used straight, decanted into spray bottle, spray and saturate the grid plates and let sit. After a few minutes, spray again then hose off. Very important to let the grid dry completely before putting back into the unit.
Today's standard filters are MERV rated. This rating method has been out for about 10 yrs now. The higher the rating number the more efficient the filtration. With that high filtration ability comes high pressure drop...higher restriction to air flow. There is a balance point on every system.
If it was my system I'd buy a Trion Air Bear. It has a 5" pleat. There are many other manuf of these filter frames & cartridges that copy the Air Bear. Filters are a pain in the neck, but if you stay on top of them and change them regularly, they will pay for themselves in system efficiency.
Electronic filters work well, but rather than pulling the filter and throwing it away, you get to remove and clean, carefully, so you don't damage them. I've always felt they degrade over time and when you look at the cost of the electronic vs the cost of a box of 5" pleats, I'll take the pleats. Your replacement schedule on a 5" pleat should be somewhat less frequent given the amount of surface area compared to a standard 1" filter. Look around your area and talk to the HVAC distributors. Buy them by the case if you go that way.
If it was my system I'd buy a Trion Air Bear. It has a 5" pleat. There are many other manuf of these filter frames & cartridges that copy the Air Bear. Filters are a pain in the neck, but if you stay on top of them and change them regularly, they will pay for themselves in system efficiency.
Electronic filters work well, but rather than pulling the filter and throwing it away, you get to remove and clean, carefully, so you don't damage them. I've always felt they degrade over time and when you look at the cost of the electronic vs the cost of a box of 5" pleats, I'll take the pleats. Your replacement schedule on a 5" pleat should be somewhat less frequent given the amount of surface area compared to a standard 1" filter. Look around your area and talk to the HVAC distributors. Buy them by the case if you go that way.
I recommend my customers use regular pleated filters that they can get from home depot or wherever and spray them with Endust before putting them in. They make a special aerosol product to do this job. But Endust works well, most people have it already, it's cheap, and it's already been tested around humans.
Once a month. Easy way to do this is to change them when the power bill comes in. The electric company won't forget to bill you!
If your system can handle thicker filters, then by all means use the thickest one you can. Change time is 1 month per inch. So, a 2 inch pleat lasts 2 months, 4 inch last 4 months, etc.
Many residential systems that take 1 inch pleats have accommodations for 2 inch. Little tabs are in the way to hold the thinner filter in place. Snap them off and the thicker filter could just slide it.
Once a month. Easy way to do this is to change them when the power bill comes in. The electric company won't forget to bill you!
If your system can handle thicker filters, then by all means use the thickest one you can. Change time is 1 month per inch. So, a 2 inch pleat lasts 2 months, 4 inch last 4 months, etc.
Many residential systems that take 1 inch pleats have accommodations for 2 inch. Little tabs are in the way to hold the thinner filter in place. Snap them off and the thicker filter could just slide it.
CWO4GUNNER
Well-known member
Just a recommendation. As a landlord I have found that when it comes to air filtration and air conditioning (heat/cooling), the two are best kept separated. IMO return air flow is important when it comes to reliability of my AC equipment. I personally filter my house hold air with hepa/carbon portable Honeywell air filters and they work great. Im not recommending any particular brand of portable air filter as there are a cornucopia of good choices out there. I'm just recommending that if your central AC/heating system did not come with integrated filtration as part of the designed consideration (none of mine did), that you keep add-on "clean-air" filtration away and separated from your return air. The return air filter that you do use when new should be translucent and your hand visible on the other side. If you cant see through it when new don't use it. Buy a portable air filter.
Here is what I use on my return air systems
Here is what I use on my return air systems
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LS6 Tommy
Well-known member
Electrostatic filters were a fad in the late 90's. Do they work? To an extent, yes. They also flood the house with ozone. Friction static filters work OK, but not as good as a good pleated filter. They're the ones that look like they're made out of monofilament fishing line. They need to be cleaned frequently. If it were me, I'd just buy some good pleated throw always & be done with it.
Tommy
Tommy
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aandpdan
Well-known member
My parents have one of these:
http://www.lennox.com/pdfs/brochures/Lennox_PureAir_System.pdf
My father has had allergies for years and this works.
It's a MERV rated filter, down to .01 microns. There is a UV lamp for killing mold/bacteria. They claim "hospital grade filtration."
http://www.lennox.com/pdfs/brochures/Lennox_PureAir_System.pdf
My father has had allergies for years and this works.
It's a MERV rated filter, down to .01 microns. There is a UV lamp for killing mold/bacteria. They claim "hospital grade filtration."
thanks for all the help guys i was thinking that the electrostatic filters was a fad but i wanted to ask the people in the know the only problem i have is i live in the country on a dusty road and i am changing my filter every week due to dust and dirt also does not help that i have a shepherd and 2 Siberian huskies what is your opinion on cut to fit washable filter also my a coils is 18x16 size and not stocked locally the main filter is 20x20x1 but i am wanting to put filters on the a coil also
pseudorealityx
Well-known member
Here's what I would do. Have your local HVAC guy build you a secondary, oversized filter tray, upstream of the current one. In this new one, buy some very cheap pleated filters with the "lowest" MERV value you can get. This will basically catch the bigger dirt/dust and dog hair, and they're super cheap to replace. Then keep a better filter in the secondary position to get the smaller stuff that gets through the first filter. Feel free to spend a bit more money on this one.
I don't trust any of the washable filters.
I've pulled out hundreds of furnaces over the years, the only ones that the blower compartment is clean are the ones with a thick media filter in a good housing properly sealed to the furnace. The electrostatic filters are never very clean and anything with only a 1" filter will be even worse.
99% of the jobs I install get an Aprilaire or Lennox media filter, the Aprilaire are a MERV 13 and we use the Lennox when we want to go to a MERV 16, 95% of these only need to be changed once a year.
I feel that the filters main job is to protect the equipment, cutting down on dust in the house is a side effect.
If you can only fit a 1" filter don't go buy the super expensive 3M filtrete filters, they are very restrictive as they get even slightly dirty, most of the time the filter slot will leak a bunch of air around them anyways, the couple dollar apiece pleated are fine if that's all you have room for.
99% of the jobs I install get an Aprilaire or Lennox media filter, the Aprilaire are a MERV 13 and we use the Lennox when we want to go to a MERV 16, 95% of these only need to be changed once a year.
I feel that the filters main job is to protect the equipment, cutting down on dust in the house is a side effect.
If you can only fit a 1" filter don't go buy the super expensive 3M filtrete filters, they are very restrictive as they get even slightly dirty, most of the time the filter slot will leak a bunch of air around them anyways, the couple dollar apiece pleated are fine if that's all you have room for.
rockford33
Well-known member
So brewchief, which big box filter would you suggest for allergy sufferers? My wife has bad seasonal allergies so I always have bought the 3M filtrete thinking it would help cut down on them in the house. My 12 year old Trane (80% efficient I believe, 65k btu) has always had a 16x25x1 filter size. Any suggestions?
Thanks,
Neil
Thanks,
Neil
pseudorealityx
Well-known member
Get a tech to build you an oversized 2" or 4" deeep filter bank, and then get a high MERV filter to fit. Oversizing it will decrease the pressure drop without any negative effects. Also, with more filtering media, it will last longer.
CWO4GUNNER
Well-known member
I have thought of increasing the return to the largest filter size available, but still felt that those tight pleated filters restrict too much. But your idea of having two separate media types is really a brilliant idea. One of those ideas that just go over most people's heads. I don't even see a problem with them being side by side. Some of the best ideas are so stupidity simple.
I think the thing that gets in the way of the high MERV units is the static pressure they create in the system. There are lot of good suggestions here, but for the guys doing it all the time, is there anything out there instrumentation wise that tells the homeowner when to change the filter, or if that particular filter is to restrictive?
I have an old Dwyer 100-5 incline manometer for duct static and draft and such. I also use a Fieldpiece and UEI differential manometers, but have only used them for gas pressure setting.
Your furnaces typically will have a max external static of .5". If you take the probe on a manometer and put it in perpendicular to the direction of flow in the supply duct, Just outside the furnace case, you will get a number. Let's say .2" of static. Now do the same test on the return air side and note the number. Let's say it is .5". Adding the two we are at .7" and exceed the furnaces external static requirement. The problem is to high a static on the return. You can back up that return system and will frequently find that the drop out of the ceiling (basement type up flow systems) is undersized. You can pinpoint the restriction and fix the undersized duct
If you did this test on both sides of a new filter and checked it periodically you would know when that filter is ready for change-out. For the cost of the bigger pleats it may be worth doing. Putting to high a MERV unit in a system creates a problem that is like trying to drink a thick milkshake through a skinny straw. Your head collapses!
I have an old Dwyer 100-5 incline manometer for duct static and draft and such. I also use a Fieldpiece and UEI differential manometers, but have only used them for gas pressure setting.
Your furnaces typically will have a max external static of .5". If you take the probe on a manometer and put it in perpendicular to the direction of flow in the supply duct, Just outside the furnace case, you will get a number. Let's say .2" of static. Now do the same test on the return air side and note the number. Let's say it is .5". Adding the two we are at .7" and exceed the furnaces external static requirement. The problem is to high a static on the return. You can back up that return system and will frequently find that the drop out of the ceiling (basement type up flow systems) is undersized. You can pinpoint the restriction and fix the undersized duct
If you did this test on both sides of a new filter and checked it periodically you would know when that filter is ready for change-out. For the cost of the bigger pleats it may be worth doing. Putting to high a MERV unit in a system creates a problem that is like trying to drink a thick milkshake through a skinny straw. Your head collapses!
Stevie-Ray
Well-known member
Electrostatic and electronic are two different things. This is the one I have in my furnace, bought over 20 years ago when I had high-allergy problems. The difference was impressive, and I still have it in that furnace today. Clean it once a month, during use times.
http://www.discountfurnacefilter.com/dust-free-dust-fighter-95-16-x-25-x-1-electrostatic-filter
http://www.discountfurnacefilter.com/dust-free-dust-fighter-95-16-x-25-x-1-electrostatic-filter
CWO4GUNNER
Well-known member
I've pulled out hundreds of furnaces over the years, the only ones that the blower compartment is clean are the ones with a thick media filter in a good housing properly sealed to the furnace. The electrostatic filters are never very clean and anything with only a 1" filter will be even worse.
99% of the jobs I install get an Aprilaire or Lennox media filter, the Aprilaire are a MERV 13 and we use the Lennox when we want to go to a MERV 16, 95% of these only need to be changed once a year.
I feel that the filters main job is to protect the equipment, cutting down on dust in the house is a side effect.
If you can only fit a 1" filter don't go buy the super expensive 3M filtrete filters, they are very restrictive as they get even slightly dirty, most of the time the filter slot will leak a bunch of air around them anyways, the couple dollar apiece pleated are fine if that's all you have room for.[/]
Everything I put in gets a 5" thick merv 11 in a custom insulated cabinet. Every system. Typically change them once a year.
Just a recommendation. As a landlord I have found that when it comes to air filtration and air conditioning (heat/cooling), the two are best kept separated. IMO return air flow is important when it comes to reliability of my AC equipment. I personally filter my house hold air with hepa/carbon portable Honeywell air filters and they work great. Im not recommending any particular brand of portable air filter as there are a cornucopia of good choices out there. I'm just recommending that if your central AC/heating system did not come with integrated filtration as part of the designed consideration (none of mine did), that you keep add-on "clean-air" filtration away and separated from your return air. The return air filter that you do use when new should be translucent and your hand visible on the other side. If you cant see through it when new don't use it. Buy a portable air filter.
Here is what I use on my return air systems
You're recommending the worst filter possible lol.