How much better is an electrostatic air filter than a 3M Ultra Allergen 1250 filter?
Hello, My house has a 18 year old forced air heating system. It works trouble free since we moved in at 2000. It does not have an electrostatic air filter. I have been using the best 3M filters. The thermostat keeps tracking the hours of use of the filter. When the heater blows air, my nose can feel some kind of discomfort. It is worse when a filter works for 200 hr and more. I am thinking to install an electrostatic air filter, but do not know if it is better enough to get rid of the discomfort. It may need some duct work to put an electrostatic filter. So the first thing I need to find out is how much better an electrostatic air filter is than a 3M Ultra Allergen 1250 filter? Thanks.
First have your furnace checked for carbon monoxide by a trained pro.
At 18 years the furnace could be failing, especialy if you have been using such a restrictive filter. Electronic air cleaners produce ozone so most will tell you to stay away from them. I like the Aprilaire line of filters, see thier web site. I dont't care for the electrostatic filters,
most are to restrictive and need regular washing.
When you say "electrostatic filter" I presume you are talking about an Electronic Air Cleaner (EAC). While some contractors who post to this site have had success with EAC's, I think generally the opinions are negative. The reason is that the efficiency of the product declines rapidly as it gets dirty. There are some extensive threads on this site on EAC's. I would suggest you review them before making a decision.
As to your question regarding the efficiency of the Ultra Allergen filter vs. an EAC I think they are about the same for particles that would make you sneeze such as pollen, dander and mold. Last time I checked the Ultra Allergen was tested as a MERV 11. The only issue I have is that the Ultra Allergen has a relatively high pressure drop. I would not use it on an 18 year old system. 3M has another MERV 11 filter that is less expensive and is less restrictive. I would switch to that filter or another MERV 11.
And as to the reason why you sneeze after the filter has run for over 200 hours, it could be that as the filter has gotten dirty (and even more restrictive). This added resistance is forcing "filter bypass" allowing the allergens to enter your breathing space. After all air is always going to follow the path of least resistance.
If you have filter grills, the more restrictive filters could actually be causing more allergens to enter the home than if you use less restrictive filters, especially after they have started getting dirty.
Restrictive filters in filter grills will cause any leaks in the return ducts to be much worse than if you used less restrictive filters. Those leaks are often from dirty areas.
Either way, chances are good that the 3M filters you are using are far to restrictive for your existing duct system and furnace blower.
Excellent point. I never really thought about this, but of course it is true. You probably notice this all the time when customers are using good filters, have filter grills and dirty coils.
Thanks. As you say - You never stop learning.
It looks like that a too restictive filter could choke the return air and force some unfilted air bypass the filter through gaps around the filter housing. I'll try another less restrictive one. Thank you all, especially breath_esay.
It's been my observation that an electrostatic air filter is made of a material that produces a slight static charge when air flows over it. This static charge encourages dust to stick to the filter. Many so called permanent filters are also electrostatic. The electrostatic air cleaner is washable (most people put it off because of the inconvenience). They end up being a big problem. 1/3 of the ones I've seen are seldom cleaned and that creates the service call I'm there for.
A Electronic air cleaner (EAC) requires power and works similarly to the Ionic breeze cleaners sold by sharper image. It has a corona wire that charges the dust particles and the dust settles on collector plates.
Honeywell makes the industry standard EAC of this type. These need to be cleaned every month or so and become so useless when the collector plates are dirty. Most of these I've seen have had the collector plates replace by a media filter.
The only one still in use that I've observed is used by a bedridden smoker. The collection plates get coated with tar and nicotine and I clean them every month as a service call.
It helps in this situation only because of the regular cleaning. It's the only filter on the furnace/AC and has been working fine for years. She also has several portable HEPA filters in her apartment.
There are a few electronic air cleaners with filter materials as part of the unit. Aprilaire makes a nice one that has an 4 or 5 inch deep media type filter included (maintain every 6-12 months).
Both Maytag and Amana have a 1 inch deep electronic air cleaner with filter pad that's ok. Maintain when dirty, in many homes that's every month.
Most 4 or 5 inch media type filters have dust free blower areas in the furnace.
Many EAC's and electrostatic filters don't.
The Aprilaire EAC with an integrated media filter have dust free blower areas.
These all assume the area between the filter and the furnace or air handler are well sealed. The blower door and any holes for wire penetration are well sealed.
Poor installation craftsmanship and lack of maintenance will cripple the finest equipment.
Last edited by allan38; 03-08-2007 at 06:49 PM.
“I am for doing good to the poor, but...I think the best way of doing good to the poor, is not making them easy in poverty, but leading or driving them out of it. I observed...that the more public provisions were made for the poor, the less they provided for themselves, and of course became poorer. And, on the contrary, the less was done for them, the more they did for themselves, and became richer.”
― Benjamin Franklin
No cookie-cutter answer for electrostatic filters
There is no cookie cutter answer for the value of electrostatic filters as each brand has different ratings and can be made of different materials.
My experience is that many electrostatic filters are too restrictive (Dusteater, Allergy Gold) and can be hard to clean our if not properly maintained. The exception to the rule is the BoAir 5-Stage filter. It contains no polyester and has a very low air resistance rating. They cost a little more than your standard permanent filter but my customers love them. I have been using them for over 10 years and have received nothing but good feedback from my customers. I think they are made in Florida.
The bottom line with any filter is balancing air resistance versus dust arrestance.
5 1/2 year old thread resurrected by a random Googler...
I can't tell if mark is thanking me for taking the time to reply with my 42 years experience or being hateful?
Was 5 years ago.
When you had 37 yrs exp.
I think original poster is long gone is what he is telling you.
He grew up and became Bill gates
Originally Posted by shaka