My whole family has allergy issues.
When we bought this house, I was excited to see a 4" media filter in the return as I thought for sure this would help to control dust and, consequently, help to control allergies.
No such luck.
Last month, after listening to wifey complain about the dust for the last time, it dawned on me, the filter can't work without air moving through it!
So, I set the fan to run 100% and let it go as a test period.
Been about a month, now, and although she won't admit it, there is a lot less dust in the house.
Are there better filtration options? Maybe a better stat that I can setup to run multiple fan speeds or more customizable control schemes?
With the commercial EMS systems i work with, it would be a snap to set up. I'm not really up to date on what is available on the residential market.
I am sure you know more about this than I do, and kinda afraid to even post this reply out of fear of your reaction, but what about a UV light.
I have been told that is the best thing for people with allergy issue.
I've considered a UV light, and may yet put one in.
Does your a/h have variable speed?
A MERV 16 filter is great for alleviating allergy issues.
If you get UV lights make sure to mount them where they shine on the coil. That is where they will do the most good by killing stuff that likes to grow in moist places.
Make sure you have fresh air. Proper filtered ventilation air will go a long way toward keeping allergens down.
No variable speed, unfortunately.
It does have a multiple-speed motor...
I'm thinking some interesting thinks about what I can do with it.....
Google "Genteq Evergreen Motor"
Its a replacement ECM blower motor. I have put on a few and they work great. Have a nice low speed for continuous fan.
I agree with Chuck, you should get an ECM motor to reduce the blower speed (all filters are more effective at slower airflows) and also to reduce your operating costs.
One issue that is often overlooked when it comes to dust are leaky returns. It is imperative that return ducts be absolutely tight to prevent infiltration of dust from building voids and attics. If you have any old 'panned' returns, that's a very leaky arrangement and dust will be readily infiltrated.
As far as UVLs are concerned, do your research carefully before purchasing. Two issues are worthy of note.
#1. The power output of the bulb must be a MINIMUM of 50 micro Watts at 36-inches from the bulb. Anything less is useless. Beware as some manufacturers will tout products with high numbers but they're not at 36-inches. There are many on the market that will produce 180 mW at 36-inches but you need to be knowledgeable when you shop.
#2. Life of the bulb. Most are 10,000 hours or 1-year. There are some that are 20,000 hours or 2-years. It's your choice but I prefer the 2-year models myself.
Also, location of the UVL in the system is important. If there are plastics of any type (including flex duct) within straight line site of the UVL, they'll deteriorate in short order form the UVL rays. UVLs do not kill unless they're directly shining on the offending location. In most systems, you must rely on them to change the DNA of the live organisms as they pass by the bulb. Again, high output from the bulb at 36-inches will insure you get for what you think you're paying.
My whole family has allergy issues.
This is a common thread and I have experienced the same headaches as you. In my home we installed the ECM motors, 4" media filters and went with the Sanuvox R-1700 and Saber Smart UVL's for upstairs. Downstairs was an ECM motor, 4" media filter and the Sanuvox R-4000 with Saber Smart UVL's. This has worked wonders in my home. The addition last year of the Honeywell Pro 8000 t-stats allowed us to control the furnaces at a much more even kill ratio by keeping the fan in a continuos circulation when the system cycles off. Do your homework:cheers on any UVL's before purchase.
Sanuvox.com was a great help to us.
Indoor air quality need a fresh air change every 5-6 hours minimum. A merv 11 air filter removes all pollen, mold spores, and most dust. Pressurize the home with the fresh air to stop most infiltration during calm weather. During wind, recirculate air in home of +merv 11 air filter. Maintain <50%RH on all areas including the air handler. Dry the cooling coil and ducts for several hours every day. I yet to find a home that does not have excess dust on the horizontal surfaces regardless of the filtering system. Wind blows the dust in on windy days and we bring dust on our clothes. A HEPA vac or outside exhaust is a must.
When outdoor dew points are +60^F and a/c loads are light, a whole house dehumidifier is a method of keeping home dry. Also pressurizing the home with fresh air is easily done with 60-100 cfm of fresh air with the better whole house dehumidifiers. The high eff. dehumidifiers control the humidity for less than $1-2 a day. Also upto a merv 14 air filter an be added to the dehumidifier to filter fresh/house air 24/7. Ultra-Aire also has a active carbon/merv 14 option.
Bear Rules: Keep our home <50% RH summer, controls mites/mold and very comfortable.
Provide 60-100 cfm of fresh air when occupied to purge indoor pollutants and keep window dry during cold weather. T-stat setup/setback +8 hrs. saves energy
Use +Merv 10 air filter. -Don't forget the "Golden Rule"
Try balanced ventilation, especially energy recovery ventilation with good filtration (MERV 10 or better). With this method you are exhausting irritants, pollutants and odors being generated in your home, and replacing this bad air with better outdoor air (oxygen), and filtering out triggers like pollen and mold spores. In a matter of hours you will be replacing all of the air in your house, and saving energy in the process.
There are other dynamics that affect dust control in a home such as activity level and how old and how deep the carpet is.
You'll never catch all the dust before it settles somewhere by using a furnace fan. Large particles settle quickly, because mass increases with the cube of the radius whereas the resistance to settling increases only as the square. Compare the settling time for various particle sizes to the time for an air change while running the fan in the air handler on low speed. You'll see that a furnace fan on low speed mostly brings small particles to the filter. Typical furnace filters have a low MERV value and are inefficient at capturing small particles. A filter with a MERV rating > 11 can have an effect and help with allergies, but don't expect too much.
The best approach is to control sources. Infiltration is a significant source of allergens. Constant positive pressure reduces infiltration. Intermittent positive pressure, as with a fresh air ventilation system that runs the fan once in a while, not so much. Balanced air exchange obviously doesn't help reduce infiltration. A constant 70 cfm of HEPA-filtered fresh air into my home gives me very low particle counts. Even so, there is still dust to clean, because infiltration is not the only source of dust and the 70 cfm over the entire house doesn't prevent all infiltration all the time.
-If you won't turn it on then nothing else matters.
You may try a UV light but I would first try to vacuum the house 3 times a week and see if that helps any after a few weeks. You will need a quality vacuum like an Orek or something similar.