Had our furnace and air ducts cleaned today for the first time in years; could have spun an entire dog from all the embedded hair.  The serviceman tried to upsell me with both a new reusable filter (to get 94% of the airborne substances), and a UV light to be installed in the furnace to get the other 6% worth of mold spores, bacteria and no-seeums.  I bought the filter and also a thorough cleaning of the furnace, but am waiting to decide on the UV light--another $400--until I can determine if this will really improve our indoor air quality.  The house is 1000 sq ft, one dog and two dogwalkers live there.  Any opinions?  One dogwalker (me) has asthma.  I couldn't find any research from a casual googling.

Views: 43772

Reply to This

Replies to This Discussion

UV lights have their place - but in my opinion are ridiculously oversold.  In order to do ANYTHING worthwhile they MUST shine directly on the evaporator coil / drain pan.  Any other location and they do nothing useful.  Only when the shine on the evaporator coil do they have a long enough exposure time to reduce mold and such.

If the UV light is expected to kill mold spores as they fly past in the return duct - it will NEVER happen.  the total dose in the fraction of a second the mold passes thru the light is way to small to damage the mold in any way.  And as far as "killing" mold spores - those are the toughest, most well protected life stage of mold.  It can survive for decades in harsh environments and still be viable.  Why would spores be 'killed' by a fraction of a second of UV?  If that were to happen, then non-metal ducts would not survive the UV light.

I bought the UV lights and found myself replacing the expensive bulbs way more often than one would expect.  I do not recommend the UV component unless there were a realistic possibility that it "might" (emphasize "MIGHT") be of some benefit to an extremely infirm occupant whose doctor recommends such equipment.  Our houses are not hospital isolation wards . . . not even if there is an asthmatic occupant. 

Still, ducts do need to be cleaned periodically.  It's not clear to me why anybody is surprised to learn this to be the case.  The insides of the ducts are inside your house every bit as much as the living room rug.  Vacuuming the rug the does not involve shining an ultraviolet light on the floor.

I did use the 4" pleated filter but went back to a more conventional "rock catcher." The high-MERV filters collect smaller and smaller particles and thus may disturb the air flow and compromise the life of the furnace by making the fan work more than it may have been engineered for and by allowing the heat exchanger to expand excessively because of overheating. 

Don't do UV.

Grab a MERV 13 from filtersfast or something.

RSS

Home Energy Pros

Home Energy Pros was founded by the developers of Home Energy Saver Pro (sponsored by the U.S. Department of Energy,) and brought to you in partnership with Home Energy magazine.  Home Energy Pros is sponsored by the Better Buildings Residential Network.

Latest Activity

David I. Shepherd-Gaw added a discussion to the group Job Board
Thumbnail

JOB: Energy Efficiency Specialist @ Cowlitz PUD

Primarily a position with a residential focus in a great community. Opportunities to expand your…See More
1 hour ago
David I. Shepherd-Gaw joined Diane Chojnowski's group
Thumbnail

Job Board

This group is for posting jobs related to all aspects of the home performance industry including…See More
1 hour ago
John Wilkerson posted a discussion

Aeroseal Machine for Sale

Hello All, We have an Aeroseal SmartSeal system (w/ compressor and plenty of leftover…See More
2 hours ago
Rob Buchanan commented on Jose Macho's blog post Why Don't Homeowners Spend Money on Energy Saving Upgrades??? Blame "Cognitive Biases"
"I think this is an interesting comparison, but I would also want to know whether similar surveys…"
9 hours ago
Bob Blanchette commented on Jose Macho's blog post Why Don't Homeowners Spend Money on Energy Saving Upgrades??? Blame "Cognitive Biases"
"The bigger problem is the way water is billed. Most of the charges are a fixed monthly amount that…"
9 hours ago
John Nicholas replied to Elizabeth Guinn's discussion ERV in need of backflow preventer.
"First,  What is the 24/7 CFM requirement for your house?   Second,  What is the CFM…"
11 hours ago
Chris Dorsi updated an event
Thumbnail

2015 Habitat X Summer National Conference at Big Sky Resort

July 21, 2015 to July 23, 2015
The 2015 Habitat X Summer National Conference will take place at Big Sky Resort, just down the road…See More
19 hours ago
Mike Cerqua replied to Tony Hicks's discussion Slab-on-grade Insulation
" "
21 hours ago

© 2015   Created by Lawrence Berkeley National Laboratory.

Badges  |  Report an Issue  |  Terms of Service