Heating, Air Conditioning, Fridge, HVAC/4 Inch MERV 10 Filters


I live in a 60 year old house and the duct system seems to have a lot of particulate matter in it.  When the old electric air cleaner attached to the  furnace ductwork broke there was a noticeable increase in dust and white particulate matter on household surfaces as well as mold growth around air registers.  I will be replacing the furnace with a Carrier Comfort 80 gas furnace and have an option of adding a holding cabinet for a disposable 4 Inch MERV 10 Filter.  I was worried that these filters could either cause a significant decrease in heating/cooling efficiency and/or even possible damage to the furnace as the filter nears the end of its lifetime and gets severely clogged up; evidently they are supposed to last for one year before replacement.  I was wondering what your experience was with these filters: do they cause more potential problems than they are worth?  Thank you for any information.

 You are thinking correctly about the down side to any high density expensive filter.  Since you are talking a $100 the filters do not get changed until past their shelf life and the air flow suffers greatly the longer it is in. I recommend the cheapest 1 inch pleated filter (about $3 )and change it once a month or more.
 That keeps the air flow at its best and ALL the air going through the filter, rather than around a clogged filter

Heating, Air Conditioning, Fridge, HVAC

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john t. borgman


I am in Portland Oregon at Ben's heating 503-233-1779. I work days, so I can only answer early in the day or later in the evening. I only answer public questions for residential equipment. I am very well versed in gas, electric and heat pumps and will only answer residential applications. I have been known the past decade or so, by my employers as the guy you send when no one can figure it out. Trouble shooting is my special. I understand the physics behind air flow, refrigerants and electricity. I understand programmable t-stats, zone controls, economizers, fossil fuel kits and the engineering thought process in the wiring and construction of residential equipment


I was lucky enough to start in this field almost 30 years ago as an installer, for a company that installed the best duct systems I have ever seen, even to this day. The best ,as far as understanding the way air really flows through a duct system, from the return air to the very last supply register . They also had great pride and the duct work was put in, not only to last 50 years, but to look exceptional. Then as I started doing service work, I was again fortunate that I found a 3 year engineering class being put on be a man that was the educational director for the Entire united states for a society called " the Refrigeration Service Engineering Society " And for the next 3 years I schooled at night and practiced what I learned during the day, a great advantage over schooling and then trying to remember it years later.. Versed in duct design manual J heat gain/loss calculations.

Refrigeration Service Engineer's Society

I have 2 inventions that have gone through the process and been recorded at the National Institute of Standards and Technology from start to finish and thus been invited to national innovation workshops by the dept. of Commerce and the dept. of Energy. They are waste heat recovery devices that N.I.S.T approved as valid and am currently looking for marketing partners to get this product into the hands of consumers and make a BIG difference in Energy savings for every Household and Eatery and take a big bite in the the peak hours power consumption that face our Utilities companies.

factory training in Lennox ,Rheem, Ruud ,Trane, Tempstar ,Carrier, Day&Night, Payne, Bryant, Coleman, Intertherm, York, Goodman, Ultra boilers, Unico, Mitsubishi,Sanyo, Taylor, Nicewonger, Navien. Associates degree in Refrigeration Engineering. Certified with Energy Department, Check-me Program, P.T.C.S (performance tested comfort systems ), have N.A.T.E. certifications in gas, a/c & heat pump.

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