Heating, Air Conditioning, Fridge, HVAC/fan speed


Hi John,

Why are there differnt options for blower speeds on a furnace?

We have what seems to be light flow in the home we bought almost two years ago.  The registers at the north end, furthest away from the furnace, have very light flow.  I do know that the lower level was finsihed off after the original construction and iwth the way things were done, i can't believe any modifications were made to the furnace, should there have been a need for them.

Is there any harm looking at the blower speed and if it's wired to low or medium, bumping it up a notch?

The reason I ask is that the forsed air is much less than that in our previous home, it takes much longer time to heat up the place.

We do change the filter regularly since a couple of us have bad allergies and asthma.

Thanks for your thoughts!


 Sorry for the delay, I have been in the emergency room 3 times in the pasty 2 weeks.  It sounds like you nee a service tech out to look at the sizing of your equipment the way your duct work is installed and the way your equipment is set up. Kudo's for the clean filters, that helps any situation.  Look for a company that has N.A.T.E. certified tech's that know what they are looking for.

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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