Salem, Oregon Home Inspections

Mark Gagle’s take on Salem, Oregon Heating and Air Conditioning

Mark Gagle, owner of a local Salem, Oregon heating/air and plumbing company; Gagle’s, answered some questions I had on AC.  Specifically I asked about size of the outside unit in relation to the sqft of the home and fenestration (windows and general heat loss) and one-story compared to two-story homes:

“If it is a newer home the windows, doors, insulation and direction facing are
not as critical on homes built from the mid 90’s to date. Anything prior to around
1994, the homes were not as well insulated and the windows and doors are more
of a factor. The most important factors for A.C. are the size of the return air coming back to the furnace/air handler and the location of the supply
registers for the second story of a home
.
If you have a single story home;
650ft. per ton is great. If you have a two story, main floor and upstairs, go
down to 550 to 600 ft. per ton.


What I’m finding out there is a lot of homes
were designed for heating only
, and not for adding A.C. The supply registers for
the upstairs need to be in the ceiling, not the floor! Warm air rises, but cold
air drops. In heating mode, the upstairs works fine because the main floor is
helping to heat the upstairs. But in cooling, unless the registers are in the
ceiling, you won’t cool the upstairs!  On most two story homes, the bedrooms are
all upstairs, and that is were you want cooling.


Another factor is the
thermostat location. It is usually located in a hallway, under or near a return
air grill. That is perfect for a single story home. By drawing air across the
stat going into the R/A [return air] grill you are always getting a accurate reading of the
indoor air temp. But the stat is also the systems sensor, and that is why the
upstairs is always warmer with a two story home. Once again warm air rises, so
all the heat from the main floor ends up upstairs! The same principal is true
for a main floor/basement home. Most two story homes have a 5 to 10 degree
temp. difference between floors.


As for return air duct sizing back to the furnace
for adding A.C.: a 14″ round duct is good for a 2 ton system. A 16″
round is good for a 2 1/2 to 3 ton system. A 18″ round is good for a 3 1/2
to 4 ton system. A 20″ round is good for a 5 ton system. These numbers are
for the max. size for adding A.C. If you don’t move enough air across a A.C.
I.D. coil you will turn it into a block of ice, and have to put the system into
heating to defrost the coil! The round sizes can be converted into rectangular
by multiplying by 3.14 (Pie) That will give you the sq. inches needed for
rectangular ducting.”


Of course this information is above and beyond what a home inspection is about (general visual inspection of systems) but it is still a good thing to know about as it may help me educate my clients more thoroughly.

If you have specific questions about duct sizing and AC/Heating system function refer to a Salem, Oregon Heating and Air contractor, but for questions about general systems, including structure, plumbing, electrical, kitchen appliances, etc….ask me, your Salem Oregon Home Inspector.



Jim Allhiser President/Inspector
http://SalemOregonHomeInspections.com
503.508.4321         jallhiser@perfectioninspectioninc.com

“Always on the cutting edge”

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Have you Inspected your Salem, Oregon home’s GFCI’s lately?

Ground Fault Circuit Interrupters: They are a wonderful safety item that has been required around water since the ’70s and according to the CPSC could prevent over two-thirds of the approximately 300 electrocutions still occurring each year in and around the home. Installation of the device could also prevent thousands of burn and electric shock injuries each year.

GFCI’s continually monitor what goes out, through the hot side and what comes back through the neutral side. Power always flows in a loop so these devices can tell when there is leakage, ie. ground fault.

Ground Fault: Is where the loop of electricity, instead of properly running out the hot side (into the thing that’s plugged in) and back in to the wall on the neutral side, gets shorted.  In other words the power jumps out of the loop / you might get shocked.

That jump/shock is very likely to happen when you are handling your mixer, weed trimmer, curling iron, etc…. that has an electrical problem (internal loose wire maybe) and you reach for something that can allow a direct flow of electrons to go right in to the ground (faucet, water pipe).

"Test Monthly"

So how and how often should you test my GFCI’s? If you look closely on the GFCI it will say, “Test Monthly.” To properly test you should plug something in that you can see is on, like a lamp. Then press the test button. The buttons should ‘pop’ and the lamp should go off. Then reset the button and the lamp should come back on.

If the test doesn’t happen like that, it may be time to replace your hard working GFCIs.

If that is still to much work I would be happy to come and inspect the function of the GFCI’s in your home.