Mold/Bacteria Protection of an
Air Conditioner Coil
By Ronald G. Fink
The Problem:
g
r
o
u
n
d
f
o
r
m
o
l
d
a
n
d
Cold
gas
is
pumped
through
an
air
conditioner
coil.
A
coil
is
b
a
c
t
e
r
i
a
)
.
A
s
t
h
e
a
i
r
made
up
of
copper
tubing
with
aluminum
fins.
The
cold
gas
c
o
n
d
i
t
i
o
n
e
r
s
y
s
t
e
m
c
y
–
travels
through
the
copper
coil
transmitting
its
low
tempera-
c
l
e
s
o
n
a
n
d
o
f
f
,
t
h
e
a
i
r
ture
to
the
aluminum
fins,
which
are
c
o
n
d
i
t
i
o
n
e
r
g
e
t
s
d
a
m
p
,
now chilled.
cold
and
warm,
this
wet
Aluminum fins transfer cold
d
a
r
k
e
n
v
i
r
o
n
m
e
n
t
i
s
a
p
e
r
f
e
c
t
b
r
e
e
d
i
n
g
g
r
o
u
n
d
f
o
r
m
o
l
d
a
n
d
b
a
c
t
e
r
i
a
.
M
a
n
y
f
o
r
m
s
o
f
m
o
l
d
Mold and bacteria
Copper tubes carry
love
this
atmosphere
in
chilled gas
addition
Listeria,
a
bacterium
that
loves
ice
bins
and
air
con-
d
i
t
i
o
n
e
r
s
y
s
t
e
m
s
.
L
i
s
t
e
r
i
a
i
s
k
n
o
w
n
f
o
r
i
t
s
a
b
i
l
i
t
y
t
o
c
a
u
s
e
l
a
r
g
e
outbreaks of food poisoning in restaurants.
Cross section of a clean
AC coil
Mold
and
bacteria
build
up
on
an
air
conditioner
coil
will
give
you the following indoor air and other problems:
•
Mold Odors
•
Airborne Mold
•
Increased
Allergy Risks
Coil
•
Increased mold colonization of equipment
Condensate pan
Fan/ blower
Filter
•
Increase in
Airborne Bacteria
and associated risk
Return air
Return air from the house is filtered and blown through the
air
conditioner
coil
fins,
which
are
chilled. The
filtered
return
air
is
chilled
by
passing
over
,
under
and
around
the
chilled
•
Decrease in
Air Conditioner
Air Flow
aluminum fins and copper tubing.
•
D
e
c
r
e
a
s
e
i
n
A
i
r
C
o
n
d
i
t
i
o
n
e
r
E
f
fi
c
i
e
n
c
y
•
Reduced equipment lifespan
Cross section of 5 year old Florida ac coil with-
out mold/bacteria protection. 50% air blockage
T
h
e
c
h
i
l
l
e
d
fi
n
s
c
o
n
d
e
n
s
e
t
h
e
m
o
i
s
–
t
u
r
e
o
u
t
o
f
t
h
e
r
e
t
u
r
n
a
i
r
,
m
u
c
h
t
h
e
same
as
a
chilled
glass
of
water
.
The
•
Higher Electric Bills
$
m
o
i
s
t
u
r
e
d
r
i
p
s
o
f
f
t
h
e
fi
n
s
d
o
w
n
t
o
a
collector
or
drip
pan
where
it
is
drained
away as condensate wastewater
.
The UV
-C Solution:
UV
-C Germicidal Lamps
These
are
rapidly
becoming
very
popular
as
an
easy
fix
for
the
air
conditioner
coil
mold
problem.
This
is
one
of
the
most
prevalent
causes
of
the
mold
smell
you
get
when
you
enter
an
air
conditioned
sick
building.
UV
-C
(254nm)
lamps
are
ba-
The
problem
comes
to
play
when
the
filtered,
often
not
so
sically
similar
to
sun
lamps
and
are
typically
only
ef
fective
on
filtered,
return
air
deposits
mold
spores
and
bacteria
on
the
m
i
c
r
o
b
i
a
l
s
t
h
a
t
p
a
s
s
b
y
w
i
t
h
i
n
a
f
e
w
i
n
c
h
e
s
o
f
t
h
e
l
a
m
p
o
r
moist
coil
surfaces
(most
air
conditioner
filters
will
not
filter
areas
where
the
light
is
shining
directly
on
for
extended
pe-
m
o
l
d
s
p
o
r
e
s
a
n
d
b
a
c
t
e
r
i
a
a
n
d
a
c
t
u
a
l
l
y
a
c
t
a
s
a
b
r
e
e
d
i
n
g
riods
of
time,
such
as
the
air
conditioner
coil
(see
article
in
tle
to
no
ef
fect
on
airborne
bacteria,
viruses,
odors
or
VOCs
H
V
A
C
N
e
w
s
–
J
u
n
e
3
0
,
2
0
0
3
a
n
d
A
s
s
o
c
i
a
t
e
d
P
r
e
s
s
unless
very
large
commercial,
heavy-duty
UV
systems
are
1
1/24/03).
Excerpt
from
article:
utilized.
“The
biggest
questions
from
The
key
to
good
UV/air
conditioner
coil
mold
control
is
the
c
o
n
t
r
a
c
t
o
r
s
a
r
e
o
n
p
l
a
c
e
m
e
n
t
,
P
h
a
r
o
s
a
i
d
.
F
o
r
i
n
s
t
a
n
c
e
,
installation.
A
small
air
conditioner
coil
will
require
a
minimum
s
h
o
u
l
d
U
V
G
I
s
b
e
i
n
s
t
a
l
l
e
d
i
n
t
h
e
r
e
t
u
r
n
o
r
s
u
p
p
l
y
?
F
o
r
a
i
r
of
three
UV
lights.
The
geometry
of
the
light
and
the
intensity
s
t
r
e
a
m
c
o
v
e
r
a
g
e
,
t
h
e
s
t
u
d
y
“
D
e
fi
n
i
n
g
t
h
e
E
f
f
e
c
t
i
v
e
n
e
s
s
o
f
U
V
w
i
l
l
d
i
c
t
a
t
e
t
h
e
e
f
f
e
c
t
i
v
e
n
e
s
s
.
R
e
m
e
m
b
e
r
,
o
n
l
y
t
h
e
s
u
r
f
a
c
e
t
h
e
L
a
m
p
s
i
n
s
t
a
l
l
e
d
i
n
C
i
r
c
u
l
a
t
i
n
g
A
i
r
D
u
c
t
w
o
r
k
,
”
f
r
o
m
t
h
e
A
i
r
C
o
n
d
i
t
i
o
n
i
n
g
a
n
d
&
R
e
f
r
i
g
e
r
a
t
i
o
n
T
e
c
h
n
o
l
o
g
y
I
n
s
t
i
t
u
t
e
(
A
R
T
I
)
,
l
i
g
h
t
i
s
s
h
i
n
i
n
g
o
n
w
i
l
l
b
e
t
r
e
a
t
e
d
,
a
n
d
o
n
l
y
u
p
t
o
6
”
t
o
8
”
i
n
d
i
s
–
tance
from
the
bulb.
The
following
are
examples
of
installa-
recommends
placement
in
the
return
side,
with
six
lamps
for
tion:
optimum
effectiveness,
Pharo
pointed
out.
Due
to
space
and
fi
n
a
n
c
i
a
l
c
o
n
s
t
r
a
i
n
t
s
,
h
o
w
e
v
e
r
,
“
M
o
s
t
h
o
m
e
o
w
n
e
r
s
w
o
n
’
t
:
An
eight-year
old
air
conditioner
coil
with
have
that
many
lamps
installed.
So
we
recommend
the
con-
Example
No.
1
t
w
o
b
u
l
b
s
p
r
o
p
e
r
l
y
i
n
s
t
a
l
l
e
d
o
n
t
h
e
i
n
s
i
d
e
,
o
n
e
b
u
l
b
w
a
s
d
e
a
d
.
cu
rre
n
t
i
n
sta
l
l
a
ti
o
n
o
f
a
re
a
l
l
y
g
o
o
d
fil
te
r
,
w
i
th
th
e
U
V
l
a
mp
Note
growth
next
to
the
dead
bulb.
The
other
side
is
clean.
p
l
a
c
e
d
o
v
e
r
t
h
e
i
n
d
o
o
r
c
o
i
l
,
”
P
h
a
r
o
s
a
i
d
.
“
A
i
r
c
o
n
d
i
t
i
o
n
i
n
g
s
y
s
–
N
o
b
u
l
b
s
w
e
r
e
i
n
s
t
a
l
l
e
d
o
n
t
h
e
o
u
t
s
i
d
e
.
A
c
c
o
r
d
i
n
g
l
y
,
o
n
l
y
o
n
e
–
tems are great inventions, but the moist environment (at the
half
of
this
air
conditioner
coil
was
treated.
The
outside
of
the
c
o
i
l
s
)
c
r
e
a
t
e
s
a
m
i
c
r
o
b
i
a
l
b
r
e
e
d
i
n
g
g
r
o
u
n
d
.
”
A
d
d
i
t
i
o
n
a
l
l
y
,
air
conditioner
coil
was
full
of
mold
and
bacteria
blocking
air
when
UV
lamps
are
shining
directly
on
the
coils,
they
are
hit-
fl
o
w
a
n
d
c
r
e
a
t
i
n
g
I
A
Q
p
r
o
b
l
e
m
s
.
T
h
i
s
i
n
s
t
a
l
l
a
t
i
o
n
i
s
o
f
m
i
n
i
m
a
l
ting
a
stationary
target.
When
moving
targets
(VOCs
and
mi-
crobes)
pass
UV
lights,
the
more
sensitive
microbes
may
be
value to the customer
.
d
a
m
a
g
e
d
,
b
u
t
t
h
e
h
a
r
d
i
e
r
o
n
e
s
w
i
l
l
p
a
s
s
u
n
h
a
r
m
e
d
.
U
V
lights,
for
instance,
have
been
found
to
be
better
applied
to
s
h
i
n
e
o
n
t
h
e
i
n
d
o
o
r
c
o
i
l
,
n
o
t
t
o
t
r
y
t
o
c
l
e
a
n
t
h
e
a
i
r
s
t
r
e
a
m
,
p
a
r
–
ticularly
in
residential
and
light
commercial
applications;
air
UV
-C
lights
on
stream
use
requires
intense
UV
saturation.”
an
air
conditioner
coil
are
like
the
sun
shining
on
a
rock
by
a
stream.
No
mold
or
mildew
will
grow
on
the
sunny
rock,
un-
like a shaded rock.
A
ten-year
old
air
conditioner
coil
with
a
UV
Example
No.
2:
b
u
l
b
p
l
a
c
e
d
t
o
o
c
l
o
s
e
t
o
t
h
e
e
n
d
c
o
i
l
.
M
o
s
t
o
f
t
h
e
c
o
i
l
w
a
s
Direct sun – No mold growth
clean,
but
the
25%
over
8”
away
grew
mold
and
bacteria
ac-
tually blocking air flow of 25%.
This installation was of some
value to the client, but not 100%.
UV lamp
No sun – Extensive mold growth
The
main
advantages
to
UV
-C
lights
are
low
cost,
easy
in-
s
t
a
l
l
a
t
i
o
n
a
n
d
e
f
f
e
c
t
i
v
e
n
e
s
s
o
n
s
u
p
p
r
e
s
s
i
n
g
m
o
l
d
/
b
a
c
t
e
r
i
a
growth on the coil that has the light shining on it.
UV
-C
lights
installed
correctly
can
ef
fectively
control
mold
a
n
d
b
a
c
t
e
r
i
a
g
r
o
w
t
h
s
o
n
t
h
e
a
i
r
c
o
n
d
i
t
i
o
n
e
r
c
o
i
l
.
T
h
e
y
h
a
v
e
l
i
t
–
A
small
air
conditioner
coil
with
one
UV
bulb
Example
No.
3:
mounted
in
the
center
.
Only
one-half
of
this
coil
has
UV
pro-
t
e
c
t
i
o
n
a
s
t
h
e
o
u
t
e
r
s
e
c
t
i
o
n
s
h
a
v
e
n
o
U
V
b
u
l
b
s
.
E
x
h
i
b
i
t
3
s
h
o
w
s
h
o
w
t
h
e
l
i
g
h
t
d
o
e
s
n
o
t
g
o
t
h
r
o
u
g
h
t
h
e
c
o
i
l
a
s
t
h
e
geometry of the fins will not permit it.
UV light
A
large residential
AC coil will require 6
Example No. 5:
lamps for a good coverage.
This is an example of an excel-
lent installation.
U
V
–
C
G
e
r
m
i
c
i
d
a
l
L
a
m
p
s
O
n
A
i
r
b
o
r
n
e
M
i
c
r
o
b
e
s
UV
has
the
ability
to
kill
surface
bacteria
that
the
bulb
is
shin-
ing
directly
on
at
a
distance
of
usually
less
than
six
to
eight
inches.
Some
UV
-C
light
companies
state
their
UV
systems
can
kill
99.9%
of
MRSA
bacteria
on
a
single
pass
and
then
reference
an
EP
A
study
.
This
is
very
misleading
as
the
test
was
conducted
on
a
test
unit
of
five
UV
high-energy
lamps,
each
50”
long
in
a
reflective
tunnel,
which
burns
1,100
watts
Light will not pass through coils
of
electricity
. This
is
the
equivalent
of
running
a
hair
dryer
in
your
air
conditioner
24
hours
a
day
.
This
obviously
generates
A
Example
No.
4:
a
lot
of
heat
in
addition
to
burning
a
lot
of
electricity
,
and
the
l
a
r
g
e
r
e
s
i
d
e
n
t
i
a
l
units
cost
thousands
of
dollars.
This
system
is
not
something
c
o
i
l
c
o
u
l
d
r
e
q
u
i
r
e
t
h
e
h
o
m
e
o
w
n
e
r
w
o
u
l
d
i
n
s
t
a
l
l
.
T
h
i
s
i
s
a
n
i
n
d
u
s
t
r
i
a
l
U
V
s
y
s
–
n
i
n
e
U
V
b
u
l
b
s
t
o
t
e
m
;
v
e
r
y
e
x
p
e
n
s
i
v
e
,
h
e
a
v
y
d
u
t
y
s
y
s
t
e
m
s
f
o
r
f
o
o
d
p
r
o
c
e
s
s
i
n
g
p
r
o
v
i
d
e
g
o
o
d
U
V
o
r
m
e
d
i
c
a
l
a
p
p
l
i
c
a
t
i
o
n
s
.
T
h
e
E
P
A
s
t
u
d
y
s
p
e
c
i
fi
c
a
l
l
y
d
i
s
t
i
n
–
p
r
o
t
e
c
t
i
o
n
f
o
r
guishes
this
from
UV
devices
that
are
designed
to
treat
spe-
m
o
l
d
/
b
a
c
t
e
r
i
a
c
i
fi
c
s
u
r
f
a
c
e
s
w
i
t
h
i
n
t
h
e
H
V
A
C
s
y
s
t
e
m
;
i
n
p
a
r
t
i
c
u
l
a
r
,
t
h
e
g
r
o
w
t
h
.
T
h
i
s
w
i
l
l
cooling
coils
and
the
condensate
drain
pan
to
prevent
bio-
add
approximately
l
o
g
i
c
a
l
g
r
o
w
t
h
o
n
t
h
o
s
e
s
u
r
f
a
c
e
s
.
A
s
t
a
n
d
a
r
d
1
2
”
t
o
2
4
”
H
V
A
C
3
0
0
w
a
t
t
s
o
f
h
e
a
t
UV
light
system
installed
in
an
air
conditioner
coil
will
destroy
e
n
e
r
g
y
t
o
t
h
e
a
i
r
mold
and
bacteria
growth
on
the
coil
surface
that
the
UV
light
c
o
n
d
i
t
i
o
n
e
r
s
y
s
–
shines
on.
What
sections
of
the
coil
the
light
does
not
hit
will
tem.
However
,
the
grow
mold
and
bacteria.
The
UV
-C
lights
used
on
an
air
con-
m
o
l
d
/
b
a
c
t
e
r
i
a
p
r
o
–
ditioner
coil
will
provide
little,
if
any
,
airborne
microbial
kill
as
tection
and
subse-
t
h
e
U
V
e
n
e
r
g
y
a
n
d
d
w
e
l
l
o
r
e
x
p
o
s
u
r
e
t
i
m
e
i
s
n
o
t
n
e
a
r
l
y
q
u
e
n
t
a
i
r
fl
o
w
enough
to
kill
fast
moving
airborne
microbials.
UV
technol-
s
a
v
i
n
g
s
w
o
u
l
d
ogy
is
very
simple:
take
a
known
quantity
of
UV
light
and
ex-
m
a
k
e
t
h
i
s
i
n
s
t
a
l
l
a
–
pose
a
surface
or
substance
to
the
light
for
a
specified
period
tion worthwhile.
o
f
t
i
m
e
,
a
n
d
a
p
e
r
c
e
n
t
a
g
e
o
f
t
h
e
m
i
c
r
o
b
i
a
l
s
a
r
e
k
i
l
l
e
d
.
T
h
e
product
of
the
UV
light
intensity
,
multiplied
by
the
time
at
that
i
n
t
e
n
s
i
t
y
,
i
s
t
e
r
m
e
d
“
C
T
V
a
l
u
e
”
.
T
a
b
l
e
s
o
f
C
T
V
a
l
u
e
s
h
a
v
e
AC coils
been
published,
and
are
well
known.
T
o
properly
determine
what
values
to
use,
look
in
one
of
these
tables
and
pick
a
mi-
c
r
o
b
e
,
t
h
e
n
r
e
a
d
t
h
e
c
o
r
r
e
s
p
o
n
d
i
n
g
C
T
V
a
l
u
e
,
a
n
d
d
e
s
i
g
n
t
h
e
N
o
t
e
o
f
c
a
u
t
i
o
n
:
U
n
p
r
o
t
e
c
t
e
d
U
V
–
C
l
a
m
p
s
w
e
r
e
u
s
e
d
f
o
r
this
article.
In
practice,
protected
lamps
should
always
be
u
s
e
d
a
s
U
V
l
a
m
p
s
c
o
n
t
a
i
n
m
e
r
c
u
r
y
,
a
h
a
z
a
r
d
o
u
s
h
e
a
v
y
m
e
t
a
l
k
n
o
w
n
t
o
c
a
u
s
e
h
e
a
l
t
h
p
r
o
b
l
e
m
s
.
A
b
r
o
k
e
n
l
a
m
p
i
n
a
n
UV lamps
HV
AC
system
could
permanently
contaminate
the
system.
Ozone
system
around
that
CT
V
alue.
T
ypical
HV
AC
home
systems
operate
around
2000
cfm
for
a
2,000
sq.
ft.
home.
For
ex-
C
o
n
c
e
r
n
a
b
o
u
t
o
z
o
n
e
a
n
d
H
V
A
C
a
i
r
c
l
e
a
n
i
n
g
d
e
v
i
c
e
s
i
s
o
f
t
e
n
ample,
2,000
cfm
will
have
an
exit
velocity
of
500ft/min,
or
exaggerated.
All
UV
light
lamps
emit
some
ozone.
UV
-C
ger-
8.33
ft/sec.
From
this
value,
the
proper
residence
time
can
micidal
lamps
emit
very
low
levels
way
below
federal
safety
be
evaluated
for
specific
CT
values.
T
ypical
molds
found
in
limits. Many every day items emit ozone such as
h
o
u
s
e
h
o
l
d
s
a
r
e
i
n
th
e
fa
m
i
l
y
.
h
a
s
A
s
p
e
r
g
i
l
l
i
u
s
A
s
p
e
r
g
i
l
l
i
u
s
•
Fluorescent lamps
CT
values
for
a
90%
kill
ranging
from
44,000
to
132,000
uW
–
•
Electric motors
sec/cm
.
spores,
a
common
bacteria,
has
a
Bacillus
subtilis
2
•
Copy machines
CT
value
of
1
1,600
uW
-sec/cm2.
For
example,
we
will
use
•
Electro static air cleaners
the
number
,
because
as
we
will
see,
that
relatively
Bacillus
All
are
within
federal
safety
limits
.
T
o
pass
a
UL,
ETL
or
TUV
l
o
w
n
u
m
b
e
r
w
i
l
l
m
e
a
n
a
r
e
l
a
t
i
v
e
l
y
h
i
g
h
r
e
s
i
d
e
n
c
e
t
i
m
e
.
C
T
t
est
t
hey
m
ust
be
below
.
04
ppm
of
ozone.
O
ut
s
ide
air
is
usu-
values
higher
than
will
require
an
even
longer
resi-
Bacillus
ally higher than this. Example
dence
time.
The
lamps
can
be
placed
at
the
outlet
or
inlet
of
•
.01 ppm ozone becomes detectable to humans
the coils, however
, at this flow rate, you will only have a res-
•
.04 ppm Federal indoor safety limit
i
d
e
n
c
e
t
i
m
e
o
f
0
.
2
4
s
e
c
o
n
d
s
.
T
h
a
t
i
s
o
n
l
y
1
.
7
%
o
f
t
h
e
r
e
–
•
.12 EP
A city safe air limit
quired
14.5
seconds
for
90%
kill.
This
is
not
even
close
to
the
•
.50 ppm smog alert #1
r
e
q
u
i
r
e
d
C
T
V
a
l
u
e
t
o
k
i
l
l
.
I
n
f
a
c
t
,
t
h
i
s
v
a
l
u
e
i
s
s
o
B
a
c
i
l
l
u
s
•
1.0 ppm smog alert #2
s
m
a
l
l
,
t
h
e
U
V
w
i
l
l
h
a
v
e
n
e
x
t
t
o
n
o
e
f
f
e
c
t
o
n
a
n
y
a
i
r
b
o
r
n
e
pathogen.
The
Advanced Oxidation Solution
T
h
e
A
d
v
a
n
c
e
d
O
x
i
d
a
t
i
o
n
P
l
a
s
m
a
w
i
l
l
d
e
s
t
r
o
y
m
o
l
d
a
n
d
b
a
c
t
e
r
i
a
g
r
o
w
t
h
o
n
a
n
a
i
r
c
o
n
d
i
t
i
o
n
e
r
c
o
i
l
a
n
d
t
h
e
a
i
r
fi
l
t
e
r
.
T
h
e
p
l
a
s
m
a
,
being a gas primarily made up of ionized hydro-peroxides, will achieve full coverage as it moves in and around the air con-
ditioner coil fins and through the air filter
, controlling mold and bacteria growth.
Advanced Oxidation
Generator
AC Coils
Ionized
Advanced
Oxidation Plasma
A
c
l
e
a
n
9
E
x
a
m
p
l
e
N
o
.
6
:
y
e
a
r
o
l
d
c
o
i
l
f
r
o
m
a
F
l
o
r
i
d
a
h
o
m
e
t
h
a
t
s
u
r
v
i
v
e
d
3
h
u
r
r
i
–
canes
with
a
total
of
30
days
o
f
p
o
w
e
r
o
u
t
a
g
e
.
A
n
a
d
–
v
a
n
c
e
d
o
x
i
d
a
t
i
o
n
c
e
l
l
w
a
s
p
r
o
p
e
r
l
y
a
n
d
p
r
o
f
e
s
s
i
o
n
a
l
l
y
Fan
Filter
installed.
Silver Nano Coatings
A
new
technology
is
a
silver
nano
coating
on
the
AC
coil
and
drip
pan
to
prevent
microbial
growth.
Copper
and
silver
are
both
good
controllers
of
bacteria
and
mold.
Silver
has
been
u
s
e
d
f
o
r
c
e
n
t
u
r
i
e
s
f
o
r
b
a
c
t
e
r
i
a
c
o
n
t
r
o
l
.
I
n
m
e
d
i
e
v
a
l
t
i
m
e
s
wealthy
families
would
put
a
silver
spoon
in
the
mouth
of
ba-
bies
after
feeding
to
kill
bacteria
and
prevent
food
poisoning.
Hence
the
phrase
“silver
spoon
baby”.
Silver
nano
is
a
prom-
ising
new
possibility
for
low
cost
control
of
bacteria
and
mold.
Silver
Copper
About the author: Ronald G. Fink – President and CEO RGF Environmental Group, Inc.
Mr
. Fink holds a BSME and has been active in UV and Nuclear Energy since the 1960s. He holds numerous patents and authored over
70 articles.
RGF Environmental Group, Inc. founded in 1985 manufactures over 500 products involving UV
,
Advanced Oxidation and Silver Nano C
oatings.
Copyright © RGF 2007