hey guys in today's video i'm going to take you along
on a call that was a low voltage short
and the other one the other day
that i couldn't figure out i went back to um try to re-troubleshoot
it was still working so i just left it alone
but this is one i was able to track down and find out
exactly why it actually burned up
a transformer stay tuned i think you'll find it interesting
it just
wouldn't
come on okay
all right
let me
take a
look here
yeah seems like nothing's
happening can i use
this back door here let's see what you got
all right i'll
be in and out
and i'll use this door
but i'll be out here
nothing seems to be
happening let
me go get
my tool bag power
should have
been run up here
and low voltage
should have
been run here these are these are backwards
that's why this is having to loop around and over the
sharp edge all right let's get
my meter out and see exactly i'm
so i'm expecting to not have low
voltage or something
because nothing
was working got 250
volts i've got zero volts
on my transformer
here it's getting 250 volts
but nothing on the secondary
so my transformer is blown do i not
have
a fuse anywhere
this system has
no low voltage
fuse nothing
nothing all
right as you can
see now forgive me this transformer has a lot
of wires hooked up to it one two three four five six
seven eight ten of them so i have tried to pick out
a transformer that just has these bay connectors
like that one as you see here
so i'm gonna have to put a fuse in this somewhere
because this system
does not have a fuse which seems crazy why would you
not put a low voltage fuse in this thing
somewhere so this red wire that you see right here i'm going
to have to disconnect it and um
find
a way to
fuse it
this is
part of
my high
voltage
this is
going
to go
up here
on 240
other high voltage over
here i'm going to go
on calm these are under
stress right now because of
this and this hot
one i'm going
to have to run
a short little wire
from here to here
and put me a
fuse in there yeah yeah yeah let
me go get a wire so that way i can
do that all right so we just
need to put
a fuse between here
and here i don't have
but one of these left
and get me some more
all right
now let's see
if we can
find a fuse
for the
novices
or or
homeowners
here
is talking
about transformers normally what you think
of are these great big transformers that are either in
your yard or on the power pole
and these basically do the same thing they take a high voltage and
they convert it down into a lower voltage
so this up here is going to be 240 volts and this right
here on the bottom what it produces is our control voltage
or low voltage is 24 volts so um and that
is much safer to run in the house to a thermostat
um line voltage thermostats can cause fires in a
house um i've worked on a few of them
and honestly i think they're a little bit dangerous a low
voltage thermostat may spark a little bit
but it's much less likely to cause a fire so we use low
voltage
Okay
there
goes
the
blower
if y'all
can
hear it
just
took a
second
so what
i'm
doing
here
i'm jumping from red to green
and that's
that's what energizes
my blower i'm jumping from
my red is my hot 24 volts it's hot all the time
and i'm jumping to my other 24 volt control wires
to see if one
of them will blow
my little popper
here am i on a time
delay i know i
just recently
put power to it
but all i see is like
my defrost timer up
there i don't see
a speed up pin normal
delay so i was on a delay okay
because i haven't jumped out
to orange
this is now running in heat
when i jump to y that normally
goes through this defrost control
board and to my contactor it also
goes through any pressure switches
i may have all right next we're
jumping to orange this is our
reversing valve wire
it energizes in cool
that's something
that should happen oh
look at that i did
not hear it when I jumped. Normally you can hear it click.
Let's try that again here in just a
second.
Oh you see that spark?
That tells me there's
a higher amp draw than
normal. All right
we need to look at our reversing valve and wires
and coils and check on it because the reversing
valve wires
watch pop
in the fuse.
There's two
tests you can
do when you
unplug it.
I can now
jump out to orange again and see if it still blows
and that would point to this coil right here and
we can ohm out
this coil and see
if it's something
outrageous it's
not 18 ohms
and that's a black
widow or a brown widow nest all right
my wires for this reversing valve
are these right here and
they're going to come through this bundle
of wires here first let's jump to orange and see what
happens i
can already
tell
that's going
to pop and i
don't want to
stress that
transformer
i just
unplugged orange
to the defrost control
board my it's still
there all right
y'all see here i got
my orange
disconnected
and it popped
my little
popper i got
something
else i need
to try i need
to plug
this back
up and plug
this up
when
there's
when you're
dealing
with a
package
unit like
this
there are basically two sides to your low voltage wires
this one goes to the package unit and this
one goes to your thermostat so i'm going to test in between these two
and see which side is popping
my little popper
y'all hear that all right
that's what it's supposed
to sound like there's nothing
wrong in this system this is not popping my little popper
which tells me my low volt is short
it's somewhere between here
and my thermostat which is not good
an easy fix would be if it's
thermostat and right now we're going to take
the thermostat off the wall and eliminate that and see
if it's a thermostat wire
or the thermostat there
is a chance it can be the sub base
so i'm going
to take
that wire out
of the sub base as
well connected
all right now
let's see if
the thermostat
wire pops
look
at that
didn't do
anything
That
tells me
it is the
thermostat
how about
that it's
It's a thermostat.
Orange
reverse
on
O.
I'm a
little
bit
confused.
They got brown on B,
orange on O, green, yellow.
This thermostat doesn't have
a common, but they got
brown hooked up on B.
Out here, brown is hooked up to blue, which is my common.
So brown is common.
So that would have explained if it had energized in heat,
it would have burned the transformer.
but that's not we found that's not what we found
with our orange wire it was shorting through the
all right i'm gonna have to because of what i found
at the thermostat i'm gonna try something
else no we're
not hooking up common
because it don't have a common
we are hooking our orange
back up he's back
up i was ready
to i'll tell you
what right now
i'm just going
to shut
that back in
there see if it's doing
this and we're going
to jump from red
to orange again
and see what happens
thermostat is on the wall everything's hooked up minus
this brown that they had going to be
and as you see everything's working I
was ready to put on a new thermostat too
I'm looking
for
something
luckily I
dropped
my fuse
somewhere
there it
is we got
one side in
see how
this other side
does it needs
to be tightened
as well all right
there we go okay
I just went inside and turned it on I hear the blower
motor running probably still have a little
bit of a time delay because i just put power to it
a second ago this is how i have my fuse right
here i'm just waiting on this thing
to come on all right i've
been waiting on this for like five
minutes and contactor has not come on i'm beginning
to wonder if that thermostat is programmed
correctly it wasn't wired correctly so it's not out
of the realm of possibilities okay i can tell
by this right here heat off
and cool i have no option for emergency heat but this thermostat
is not meant for a heat pump
and that's why it's not coming on i'm gonna have to replace the
thermostat
anyway
just
heard
it
come
on
i
do
hope
you
enjoyed
the
video
if
you
did
how
about
like
and subscribe riley's in the house watching me see
if y'all can see him can you see riley in the
window we both say thank you for watching i hope you enjoyed
if you did how about like and subscribe
and i'll catch you on the next one
