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Default Buzzing from outside AC unit - outside fan is running

Hi - we have a typical home AC system - ours is a Ruud - the model number on
the outside unit is UAKA- 037JAZ. It's been very hot here in Texas - over
100 all day long, but the system is working OK and cooling the house -
plenty of cool air coming out of all the vents - the AC runs a lot these
days, but it always has when it's very hot outside since we've lived here -
I guess that's because it's an older unit (1996) and not as efficient as
some of the newer units. The filter has always been changed regularly.

For several months now, I'm hearing a loud buzzing noise from the outside
unit when it's running - the fan spins OK and there's hot air coming off of
the unit - the noise is nothing that keeps us awake at night, but certainly
noiser than my neighbor's units - they were replaced within the past few
years and they're newer.

Is this kind of noise typical of the older units?? If not, what am I likely
to hear is the main problem from the AC repair guy if the unit goes out and
I need to make a repair call?

I had something on the outside unity replaced a few years ago - I think it
was the start capacitor.

Thanks!


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Default Buzzing from outside AC unit - outside fan is running


"AngryOldWhiteGuy" wrote
in message ...
Hi - we have a typical home AC system - ours is a Ruud - the model number
on the outside unit is UAKA- 037JAZ. It's been very hot here in Texas -
over 100 all day long, but the system is working OK and cooling the
house - plenty of cool air coming out of all the vents - the AC runs a lot
these days, but it always has when it's very hot outside since we've lived
here - I guess that's because it's an older unit (1996) and not as
efficient as some of the newer units. The filter has always been changed
regularly.

For several months now, I'm hearing a loud buzzing noise from the outside
unit when it's running - the fan spins OK and there's hot air coming off
of the unit - the noise is nothing that keeps us awake at night, but
certainly noiser than my neighbor's units - they were replaced within the
past few years and they're newer.

Is this kind of noise typical of the older units?? If not, what am I
likely to hear is the main problem from the AC repair guy if the unit goes
out and I need to make a repair call?

I had something on the outside unity replaced a few years ago - I think it
was the start capacitor.

Thanks!


What you are hearing is the relay , or contactor,inside the condenser. It
receives 24 volts from the blower unit, which energizes it's coil, pulling
in the relay,sending 240 volts to the condenser motor . When these relays
get old or worn, then start making humming or buzzing noises. It's not an
expensive part and with limited electrical experience, can be changed by a
homeowner.




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Default Buzzing from outside AC unit - outside fan is running


"RBM" wrote in message
...

"AngryOldWhiteGuy" wrote
in message ...
Hi - we have a typical home AC system - ours is a Ruud - the model number
on the outside unit is UAKA- 037JAZ. It's been very hot here in Texas -
over 100 all day long, but the system is working OK and cooling the
house - plenty of cool air coming out of all the vents - the AC runs a
lot these days, but it always has when it's very hot outside since we've
lived here - I guess that's because it's an older unit (1996) and not as
efficient as some of the newer units. The filter has always been changed
regularly.

For several months now, I'm hearing a loud buzzing noise from the outside
unit when it's running - the fan spins OK and there's hot air coming off
of the unit - the noise is nothing that keeps us awake at night, but
certainly noiser than my neighbor's units - they were replaced within the
past few years and they're newer.

Is this kind of noise typical of the older units?? If not, what am I
likely to hear is the main problem from the AC repair guy if the unit
goes out and I need to make a repair call?

I had something on the outside unity replaced a few years ago - I think
it was the start capacitor.

Thanks!


What you are hearing is the relay , or contactor,inside the condenser. It
receives 24 volts from the blower unit, which energizes it's coil, pulling
in the relay,sending 240 volts to the condenser motor . When these relays
get old or worn, then start making humming or buzzing noises. It's not an
expensive part and with limited electrical experience, can be changed by a
homeowner.




Thanks RBM - "It is not an expensive part" is excellent news!

"with limited electrical experience" - I've never electrocuted myself - I
guess that qualifies my experience as limited, but I think I'll call a
repair guy to do the work anyway.

Much appreciated!

Joe


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Default Buzzing from outside AC unit - outside fan is running


"AngryOldWhiteGuy" wrote
in message ...

"RBM" wrote in message
...

"AngryOldWhiteGuy"
wrote in message ...
Hi - we have a typical home AC system - ours is a Ruud - the model
number on the outside unit is UAKA- 037JAZ. It's been very hot here in
Texas - over 100 all day long, but the system is working OK and cooling
the house - plenty of cool air coming out of all the vents - the AC runs
a lot these days, but it always has when it's very hot outside since
we've lived here - I guess that's because it's an older unit (1996) and
not as efficient as some of the newer units. The filter has always been
changed regularly.

For several months now, I'm hearing a loud buzzing noise from the
outside unit when it's running - the fan spins OK and there's hot air
coming off of the unit - the noise is nothing that keeps us awake at
night, but certainly noiser than my neighbor's units - they were
replaced within the past few years and they're newer.

Is this kind of noise typical of the older units?? If not, what am I
likely to hear is the main problem from the AC repair guy if the unit
goes out and I need to make a repair call?

I had something on the outside unity replaced a few years ago - I think
it was the start capacitor.

Thanks!


What you are hearing is the relay , or contactor,inside the condenser. It
receives 24 volts from the blower unit, which energizes it's coil,
pulling in the relay,sending 240 volts to the condenser motor . When
these relays get old or worn, then start making humming or buzzing
noises. It's not an expensive part and with limited electrical
experience, can be changed by a homeowner.




Thanks RBM - "It is not an expensive part" is excellent news!

"with limited electrical experience" - I've never electrocuted myself - I
guess that qualifies my experience as limited, but I think I'll call a
repair guy to do the work anyway.

Much appreciated!

Joe


For most people, calling the professionals is advisable. Here is a link to a
typical condenser contactor. It is a double pole relay with a 24 volt
electromagnetic coil:
http://www.ecrater.com/p/6264911/24-...-conditioning#



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Default Buzzing from outside AC unit - outside fan is running

On Jul 18, 3:01*pm, "RBM" wrote:
"AngryOldWhiteGuy" wrote
in ...







"RBM" wrote in message
...


"AngryOldWhiteGuy"
wrote in ...
Hi - we have a typical home AC system - ours is a Ruud - the model
number on the outside unit is UAKA- 037JAZ. *It's been very hot here in
Texas - over 100 all day long, but the system is working OK and cooling
the house - plenty of cool air coming out of all the vents - the AC runs
a lot these days, but it always has when it's very hot outside since
we've lived here - I guess that's because it's an older unit (1996) and
not as efficient as some of the newer units. *The filter has always been
changed regularly.


For several months now, I'm hearing a loud buzzing noise from the
outside unit when it's running - the fan spins OK and there's hot air
coming off of the unit - the noise is nothing that keeps us awake at
night, but certainly noiser than my neighbor's units - they were
replaced within the past few years and they're newer.


Is this kind of noise typical of the older units?? *If not, what am I
likely to hear is the main problem from the AC repair guy if the unit
goes out and I need to make a repair call?


I had something on the outside unity replaced a few years ago - I think
it was the start capacitor.


Thanks!


What you are hearing is the relay , or contactor,inside the condenser. It
receives 24 volts from the blower unit, which energizes it's coil,
pulling in the relay,sending 240 volts to the condenser motor . When
these relays get old or worn, then start making humming or buzzing
noises. It's not an expensive part and with limited electrical
experience, can be changed by a homeowner.


Thanks RBM - "It is not an expensive part" is excellent news!


"with limited electrical experience" - I've never electrocuted myself - I
guess that qualifies my experience as limited, but I think I'll call a
repair guy to do the work anyway.


Much appreciated!


Joe


For most people, calling the professionals is advisable. Here is a link to a
typical condenser contactor. It is a double pole relay with a 24 volt
electromagnetic coil:http://www.ecrater.com/p/6264911/24-...tactor-air-con...



- Hide quoted text -

- Show quoted text -- Hide quoted text -

- Show quoted text -


I agree with calling a professional. Limited electrical experience
aside, limited AC experience might lead to enough confusion to cause
problems. It is good to knkow the likely problem, though, so it can
be priced out, and to avoid the laundry list of possible expensive
fixes.


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Default Buzzing from outside AC unit - outside fan is running


wrote in message
...
On Jul 18, 3:01 pm, "RBM" wrote:

What you are hearing is the relay , or contactor,inside the condenser.
It
receives 24 volts from the blower unit, which energizes it's coil,
pulling in the relay,sending 240 volts to the condenser motor . When
these relays get old or worn, then start making humming or buzzing
noises. It's not an expensive part and with limited electrical
experience, can be changed by a homeowner.


Thanks RBM - "It is not an expensive part" is excellent news!


"with limited electrical experience" - I've never electrocuted myself -
I
guess that qualifies my experience as limited, but I think I'll call a
repair guy to do the work anyway.


Much appreciated!


Joe


For most people, calling the professionals is advisable. Here is a link to
a
typical condenser contactor. It is a double pole relay with a 24 volt
electromagnetic
coil:http://www.ecrater.com/p/6264911/24-...tactor-air-con...



- Hide quoted text -

- Show quoted text -- Hide quoted text -

- Show quoted text -


I agree with calling a professional. Limited electrical experience
aside, limited AC experience might lead to enough confusion to cause
problems. It is good to knkow the likely problem, though, so it can
be priced out, and to avoid the laundry list of possible expensive
fixes.

Absolutely - I didn't wanna have a guy come by and tell me "contactor" and
give me a bill for $500. The part is around $30 - with labor, I'm thinking
that the total should be around $100.

Thanks again, guys!



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Default Buzzing from outside AC unit - outside fan is running

While the repair guy is at your home. Please ask him to clean the
condensor. He should spray on some chemical, onto the outdoor radiator
grille. This will foam up after a minute or two. He should rinse it
all off with a garden hose, and might need a second or third cleaning.
Cleaning the condensor will help with efficiency, and lower your
energy bill.

Do this after replacing the conactor, so he's not kneeling in water.

--
Christopher A. Young
Learn more about Jesus
www.lds.org
..


"AngryOldWhiteGuy"
wrote in message ...

Thanks RBM - "It is not an expensive part" is excellent news!

"with limited electrical experience" - I've never electrocuted
myself - I
guess that qualifies my experience as limited, but I think I'll call a
repair guy to do the work anyway.

Much appreciated!

Joe



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Default Buzzing from outside AC unit - outside fan is running

Fair retail price, too. Many AC units use single pole contactor. For
when the unit has a crankcase heater.

--
Christopher A. Young
Learn more about Jesus
www.lds.org
..


"RBM" wrote in message
...

For most people, calling the professionals is advisable. Here is a
link to a
typical condenser contactor. It is a double pole relay with a 24 volt
electromagnetic coil:
http://www.ecrater.com/p/6264911/24-...-conditioning#




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Default Buzzing from outside AC unit - outside fan is running


"Stormin Mormon" wrote in message
...
While the repair guy is at your home. Please ask him to clean the
condensor. He should spray on some chemical, onto the outdoor radiator
grille. This will foam up after a minute or two. He should rinse it
all off with a garden hose, and might need a second or third cleaning.
Cleaning the condensor will help with efficiency, and lower your
energy bill.

Do this after replacing the conactor, so he's not kneeling in water.

--
Christopher A. Young
Learn more about Jesus
www.lds.org
.

I've actually cleaned the condensor coils myself - I took apart the sheet
metal pieces surrounding the coils and hosed them off real good - I think I
actually sprayed some kitchen cleaner \ degreaser on the coils after I hosed
them off the first time, and then after spraying them down with the
cleanser, hosed them off again. When I started, there was an unbelievable
amount of grass clippings and other, accumulated gunk in the coils.

Thanks for the suggestion !!


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Default Buzzing from outside AC unit - outside fan is running

On Jul 18, 12:03*pm, "AngryOldWhiteGuy"
wrote:
Hi - we have a typical home AC system - ours is a Ruud - the model number on
the outside unit is UAKA- 037JAZ. *It's been very hot here in Texas - over
100 all day long, but the system is working OK and cooling the house -
plenty of cool air coming out of all the vents - the AC runs a lot these
days, but it always has when it's very hot outside since we've lived here -
I guess that's because it's an older unit (1996) and not as efficient as
some of the newer units. *The filter has always been changed regularly.

For several months now, I'm hearing a loud buzzing noise from the outside
unit when it's running - the fan spins OK and there's hot air coming off of
the unit - the noise is nothing that keeps us awake at night, but certainly
noiser than my neighbor's units - they were replaced within the past few
years and they're newer.

Is this kind of noise typical of the older units?? *If not, what am I likely
to hear is the main problem from the AC repair guy if the unit goes out and
I need to make a repair call?

I had something on the outside unity replaced a few years ago - I think it
was the start capacitor.

Thanks!


When was the last time anyone lubricated your condenser fan motor?


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Default Buzzing from outside AC unit - outside fan is running


"Molly Brown" wrote in message
...
On Jul 18, 12:03 pm, "AngryOldWhiteGuy"
wrote:
Hi - we have a typical home AC system - ours is a Ruud - the model number
on
the outside unit is UAKA- 037JAZ. It's been very hot here in Texas - over
100 all day long, but the system is working OK and cooling the house -
plenty of cool air coming out of all the vents - the AC runs a lot these
days, but it always has when it's very hot outside since we've lived
here -
I guess that's because it's an older unit (1996) and not as efficient as
some of the newer units. The filter has always been changed regularly.

For several months now, I'm hearing a loud buzzing noise from the outside
unit when it's running - the fan spins OK and there's hot air coming off
of
the unit - the noise is nothing that keeps us awake at night, but
certainly
noiser than my neighbor's units - they were replaced within the past few
years and they're newer.

Is this kind of noise typical of the older units?? If not, what am I
likely
to hear is the main problem from the AC repair guy if the unit goes out
and
I need to make a repair call?

I had something on the outside unity replaced a few years ago - I think it
was the start capacitor.

Thanks!


When was the last time anyone lubricated your condenser fan motor?

Probably when it was built, and sealed at the factory


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Default Buzzing from outside AC unit - outside fan is running

On Sun, 18 Jul 2010 19:36:59 -0400, "RBM" wrote:


"Molly Brown" wrote in message
...
On Jul 18, 12:03 pm, "AngryOldWhiteGuy"
m wrote:
Hi - we have a typical home AC system - ours is a Ruud - the model number
on
the outside unit is UAKA- 037JAZ. It's been very hot here in Texas - over
100 all day long, but the system is working OK and cooling the house -
plenty of cool air coming out of all the vents - the AC runs a lot these
days, but it always has when it's very hot outside since we've lived
here -
I guess that's because it's an older unit (1996) and not as efficient as
some of the newer units. The filter has always been changed regularly.

For several months now, I'm hearing a loud buzzing noise from the outside
unit when it's running - the fan spins OK and there's hot air coming off
of
the unit - the noise is nothing that keeps us awake at night, but
certainly
noiser than my neighbor's units - they were replaced within the past few
years and they're newer.

Is this kind of noise typical of the older units?? If not, what am I
likely
to hear is the main problem from the AC repair guy if the unit goes out
and
I need to make a repair call?

I had something on the outside unity replaced a few years ago - I think it
was the start capacitor.

Thanks!


When was the last time anyone lubricated your condenser fan motor?

Probably when it was built, and sealed at the factory

Last time mine buzzed I just tightened the loose screws on the housing
and everything was quiet again. That was about 10 years ago - the AC
is about 35 years old.
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Default Buzzing from outside AC unit - outside fan is running

On 7/18/2010 5:15 PM, AngryOldWhiteGuy wrote:
"Stormin wrote in message
...
While the repair guy is at your home. Please ask him to clean the
condensor. He should spray on some chemical, onto the outdoor radiator
grille. This will foam up after a minute or two. He should rinse it
all off with a garden hose, and might need a second or third cleaning.
Cleaning the condensor will help with efficiency, and lower your
energy bill.

Do this after replacing the conactor, so he's not kneeling in water.

--
Christopher A. Young
Learn more about Jesus
www.lds.org
.

I've actually cleaned the condensor coils myself - I took apart the sheet
metal pieces surrounding the coils and hosed them off real good - I think I
actually sprayed some kitchen cleaner \ degreaser on the coils after I hosed
them off the first time, and then after spraying them down with the
cleanser, hosed them off again. When I started, there was an unbelievable
amount of grass clippings and other, accumulated gunk in the coils.

Thanks for the suggestion !!



Most home owners don't realize that they must turn off the AC when
cutting the grass. The condensing (outdoor) unit is like a giant
vacuum cleaner and will inhale a lot of dirt and dust. I always try
to get customers to cut back the hedges from the unit and lay a bed
of pea gravel around the base of the unit and keep the pine straw
and other landscape fill away from the condenser.

TDD
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Default Buzzing from outside AC unit - outside fan is running

On 7/18/2010 2:03 PM, AngryOldWhiteGuy wrote:
Hi - we have a typical home AC system - ours is a Ruud - the model number on
the outside unit is UAKA- 037JAZ. It's been very hot here in Texas - over
100 all day long, but the system is working OK and cooling the house -
plenty of cool air coming out of all the vents - the AC runs a lot these
days, but it always has when it's very hot outside since we've lived here -
I guess that's because it's an older unit (1996) and not as efficient as
some of the newer units. The filter has always been changed regularly.

For several months now, I'm hearing a loud buzzing noise from the outside
unit when it's running - the fan spins OK and there's hot air coming off of
the unit - the noise is nothing that keeps us awake at night, but certainly
noiser than my neighbor's units - they were replaced within the past few
years and they're newer.

Is this kind of noise typical of the older units?? If not, what am I likely
to hear is the main problem from the AC repair guy if the unit goes out and
I need to make a repair call?

I had something on the outside unity replaced a few years ago - I think it
was the start capacitor.

Thanks!



The buzzing is caused by a bit of rust or believe or not an insect
caught in the armature of the contactor. When the contactor pulls
in, it will buzz if the flat surfaces of the electromagnet is in
any way interfered with. Sometimes a simple whack with a screwdriver
handle will clear the debris and the buzzing will go away. Cleaning
the contactor with contact cleaner or heaven forbid, WD-40 will often
flush out the bugs, dirt and rust.

TDD
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Default Buzzing from outside AC unit - outside fan is running

On Sun, 18 Jul 2010 14:15:29 -0500, "AngryOldWhiteGuy"
wrote:


"RBM" wrote in message
...

"AngryOldWhiteGuy" wrote
in message ...
Hi - we have a typical home AC system - ours is a Ruud - the model number
on the outside unit is UAKA- 037JAZ. It's been very hot here in Texas -
over 100 all day long, but the system is working OK and cooling the
house - plenty of cool air coming out of all the vents - the AC runs a
lot these days, but it always has when it's very hot outside since we've
lived here - I guess that's because it's an older unit (1996) and not as
efficient as some of the newer units. The filter has always been changed
regularly.

For several months now, I'm hearing a loud buzzing noise from the outside
unit when it's running - the fan spins OK and there's hot air coming off
of the unit - the noise is nothing that keeps us awake at night, but
certainly noiser than my neighbor's units - they were replaced within the
past few years and they're newer.

Is this kind of noise typical of the older units?? If not, what am I
likely to hear is the main problem from the AC repair guy if the unit
goes out and I need to make a repair call?

I had something on the outside unity replaced a few years ago - I think
it was the start capacitor.

Thanks!


What you are hearing is the relay , or contactor,inside the condenser. It
receives 24 volts from the blower unit, which energizes it's coil, pulling
in the relay,sending 240 volts to the condenser motor . When these relays
get old or worn, then start making humming or buzzing noises. It's not an
expensive part and with limited electrical experience, can be changed by a
homeowner.




Thanks RBM - "It is not an expensive part" is excellent news!

"with limited electrical experience" - I've never electrocuted myself - I
guess that qualifies my experience as limited,


That qualifies my experience as limited, you say.

Even more limited than if you had electrocuted yourself.

Now that would have been an experience

but I think I'll call a
repair guy to do the work anyway.

Much appreciated!

Joe




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Default Buzzing from outside AC unit - outside fan is running

On Sun, 18 Jul 2010 20:03:34 -0400, wrote:

On Sun, 18 Jul 2010 19:36:59 -0400, "RBM" wrote:


"Molly Brown" wrote in message
...
On Jul 18, 12:03 pm, "AngryOldWhiteGuy"
wrote:
Hi - we have a typical home AC system - ours is a Ruud - the model number
on
the outside unit is UAKA- 037JAZ. It's been very hot here in Texas - over
100 all day long, but the system is working OK and cooling the house -
plenty of cool air coming out of all the vents - the AC runs a lot these
days, but it always has when it's very hot outside since we've lived
here -
I guess that's because it's an older unit (1996) and not as efficient as
some of the newer units. The filter has always been changed regularly.

For several months now, I'm hearing a loud buzzing noise from the outside
unit when it's running - the fan spins OK and there's hot air coming off
of
the unit - the noise is nothing that keeps us awake at night, but
certainly
noiser than my neighbor's units - they were replaced within the past few
years and they're newer.

Is this kind of noise typical of the older units?? If not, what am I
likely
to hear is the main problem from the AC repair guy if the unit goes out
and
I need to make a repair call?

I had something on the outside unity replaced a few years ago - I think it
was the start capacitor.

Thanks!


When was the last time anyone lubricated your condenser fan motor?


It's not the fan motor. Even if it needed lubrication, it woudln't
make the noise he dscribes.

Probably when it was built, and sealed at the factory

Last time mine buzzed I just tightened the loose screws on the housing
and everything was quiet again. That was about 10 years ago - the AC
is about 35 years old.


A very good idea. And something one with little experience can try
first. He can put his hand on the panels and see if any is vibrating.

If not that, it's the contactor and I thind Dufas has some good ideas.
Keep that up, Dufas, and you'll lose your right to your name.
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On Sun, 18 Jul 2010 22:24:37 -0500, The Daring Dufas wrote:

The buzzing is caused by a bit of rust or believe or not an insect
caught in the armature of the contactor.


nods



Heard this sound many, many times. Doesn't take much rust on the
laminated core of the contactor or the plunger to make them hum.



--
Altopia.com $12/m 10 unlimited connections
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"Meat Plow" wrote in message
news
On Sun, 18 Jul 2010 22:24:37 -0500, The Daring Dufas wrote:

The buzzing is caused by a bit of rust or believe or not an insect
caught in the armature of the contactor.


nods



Heard this sound many, many times. Doesn't take much rust on the
laminated core of the contactor or the plunger to make them hum.


Thanks for all of the great information guys!


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Default Buzzing from outside AC unit - outside fan is running

Squealing, not buzzing.

--
Christopher A. Young
Learn more about Jesus
www.lds.org
..


When was the last time anyone lubricated your condenser fan motor?

Probably when it was built, and sealed at the factory



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Default Buzzing from outside AC unit - outside fan is running

On 7/19/2010 7:37 AM, Meat Plow wrote:
On Sun, 18 Jul 2010 22:24:37 -0500, The Daring Dufas wrote:

The buzzing is caused by a bit of rust or believe or not an insect
caught in the armature of the contactor.


nods



Heard this sound many, many times. Doesn't take much rust on the
laminated core of the contactor or the plunger to make them hum.




There was a whole article in an EE magazine about converting AC
contactors to DC to prevent the buzzing which can cause overheating
of the contactor coil.

TDD


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Default Buzzing from outside AC unit - outside fan is running

On Mon, 19 Jul 2010 10:49:54 -0500, The Daring Dufas wrote:

On 7/19/2010 7:37 AM, Meat Plow wrote:
On Sun, 18 Jul 2010 22:24:37 -0500, The Daring Dufas wrote:

The buzzing is caused by a bit of rust or believe or not an insect
caught in the armature of the contactor.


nods



Heard this sound many, many times. Doesn't take much rust on the
laminated core of the contactor or the plunger to make them hum.




There was a whole article in an EE magazine about converting AC
contactors to DC to prevent the buzzing which can cause overheating of
the contactor coil.

TDD


Makes sense. Gap causes eddy currents I suppose. Same things apply for
transformer/inductor core design.





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Default Buzzing from outside AC unit - outside fan is running

RBM wrote:
"AngryOldWhiteGuy" wrote
in message ...

Hi - we have a typical home AC system - ours is a Ruud - the model number
on the outside unit is UAKA- 037JAZ. It's been very hot here in Texas -
over 100 all day long, but the system is working OK and cooling the
house - plenty of cool air coming out of all the vents - the AC runs a lot
these days, but it always has when it's very hot outside since we've lived
here - I guess that's because it's an older unit (1996) and not as
efficient as some of the newer units. The filter has always been changed
regularly.

For several months now, I'm hearing a loud buzzing noise from the outside
unit when it's running - the fan spins OK and there's hot air coming off
of the unit - the noise is nothing that keeps us awake at night, but
certainly noiser than my neighbor's units - they were replaced within the
past few years and they're newer.

Is this kind of noise typical of the older units?? If not, what am I
likely to hear is the main problem from the AC repair guy if the unit goes
out and I need to make a repair call?

I had something on the outside unity replaced a few years ago - I think it
was the start capacitor.

Thanks!



What you are hearing is the relay , or contactor,inside the condenser. It
receives 24 volts from the blower unit, which energizes it's coil, pulling
in the relay,sending 240 volts to the condenser motor . When these relays
get old or worn, then start making humming or buzzing noises. It's not an
expensive part and with limited electrical experience, can be changed by a
homeowner.





In my experience, when the relay is located outdoors and not well sealed
from the environment, what happens is that the D shaped copper "shading
coil" at the armkature end of the relay coil corrodes into nothingness
and can no longer serve its function of creating an out of phase AC
magnetic field to prevent the buzzing of the relay armature.

(More than you needed to know, huh?)

Jeff

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