Just wondering if there's a rule-of-thumb on replacing vs. repairing central A/C units?

My home in MA is 8 years old, and has a (rather cheesy looking) "Concord" system installed when it was built. Last night it
stopped cooling - the inside & outside fans run, but no compressor sound, warm air, and the lights dim every 30 seconds or so
like the thermal overload is cycling. I shut it down last night and tried again in the AM with same symptoms.

So I guess the real question is, if it comes down to replacing outside unit + inside coil vs. just replacing the compressor
(do people even do this any more?), what's the best choice? I assume the newer units are more efficient, but how long would
it take to recoup an additional $1000 or $1500 cost?

Eric

On Tue, 17 Jul 2007 12:55:50 -0400, "Eric" wrote:

Just wondering if there's a rule-of-thumb on replacing vs. repairing central A/C units?

My home in MA is 8 years old, and has a (rather cheesy looking) "Concord" system installed when it was built. Last night it
stopped cooling - the inside & outside fans run, but no compressor sound, warm air, and the lights dim every 30 seconds or so
like the thermal overload is cycling. I shut it down last night and tried again in the AM with same symptoms.

So I guess the real question is, if it comes down to replacing outside unit + inside coil vs. just replacing the compressor
(do people even do this any more?), what's the best choice? I assume the newer units are more efficient, but how long would
it take to recoup an additional $1000 or $1500 cost?

Doesn't much sound like a compressor. Likely an electrical
problem or you've sprung a refrigerant leak.

If it worked OK before, you wanna identify the problem.
Call a HVAC technician unless you've got a friend that
can troubleshoot AC properly.

P

"Mit der Dummheit kaempfen Goetter selbst vergebens!"
-Friedrich Schiller

"Eric" wrote in message
g.com...
Just wondering if there's a rule-of-thumb on replacing vs. repairing
central A/C units?

My home in MA is 8 years old, and has a (rather cheesy looking) "Concord"
system installed when it was built. Last night it stopped cooling - the
inside & outside fans run, but no compressor sound, warm air, and the
lights dim every 30 seconds or so like the thermal overload is cycling. I
shut it down last night and tried again in the AM with same symptoms.

So I guess the real question is, if it comes down to replacing outside
unit + inside coil vs. just replacing the compressor (do people even do
this any more?), what's the best choice? I assume the newer units are
more efficient, but how long would it take to recoup an additional $1000
or $1500 cost?

Eric

At 8 years, it is well worth repairing. Could be a simple fix for a couple
of hundred as opposed to a few thousand for a new system. As for the
additional cost of energy efficiency, just run the numbers. $1500 may not
take all that long over the 15 year life of the system., especially at MA
electric rates.

Wouldja beleive it doesn't even have a start cap?

I opened it up for a few quick checks this morning. Motor has 3 leads, one goes to L1, one goes to L2, 3rd goes to L2 via a
40uF cap (which measured 39uF on my multimeter). By L1 and L2 I mean after the contactor, it's a 2-pole so both sides of the
line are switched. The fan of course is after the contactor too and it runs fine, so to me that rules out the contactor.

Wiring diagram shows a start relay and cap with dotted lines and a notation "if equipped", doesn't look like mine is!

Eric

"Meat Plow" wrote in message ...
On Tue, 17 Jul 2007 12:55:50 -0400, Eric wrote:

Just wondering if there's a rule-of-thumb on replacing vs. repairing central A/C units?

My home in MA is 8 years old, and has a (rather cheesy looking) "Concord" system installed when it was built. Last night
it
stopped cooling - the inside & outside fans run, but no compressor sound, warm air, and the lights dim every 30 seconds or
so
like the thermal overload is cycling. I shut it down last night and tried again in the AM with same symptoms.

So I guess the real question is, if it comes down to replacing outside unit + inside coil vs. just replacing the
compressor
(do people even do this any more?), what's the best choice? I assume the newer units are more efficient, but how long
would
it take to recoup an additional $1000 or $1500 cost?

Could be something simple like a start capacitor which would be under $200
to replace. If that's the case and the unit cooled your home well, fix it.

"Eric" wrote in message
g.com...
Just wondering if there's a rule-of-thumb on replacing vs.
repairing central A/C units?

My home in MA is 8 years old, and has a (rather cheesy looking)
"Concord" system installed when it was built. Last night it
stopped cooling - the inside & outside fans run, but no compressor
sound, warm air, and the lights dim every 30 seconds or so like
the thermal overload is cycling. I shut it down last night and
tried again in the AM with same symptoms.

So I guess the real question is, if it comes down to replacing
outside unit + inside coil vs. just replacing the compressor (do
people even do this any more?), what's the best choice? I assume
the newer units are more efficient, but how long would it take to
recoup an additional $1000 or $1500 cost?

Eric

No doubt you have checked for a reset button on the unit. If not,
do so.
It appears you are jumping to conclusions without sufficient
information to make a decision. I'd suggest you get some
professional advice and then make a decision.
Bob-tx

Bob wrote:

"Eric" wrote in message
ng.com...


Just wondering if there's a rule-of-thumb on replacing vs.
repairing central A/C units?

My home in MA is 8 years old, and has a (rather cheesy looking)
"Concord" system installed when it was built. Last night it
stopped cooling - the inside & outside fans run, but no compressor
sound, warm air, and the lights dim every 30 seconds or so like
the thermal overload is cycling. I shut it down last night and
tried again in the AM with same symptoms.

So I guess the real question is, if it comes down to replacing
outside unit + inside coil vs. just replacing the compressor (do
people even do this any more?), what's the best choice? I assume
the newer units are more efficient, but how long would it take to
recoup an additional $1000 or $1500 cost? Eric


No doubt you have checked for a reset button on the unit. If not,
do so.
It appears you are jumping to conclusions without sufficient
information to make a decision. I'd suggest you get some
professional advice and then make a decision.
Bob-tx


It could be something simple to fix, do not jump to conclusions, & if
they condemn the compressor get several Tech's troubleshooting opinions.
The actual operating efficiency of the new higher SEER units depend on a
lot of factors.
All the factors affecting efficiency have to be right to ever get the
rated SEER efficiencies!
http://www.udarrell.com/proper_cfm_b...syste ms.html

- udarrell

--
WISDOM PRINCIPLE DIRECTED EMPOWERMENT COMMUNICATIONS -
THE REAL POLITICAL ISSUES and WISDOM BASED PEOPLE EMPOWERMENT

http://www.udarrell.com/

http://www.udarrell.com/my_pages2.htm
(My Airconditioning Links, Hunting Shooting, Angus Cattle, etc.)

http://www.udarrell.com/principled_a...ju stice.html

http://www.udarrell.com/recognizing_real_enemies.html

http://jesuschristsavior.net/Beatitudes.html

http://www.antiwar.com/ ***

Reality Is Not An Easy Thing To Be Confronted With, or to Accept!

"Eric" wrote in message
g.com...
Just wondering if there's a rule-of-thumb on replacing vs. repairing
central A/C units?

My home in MA is 8 years old, and has a (rather cheesy looking) "Concord"
system installed when it was built. Last night it
stopped cooling - the inside & outside fans run, but no compressor sound,
warm air, and the lights dim every 30 seconds or so
like the thermal overload is cycling. I shut it down last night and tried
again in the AM with same symptoms.

So I guess the real question is, if it comes down to replacing outside
unit + inside coil vs. just replacing the compressor
(do people even do this any more?), what's the best choice? I assume the
newer units are more efficient, but how long would
it take to recoup an additional $1000 or $1500 cost?

Eric


If it actually turns out to be the compressor, replace the complete system.

"Eric" wrote in message
g.com...
Wouldja beleive it doesn't even have a start cap?

I opened it up for a few quick checks this morning. Motor has 3 leads,
one goes to L1, one goes to L2, 3rd goes to L2 via a
40uF cap (which measured 39uF on my multimeter). By L1 and L2 I mean
after the contactor, it's a 2-pole so both sides of the
line are switched. The fan of course is after the contactor too and it
runs fine, so to me that rules out the contactor.

Wiring diagram shows a start relay and cap with dotted lines and a
notation "if equipped", doesn't look like mine is!

Eric


Do you know how completely rediculous that sounds?

"doesn't have a start cap"

"3rd goes to L2 via a 40uF cap (which measured 39uF on my multimeter)"

"Bob" wrote in message
news

"Eric" wrote in message
g.com...
Just wondering if there's a rule-of-thumb on replacing vs.
repairing central A/C units?

My home in MA is 8 years old, and has a (rather cheesy looking)
"Concord" system installed when it was built. Last night it
stopped cooling - the inside & outside fans run, but no compressor
sound, warm air, and the lights dim every 30 seconds or so like
the thermal overload is cycling. I shut it down last night and
tried again in the AM with same symptoms.

So I guess the real question is, if it comes down to replacing
outside unit + inside coil vs. just replacing the compressor (do
people even do this any more?), what's the best choice? I assume
the newer units are more efficient, but how long would it take to
recoup an additional $1000 or $1500 cost?

Eric

No doubt you have checked for a reset button on the unit. If not,
do so.


Reset button is going to make his lights dim every 30 secs???? Oooook!

Do you know how completely ridiculous *that* sounds?

A "start" cap is paired with a relay, is in the circuit when starting, then
when the motor's up to speed the relay opens and current no longer flows
through the cap.

A "run" cap is in the circuit all the time, which is the case with my unit.

Eric

kjpro @ usenet.com wrote in message
...

"Eric" wrote in message
g.com...
Wouldja beleive it doesn't even have a start cap?

I opened it up for a few quick checks this morning. Motor has 3 leads,
one goes to L1, one goes to L2, 3rd goes to L2 via a
40uF cap (which measured 39uF on my multimeter). By L1 and L2 I mean
after the contactor, it's a 2-pole so both sides of the
line are switched. The fan of course is after the contactor too and it
runs fine, so to me that rules out the contactor.

Wiring diagram shows a start relay and cap with dotted lines and a
notation "if equipped", doesn't look like mine is!

Eric


Do you know how completely rediculous that sounds?

"doesn't have a start cap"

"3rd goes to L2 via a 40uF cap (which measured 39uF on my multimeter)"

"EL" wrote in message
ng.com...
Do you know how completely ridiculous *that* sounds?

A "start" cap is paired with a relay, is in the circuit when starting,
then
when the motor's up to speed the relay opens and current no longer flows
through the cap.

A "run" cap is in the circuit all the time, which is the case with my
unit.

Eric


Well, you knew the difference. :-)

Yeah and since the tech came yesterday, now I know it ain't gonna run no matter how many caps you connect to it! :^(

Time for a new system... ugh.

Eric

kjpro @ usenet.com wrote in message ...

"EL" wrote in message
ng.com...
Do you know how completely ridiculous *that* sounds?

A "start" cap is paired with a relay, is in the circuit when starting,
then
when the motor's up to speed the relay opens and current no longer flows
through the cap.

A "run" cap is in the circuit all the time, which is the case with my
unit.

Eric


Well, you knew the difference. :-)