The A/C is not working. Last time this happened the neighborhood A/C
repair guy showed me how to replace the motor start capacitor. He
happened to have one in his truck. I'd just as soon not bother him
again. If I can pull the suspect capacitor and get the specs off it,
where would a guy get a replacement without going the mail order
Assuming lightening struck twice and the reason your A/C stopped working
this time is the same as it was the last time. (But don't bet on it...)
Look for an industrial electrical supply house, or an HVAC supply place.
That's funny, most AC condensing units don't have
start capacitors. It is usually an option though.
You may be referring to the oil filled "run" cap
that is connected to the start winding. A start
capacitor is going to be of the electrolytic type
along with a mechanical or solid state start relay.
Many years ago. Start capacitors are going to be a
high value electrolytic type in a black Bakelite
case along with a potential relay. You will see it
on commercial refrigeration equipment because the
compressor often has to start under a load. Under
ideal conditions, a home AC or refrigerator comp
is going to have time for the pressures to equalize
after shutdown before the thermostat calls for cold.
Last summer I had to remove the factory hard start
PTC thermistor from our office condensing unit after
it shorted. That particular setup did not use a
separate start capacitor. I replaced it with a "Kick
Start" device consisting of a potential relay and a
large electrolytic capacitor. A start capacitor and
relay costs the manufacturer a few dollars more per
unit and you may not think it's much money until you
realize that manufacturer has to purchase a million
of them. Here's a page that shows what I'm referring
The guy has a good site with a lot of information.
OK, just to tie up the loose ends on this one:
1. It turned out the capacitor was fine. I thought it migh be the cap
because the last time that's what it was and the guy that replaced it
told me that it's often the problem. The replacement was one he had
already and I don't know how old it was when we installed it. I
figured if I could get one and install it myself it would be a cheap
enough experiment that it was worth it if I could avoid having to pay
2. I assumed it was a "motor run capacitor" when I went looking for a
replacement and saw references to them. Maybe it wasn't. It's a
capacitor with two sides, one labeled "fan" and the other "therm" with
a common in the center.
3. In the end I ended up calling in my neighbor again. This guy has
been doing heating, A/C, electric and plumbing in the neighborhood for
about 50 years. Nice guy and very helpful and I hate bugging him. He
determined it was low on freon, and charged it. He also checked for
leaks and cleaned out the grill(?) with a hose. I paid him a little
more than what he asked (still a bargain) and gave him a framed photo
of his house with the sunset behind it.
4. I don't know how old the unit is. It was there when we moved in in
'98. I'm going to guess it's about 15 years old.
Just so you know, the terminal marked "herm" means hermetic which
refers to the hermetically sealed welded can compressor. I bet the
wire was yellow for the "herm" and brown for the "fan". The common
terminal could have been just about any color except green.
You may be right, I've been putting in so many hours
lately that everything is running together. My hair
hurts, my toenails itch and my eyeballs are squeaking.
Last service call was over at 8:00pm.
What a shame to hear that the guy has been doing this for 50yrs and
cant find a simple refrigerant leak.
Refrigerant doesnt wear out or go bad. It leaks out. You have a leak.
It will continue to leak and it will continue to cost you money. Not
to mention that it is hard on the equipment running it low on
It is also hard on the environment by depleting our ozone although
that's a whole nother crock of crap.
How small a leak is one supposed to find? One that leaks out not quite
all the refrigerant in 15 years?
Just a few years ago, I was told (IIRC) that A/C techs are finding and
repairing leaks of 4 ounces of refrigerant per year, and that ones
around or less than 2 ounces per year are often too small to find and are
- Don Klipstein ( email@example.com)
I've been using a stop leak made by Cliplight Manufacturing Company
for several years and have had very good luck with it. The stuff is
great for those tiny inaccessible leaks in evaporators.
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