Re: [VAC] Colman AC

[Jim Dunmyer <jdunmyer@xxxxxxxxxxx>]

Jim,
 You need to find out WHY it's kicking out the breaker. The starting
point, as it is with anything electrical, is to break out a meter. One
thing that many people don't have, but is essential for such
troubleshooting, is a "clampon ammeter". They're available from a number
of sources; Radio Shack has an attachment for a DVM that will do the
job.

First, measure the voltage AT THE UNIT to assure that it's above 110
VAC. If the voltage is down to 108 or so, it's unlikely that the A/C
will work, and it'll do exactly what you describe. If the voltage is
low, you need to find out where you're losing it: at the outlet itself,
a too-small extension cord, or maybe something as simple as a loose
connection in the wiring someplace. (such as at the breaker itself, the
connection at the A/C, or whatever)

If the voltage is above 110 at the A/C, you might check to be certain
you have that at the compressor itself.

It goes without saying that you must measure the voltage with the
compressor running.

Assuming that the voltage is OK, you need to check the current draw on
the compressor. A clampon ammeter is placed around ONE of the wires
feeding a device, you don't need to break the wire like you do with a DC
ammeter. If yours is a 13,000 BTU A/C, it should draw about 15 amps.

There's 2 things that will cause the compressor to draw excessive
current: a bad compressor or a plugged condensor coil. The latter is the
radiator-looking device on the OUTSIDE of the conditioned space. You
must pull the cover (you already have it off for testing, of course) and
check both sides of the condensor coils. Also, check to be sure that
something hasn't brushed against the fins and bent them over; you must
have free air flow over/through the condensor. Make sure the fan is
running. You should also check the evaporator coils to be sure you have
good air flow past it. A plugged filter can cause trouble, but most
people notice when there's no air flow from the grill.

Most conpressors have external starting capacitors, and it's not unheard
of for those to go bad, even while just sitting. Before condemning the
motor, you might change the capacitor(s).

Modern A/C compressors last a long, long time. Problems with an A/C unit
are more likely due to low voltage, plugged up coils, or a bad fan
motor. All of those are easy and cheap to fix. Of course, operating an
A/C on low voltage can cause it to burn up, so it's a wise idea to have
one of those little plugin voltmeters in a prominent place in your rig.
Again, remember that the reading you want is when the A/C is running,
not when there's no load. Many, many campgrounds have inadaquet wiring,
and you're asking for trouble if you run your A/C on low voltage.

                                                  <<Jim>>