1999 American Eagle AC Control Box
Last August I replaced the original Coleman Mach V AC in our 1999 American Eagle with a Coleman Mach 15. It has worked great since then, and the increased cooling is noticeable.
But a couple of days ago, it quit cooling. Fan works, but no compressor.
Checking out the unit from inside, I found that I'm not getting 12 volts on the yellow wire that controls the compressor.
So I swapped out the Honeywell Thermostat control with the bedroom AC one. But it continued to work fine, and the front one still didn't.
So checking the voltages at the thermostat base plate on the rear unit, I have 12 volts on the Heater, Compressor and Fan connections.
But up front, I have 12v, 5.92v and 12. So only ~6v on the compressor wire. Which of course is the problem.
And FWIW, the 12 volts actually seems to coach battery voltage, since it can sometimes be 12.96, or 13.25. And the 5.92 can be 4.7, or even 1.4v.
So next I checked continuity between the 12v connection on the baseplate, and got a complete open.
OK, so what's in-between? Where does the 12 v on the thermostats coming from. It's not coming from the AC unit, because turning off the breaker still leaves the 12 volts on both units.
So the 12 volts is coming from somewhere else, and is in between the compressor connection on the thermostat and the unit's control box, since I don't have continuity.
American Coach tells me that there is another control box in the rig somewhere, but the location is unclear. First they told me it was in the duct 'under' the AC unit. Then they said that it was in the duct somewhere.
Well, I have a 2" x 10" duct running the length of the coach, connecting the two units. I took off a couple of vents and took photos going in both directions and there's no control box to be seen.
So does anyone have any idea about where this 'mythical' control box is?
There are obviously two of them, since rear unit is still working fine.
Anyone? Anyone?
But a couple of days ago, it quit cooling. Fan works, but no compressor.
Checking out the unit from inside, I found that I'm not getting 12 volts on the yellow wire that controls the compressor.
So I swapped out the Honeywell Thermostat control with the bedroom AC one. But it continued to work fine, and the front one still didn't.
So checking the voltages at the thermostat base plate on the rear unit, I have 12 volts on the Heater, Compressor and Fan connections.
But up front, I have 12v, 5.92v and 12. So only ~6v on the compressor wire. Which of course is the problem.
And FWIW, the 12 volts actually seems to coach battery voltage, since it can sometimes be 12.96, or 13.25. And the 5.92 can be 4.7, or even 1.4v.
So next I checked continuity between the 12v connection on the baseplate, and got a complete open.
OK, so what's in-between? Where does the 12 v on the thermostats coming from. It's not coming from the AC unit, because turning off the breaker still leaves the 12 volts on both units.
So the 12 volts is coming from somewhere else, and is in between the compressor connection on the thermostat and the unit's control box, since I don't have continuity.
American Coach tells me that there is another control box in the rig somewhere, but the location is unclear. First they told me it was in the duct 'under' the AC unit. Then they said that it was in the duct somewhere.
Well, I have a 2" x 10" duct running the length of the coach, connecting the two units. I took off a couple of vents and took photos going in both directions and there's no control box to be seen.
So does anyone have any idea about where this 'mythical' control box is?
There are obviously two of them, since rear unit is still working fine.
Anyone? Anyone?
