Install 3rd A/C
We have a 2010 Fleetwood "Discovery" 40G that we love dearly. However, during a recent trip, it's become clear that having only 2 A/C units simply won't properly cool the rig. The front 2/3 of the ...
Forum Discussion
First things first; check you AC units to make sure they are working properly. Most all AC unit performance can be measured by the temperature differential between the intake air and outlet air. I think the standard is 20 degrees (I may get corrected). I measured mine the other day after I repaired them and they both measured 26 (really good). So if you have the 20 deg difference the unit is working properly. The next thing to check is air flow. If you have the differential but not the proper air flow, well you are still in trouble. They make flow meters for this but I would just open the dump valve and feel the air flow. Compare that flow with someone else s rig. If you have good flow and delta temp the units are good.
To my knowledge there are only two sizes of AC unit's available 13K and 15k. The 2K BTU difference is not much. Nominally only a 15% increase in performance. I don't think you will realize much improvement.
I too am looking at adding a 3rd AC unit. The advantages are much better cooling on those hot days and at night you can shut down the bedroom AC and let the other two cool the coach without having to put up with the bedroom AC unit noise.
Now to your real question, the Generator. My AC units are 15K and draw around 12A when running. What's interesting is the current decreases after a few minutes of running. I am assuming the differential compressor head pressure decreases after a little run time. In any case that's only running 1500w. Start up is much more typically 3 times. So the total AC running watts would be 4500 and a total start up surge of (if they all turned on at the same time of 13500w. Now these are rough numbers there are other things to consider but they are close. Your generator has a max load of 8800w, that's far below the 13500w. The new generators use inverters so I don't think they will take an overload condition like the old non-inverter generators (maybe someone can comment).
I see Dennis has three AC units maybe he can comment on the size of his generator.
For me it's not a problem because I don't camp on the generator very often and using three AC units would only be for a few months in the summer. The rest of the time the existing two AC units would handle everything.
Just food for thought.
To my knowledge there are only two sizes of AC unit's available 13K and 15k. The 2K BTU difference is not much. Nominally only a 15% increase in performance. I don't think you will realize much improvement.
I too am looking at adding a 3rd AC unit. The advantages are much better cooling on those hot days and at night you can shut down the bedroom AC and let the other two cool the coach without having to put up with the bedroom AC unit noise.
Now to your real question, the Generator. My AC units are 15K and draw around 12A when running. What's interesting is the current decreases after a few minutes of running. I am assuming the differential compressor head pressure decreases after a little run time. In any case that's only running 1500w. Start up is much more typically 3 times. So the total AC running watts would be 4500 and a total start up surge of (if they all turned on at the same time of 13500w. Now these are rough numbers there are other things to consider but they are close. Your generator has a max load of 8800w, that's far below the 13500w. The new generators use inverters so I don't think they will take an overload condition like the old non-inverter generators (maybe someone can comment).
I see Dennis has three AC units maybe he can comment on the size of his generator.
For me it's not a problem because I don't camp on the generator very often and using three AC units would only be for a few months in the summer. The rest of the time the existing two AC units would handle everything.
Just food for thought.
