I trust the forum most of the time, but I want to report on my experience which will refute some previous posts that I have read. My RV is a Winnebago Sightseer 35J with two air conditioners, power mangement system with 30 AMP power cord. In 95 degree temps while hooked up to shore power both front and rear AC's worked. I start the front one first and then the rear. They both put out at full power at all times and this was with the electric water heater on as well. I do not think I tried the microwave at the same time, but if I did the power management system most likely would have shut something down as needed. In short, 30 AMPS will power two AC's.
RV: 2008 Winnebago Sightseer 35J
Ford Chassis Teakwood Paint
TOAD:2003 Honda Pilot EXL
BOAT:2002 Mastercraft Maristar 210 VRS
That's why when I was looking for a used unit I only looked at Winnebago's and Bounders. They were the only ones that I knew about that had the EMS installed from the factory. It probably would be great to have a 50 amp system and the full use of all your toys when hooked up to 50 amps, but when you get to a park that only has 30 amp boxes you wind up with problems using even only 2 AC units. If I hook up to a park that has only 50 amp boxes I can still run anything that I want and not worry about the power management.
Our old pace arrow had 2 AC's on a 30 amp system w/EMS. We never had any problems at all. The system would knock the rear AC down if power was needed else where.
Joe & Pascale
Gainesville, FL
08 Safari Simba RD 37PDQ
05 Mazda B2300 dinghy
07 Honda VTX 1300R loaded in the dinghy
It's a lot easier to run 2 A/C units on 30 amps now that the makers have went to the power saving/high efficiency air conditioner units. What used to draw 14-16 amps now draws 10-11 amps.
Way back when even with a EMS a lot of builders used a Polar Cub 7-9K BTU unit back in the bedroom to hold down the amp requirements.
Forester 727 wrote: I trust the forum most of the time, but I want to report on my experience which will refute some previous posts that I have read. My RV is a Winnebago Sightseer 35J with two air conditioners, power mangement system with 30 AMP power cord. In 95 degree temps while hooked up to shore power both front and rear AC's worked. I start the front one first and then the rear. They both put out at full power at all times and this was with the electric water heater on as well. I do not think I tried the microwave at the same time, but if I did the power management system most likely would have shut something down as needed. In short, 30 AMPS will power two AC's.
Your experiance (test) is NOT valid. Even the low amp draw AC units pull about 11 amps total, on hi fan. 22 amps Your Water Heater which you thought was on 120, probably was NOT heating at that time. The W/H does NOT run all the time. So lets add the amps. 22 amps for both AC units. 3 amps for the refer. 1 amp for the Power converter, you are at 26/27 amps which is below the threshold for the EMS system. NOW, I want you to repeat the test, but this time I want you to drain at least 4 gallons of your hot water to make sure the W/H comes on on 120. Run the same setup with both AC units and you will find the EMS will shed either the W/H or Rear AC whichever is first on the shed list. For your Info, the W/H usually draws 10.9 to 12.1 amps depending on the model W/H. So in your first test, IF the W/H was on and heating on 120, the total amp draw just on those 3 appliances would have been about 32 to 34 amps which would have kicked in the EMS system. And this does not take into account the other 120 amp draws--Converter/refer/TV/ etc. The other possibility is your EMS is not functioning correctly. You are correct, 30 amps will run 2 AC units, but NOT without shutting down other Amp loads. You still have to manage your amp Loads even with a 30 amp EMS system if you need 2 AC's to run. Doug
The OP does not mention those 10's of thousands of RV owners who have an older then the OP's 2008 model year rig. As another poster points out, many of us don't even have an EMS system that is capable of shedding excess loads. My EMS was designed in the early '90's and does no load shedding.
With that in mind, I can run both my old fashioned, non-efficient AC's by: 1) running my 6500 Watt genset, both AC's will run when the genset runs; 2)adding a power cord so that I can plug into a 120V outlet on-shore along with my 30A plug that will run my bedroom AC, wiring for that setup is done at the genset; 3)install a new modern load shedding EMS, as well as more efficient ACs - not a trivial expense in an older RV.
What I do to save that expense money is keep my LR AC on low, start it early in the day, park in the shade where possible, keep my awnings out, run a fan or two with the bedroom door open, then about 30 minutes before bedtime, switch to my bedroom AC. By the time I get to bed it's nice an cool in there so I can switch back to the LR AC to run during the night if necessary. Then the biggest thing I do is head North in summer, usually.
So, I'm proactive about cooling, and behave as a load shedding system. I'm happy with that, but would love to have one of those modern load shedding systems.
Jim@HiTek Have shop, will travel! Visit my travel & RV repair blog site.
1994 Fleetwood Bounder
Cummins Diesel, 190HP, 36.5'
Black Rock Lava Park, Nevada
We also have the 35J and have had ZERO problems with 30amps. We've run nearly everything at once and the EMS operates great. Typically the EMS shuts stuff down in proper fashion and is not a problem at all. I don't have to think about what to turn off or worry about power at all, except when my wife wants to blow dry hair for her or our daughter, which is the only time we've ever blown a fuse and that was while microwaving and using a blowdryer. As far as running airconditioners and the hot water heater simultaneously... also no problems at all. With a family of 4 showering, I can guarantee you that we've had that scenario many times.
Doug - unless you have a 35J with the AC on it you're not using the same one as us. My AC after kicking in will draw 7-8 amps according to the EMS panel not the 11 you state.
I share the sentiment of the OP. My 35J runs just fine in 6000 miles and 1 year of lots of use on 30AMP systems. Frankly I don't really care what magic Winnie is using, I just know my works with no issues. If the fridge has to flip to propane while the 2nd AC kicks in and the Micro is on, do I care? I still have cold fridge food, cold AC and warm micro food
2008 Itasca Sunova 35J Class A
1997 TJ Sahara, hard and soft tops and AC
Held together via Roadmaster Falcon 2 tow bar and stopped by US Gear Unified Brake system.
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