Will SoftStarRV really run two ACs on 30amps?

allen456 · 02-16-2021, 07:52 PM

I have the Thor Outlaw, with two AC units. I've seen claims that using SoftStarRV devices (or similar) you can run both ACs on 30amp power. Sounds great but I'd like to hear from anyone who has actually done this and whether there is any downside to it.

Bob Denman · 02-16-2021, 08:12 PM

I don't have an answer for you...

But welcome to the forum anyway!

**16ACE27** · 02-16-2021, 08:24 PM

Quote:

Originally Posted by allen456

I have the Thor Outlaw, with two AC units. I've seen claims that using SoftStarRV devices (or similar) you can run both ACs on 30amp power. Sounds great but I'd like to hear from anyone who has actually done this and whether there is any downside to it.

Isn't you second unit a 5000 BTU unit?

If so you should have no problem running both A/Cs on 30 amps; just not at the same time as your microwave, electric water heater, hair dryer, etc.

JamieGeek · 02-16-2021, 08:35 PM

I put a soft start on my Axis A/C unit. Granted I only have one but I can run the A/C on a normal 15amp circuit from my garage (at least until the garage fridge also plugged in there turns on its compressor).

Bob Denman · 02-16-2021, 09:38 PM

Quote:

Originally Posted by 16ACE27

Isn't you second unit a 5000 BTU unit?

If so you should have no problem running both A/Cs on 30 amps; just not at the same time as your microwave, electric water heater, hair dryer, etc.

I thought he was asking because he has an A Class.
But if it's the C: no problem!

**16ACE27** · 02-16-2021, 10:15 PM

Quote:

Originally Posted by Bob Denman

I thought he was asking because he has an A Class.
But if it's the C: no problem!

The only information provided is he has an Outlaw!

allen456 · 02-17-2021, 02:10 PM

Sorry, I should have been more specific. I have a Class A with two rooftop units, 13,500 BTU each. I'm hoping to hear from someone with a similar AC setup that has installed soft start hardware and run it successfully off of 30 amps.

Bob Denman · 02-17-2021, 02:19 PM

Got it!

There has been a fair amount of discussion along these lines; so somebody us bound to have some practical experience with it...
Are you looking to plug into a 30 amp box at your house?
It might ne easier (and cheaper); to upgrade it to the full 50 amp capacity...

lwmcguire · 02-17-2021, 02:31 PM

i have ran two AC's many times on 30 amps with 120v on the line, factory units

Nothing else can be on including the charger

allen456 · 02-17-2021, 02:38 PM

Were they the 13,500 btu units? Were you using SoftStartRv or some other solution?

thanks, Al

DavidEM · 02-17-2021, 03:21 PM

Starting is one issue, but running current is another. Each 13.5K btu A/Cs will draw up to 15 amps each. There was a recent thread on the Winnie forum about this- https://www.winnieowners.com/forums/...aw-360190.html

The owner had a 13.5 and a 15 Kbtu unit and his 30A circuit breaker would trip out when both were running.

Here is a chart he published of various models of Dometic A/C's starting (LRA) and running (RLA). His draw is about 30 amps total running so no surprise the breaker trips.

David

**16ACE27** · 02-17-2021, 04:08 PM

Quote:

Originally Posted by DavidEM

Starting is one issue, but running current is another. Each 13.5K btu A/Cs will draw up to 15 amps each. There was a recent thread on the Winnie forum about this- https://www.winnieowners.com/forums/...aw-360190.html

The owner had a 13.5 and a 15 Kbtu unit and his 30A circuit breaker would trip out when both were running.

Here is a chart he published of various models of Dometic A/C's starting (LRA) and running (RLA). His draw is about 30 amps total running so no surprise the breaker trips.

David

I have that same setup in my RV; an OEM 15K BTU unit up front and an aftermarket 13.5K BTU unit in the bedroom. I set it up so I can power the bedroom unit separately or on the 30 amp house circuit. Although the starting current may get you it's the running current that puts you right at or over 30 amps total. I have run both A/Cs on the house 30 amp connection with the fridge and WH on gas and I was right at 30 amps on my monitor. Probably not smart to do this for any period of time but if you do you need to check your SP cord and plug periodically for heat - a dirty connection would heat up pretty quickly at 30 amps.
Also, a weak breaker at the SP pole would be a problem and if the compressor on one of the units cycled it may be game over.
The hotter it is outside the harder the A/Cs have to work drawing more current and the more likely it is that you'll trip on running current.

lwmcguire · 02-17-2021, 05:36 PM

Quote:

Originally Posted by 16ACE27

I have that same setup in my RV; an OEM 15K BTU unit up front and an aftermarket 13.5K BTU unit in the bedroom. I set it up so I can power the bedroom unit separately or on the 30 amp house circuit. Although the starting current may get you it's the running current that puts you right at or over 30 amps total. I have run both A/Cs on the house 30 amp connection with the fridge and WH on gas and I was right at 30 amps on my monitor. Probably not smart to do this for any period of time but if you do you need to check your SP cord and plug periodically for heat - a dirty connection would heat up pretty quickly at 30 amps.
Also, a weak breaker at the SP pole would be a problem and if the compressor on one of the units cycled it may be game over.
The hotter it is outside the harder the A/Cs have to work drawing more current and the more likely it is that you'll trip on running current.

I have found all the above to be very important

Running two units always heats up my 30/50 amp adapter and sometimes the receptacle

Typically I have used two to cool down to bearable temperatures and not all day long

Voltage is crucial as well, if your in a campground with low voltage to start with forget it

In my Landmark with a 14.5 and 13.5 I installed a voltage meter at the panel and an amp meter in the panel. It was a 50 amp unit but most campgrounds we visited were 30 amp

In my Tuscany the AirXcel units pull less amps than any of my predecessors at typically 13 to 13.5 which has allowed me to run two more often and the load control panel helps as well not allowing any other loads

Its just not a good idea long term any way you do it without a separate power source back to the pedestal and in my experience I usually had low voltage trying that

plastrd · 02-24-2021, 07:38 PM

Tangentially related but I found I could run my single 13.5k unit on a 15A circuit in a friend's garage without issue by turning the AC fan on manual low so it's already spinning and at slightly lower running amps before the AC compressor kicks in. That way both motors aren't drawing their in-rush current at the exact same time.

edecastro · 02-24-2021, 08:51 PM

Hello,

We have a Thor ACE 30.2, our RV is a 30 AMP and this model come with only one A/C. We installed a second A/C in the Master Bedroom with a SoftStarter in each A/C. The main A/C is 15,000 and the bedroom A/C is a Coleman 13,500 (PowerSaver). We can run both unit in 30 AMPS without any problem. Also we can run both units with the generator.

Jahood · 02-24-2021, 10:26 PM

Join the group RVElectricity and ask Mike Sokol...he has done extensive tests about soft start....bottom line is yes you can run 2 A/C units on 30 amps as long as bother units have the soft start

TurnerFam · 02-25-2021, 12:27 AM

you don't any softstart or anything special for two 13,500w units to run together on 'only' 30amps, as they're not going to be drawing but maybe 20 amps between the two...you have plenty left over for other things...

what people don't consider, though, is the 'other' things that are already running when you try to start both units at a similar time. Yes, the water heater and the battery charger are going to be possible using power at the same time, which is where folks mostly run into 'issues', or tripping breakers, otherwise.

Stay calm, and realize that 30amp is 30amps, no matter 'what' you are powering - whether air conditioners or not. It's not a '30amp' problem, it's trying to do too much all at the same time, which can apply just as easily to 50amp power as well.

we've done it MANY times with no other 'special' help or device or anything, even running floor fans, computer, tv and receiver, all at the same time.

Now, all this can be impacted if the 30amp outlet and breaker you plug into are 'weak' or 'overused' and may be susceptible to tripping too quickly, even when you aren't actually using 30amps. In that case, more than likely changing out the breaker for a new one will solve the problem. I've impressed several campground owner's with this same request. They didn't believe me at first, but once they saw everything working, they changed their minds about people 'not' being able to run two a/cs on 30amps.

bobhhoy · 02-25-2021, 03:49 AM

Quote:

Originally Posted by allen456

I have the Thor Outlaw, with two AC units. I've seen claims that using SoftStarRV devices (or similar) you can run both ACs on 30amp power. Sounds great but I'd like to hear from anyone who has actually done this and whether there is any downside to it.

I’m just guessing, but I think that the answer has to do with the “peak power” required to start the units. If this sum is greater than 30 amps, you breaker at the box will trip.
Of course, if you only start one unit at a time, then you may be able to run both units.

danl61 · 02-25-2021, 03:12 PM

Quote:

Originally Posted by allen456

Sorry, I should have been more specific. I have a Class A with two rooftop units, 13,500 BTU each. I'm hoping to hear from someone with a similar AC setup that has installed soft start hardware and run it successfully off of 30 amps.

Not sure, however there are several 'New' 30amp RV models out there with 2 a/c units. However most I've seen have 11K a/c units not 13.5K like yours. I also do not know why the 'type' of RV would really matter since a 30amp service can be on a class A or class C. Best of luck.

danl61 · 02-25-2021, 03:21 PM

Quote:

Originally Posted by allen456

I have the Thor Outlaw, with two AC units. I've seen claims that using SoftStarRV devices (or similar) you can run both ACs on 30amp power. Sounds great but I'd like to hear from anyone who has actually done this and whether there is any downside to it.

Our friends have a Thor 30.1 that came with a 13.5K a/c. We installed a second a/c unit and a Soft Start on each unit. They are extremely pleased and have no problems running both a/c now. That 13.5K unit can pull close to 25 amps or so when it starts but only about 10-12 while running. The Soft Start units reduce that start up amperage and seems to work well.

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