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Two A/C On Only 30 amps Power

Electrical Amps for A/Cs

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#1 prbrackin

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Posted 07 June 2013 - 07:09 PM

If you run the air conditioners on low do they use less power?

 

I know this is a minor question, but I just don't know.

 

Thanks for any info...

 

PAUL


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#2 wolfe10

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Posted 07 June 2013 - 07:53 PM

Paul,

 

Yes, the A/C draws slightly less power on low.  But, only slightly less.

 

But whether you can run two on 30 amp service depends on a LOT of factors:

 

BTU's or A/C.

Standard efficiency or high efficiency?

What other electrical loads are on (battery charging? water heater? etc).

Is shore power a full 120 VAC or is it down around 110 or even 108 VAC?

 

So, the answer is in ideal conditions with you focused on your electrical system you MAY be able to do it.


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#3 chuckprowse

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Posted 20 June 2013 - 10:10 PM

I sometimes run two ACs on 30amp but I switch or turn off all other loads; refer on gas, batt charger off, no microwave, no Hot water, etc.  And then it sometimes doesn't work because of CG weak breakers or low voltage.

On my Winnie the rear AC would draw power from the genny, I added plugs/receptacles so I could run a separate power cable to the rear AC.


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#4 ClayL

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Posted 21 June 2013 - 12:11 PM

Many motor homes have an energy management system that has the ability shed loads.

On my Winnebago the EMS is made by Intellitec.

 

My motor home is a 30 unit and I can run both ACs at the same time. The EMS prevents the ACs from starting at the same time so the initial current draw surge isn't a problem. If a high current draw appliance like a microwave tries to start when both ACs are running, it first tries shutting the rear AC compressor off. If that isn't enough it will turn the fan off then the refrigerator.

 

That is a very neat feature in my opinion.



 


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#5 grandanny

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Posted 01 July 2013 - 04:15 PM

My MH is a 30 amp unit.  I have recently acquired a 5.5 kw onan generator with two 30 amp breakers.  Only one 30 is currently powering my MH.  I have the other 30 amp line capped off.  Could I run the capped off one to my rear ac?  Then I could run my front ac on the coach circuit and the rear ac on the other 30 amp line?

 

Thanks, I am new to RV.  

 

My MH is a 1989 Safari. 


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#6 vtbigdog

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Posted 01 July 2013 - 08:38 PM

There is a amperage spike when you turn on the AC.  With the first unit running, when you turn on the second unit the sudden increase in amperage could briefly exceed the 30 amp limit and trip the breaker.  In addition, you will have to figure out what else other than your first AC unit is using electricity and subtract that from the 30 amp limit.

 

Paul


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#7 ClayL

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Posted 02 July 2013 - 09:13 AM

My MH is a 30 amp unit.  I have recently acquired a 5.5 kw onan generator with two 30 amp breakers.  Only one 30 is currently powering my MH.  I have the other 30 amp line capped off.  Could I run the capped off one to my rear ac?  Then I could run my front ac on the coach circuit and the rear ac on the other 30 amp line?

 

Thanks, I am new to RV.  

 

My MH is a 1989 Safari. 

I think that the 2nd outlet is 20 amps. It is used for the rear AC in many motor homes. On many it is an automatic switch over but on mine I have to turn a large switch from "Shore Power" to "Generator". That connects the rear AC to the 20 amp generator circuit.


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Clay (WA5NMR), Lee (Wife), katie & Kelli (cats)
Full timer domiciled in SD for 11 years. Now snow birds with a house in western CO
2004 Winnebago Sightseer 35N - Workhorse chassis





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