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Discussion Starter · #1 ·
Hi all,
I was down Spain in July this year and the heat build-up in the van got very uncomfortable, as I have fitted 2x130 watt solar panels which give off about 14amps in this sort of weather and 4x100ah batteries, would this run a 925watt 240 volt mobile aircon unit through the inverter?
Would the inverter need to be pure sine wave?
Does anyone use mobile A/C and how good are they?

many thanks in advance
Ken
 

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"would this run a 925watt "

No.

Yes I run mobile dash aircon (engine compressor) and mobile roof aircon (from the alternator when really needed). Mains on site when the noise is acceptable (rarely).

Dave
 

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Cheaper to pay for hook up or buy a suitcase genny

your solar panels would take days to recharge batteries

Inverter would cost a bomb to install and if you where lucky would give around 3 to 4 hours use

Alan H
 

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Discussion Starter · #6 ·
Hi Dave,
thanks for that, when I said mobile A/C what I probably should have said was free standing A/C unit.
What voltage is your roof A/C and how many watts is it and how many amps would that take
Ken
 

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925W would pull over 70 amps running at 12V. Heck of a strain on your bateries even if you have 4 of them. You would need some seriously thick cables from batteries to invertor too 8O 8O

Much better off, and safer, using a mains powered one on hook up.

Trevor
 

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Discussion Starter · #9 ·
Hi,
thanks everyone for that, it sounds like the evaporative A/C unit as suggested by AberdeenAngus could be the answer. (including the nakedness).
Does anyone use one of these and how good do they find it please.
Ken
 

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Rest In Peace Mike, 1944-2017.
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Hi

I think you have your answer now so I can ask: and I am not trying to be clever, honest :roll: but why go somewhere so hot that you cannot stand the heat and have to consider running air conditioning? Motorhomes allow you to follow the sun but you don't have to get that far south in July :lol: Or am I missing something... I too hate it when the ambient temperature is very high ( unless it is dry heat) so tend to avoid the places where that happens or at least keep away from them in mid summer.

Although having said that ...it would have been nice to have got too hot in the UK this Summer :evil:

Mike
 

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A/C

Hello,

Depending on the wattage of your portable A/C and the power of your alternator, you could use it on the move. However, as already pointed out would only run for around 3-4 hours and would take a long time for your solar panels to re-charge the batteries.

Mobile A/C units are not as powerful or effecint as split or roof units. Indeed if used in too small a space/room can be even less effecient. More use for spot cooling.

See my other posts regarding portables.

Trev.
 

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Discussion Starter · #12 ·
Hi Mike,
yes you are right, we went down in April and started to make our way back beginning of July, which we usually do as the weather starts to get really hot and the tourists arrive, but I just thought with all that unused power, could it be used to make the van more comfortable, especially for Jasmine, even though she was naked she was still panting and I had to spray her with water.
(The things we do for our dogs.)
Ken
 

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heat in spain air -con

The secret to your problem in Spain in julio? this year has been a hot one and its still hot ,and getting hotter the secret! dont come , we leave about may/june because its too hot where we live and come back sept/oct, but july/agosto are the worst months. try Portugal its cooler and and safer. just had 3 months there and its great, a country of castle's lakes and lots of culture. lots speak french and of course english and they understood our spanish.
 

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Discussion Starter · #15 ·
Hi Silvasurfer,
we love Portugal, spent 4 months touring the coast of Portugal and southern coast of Spain, all wildcamping apart from one week on Faro island which cost about 10 euro, SUPERB.
Ken
 

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My mental arithmatic would suggest that the amps draw allowing for ineficiencies and a depleted battery voltage because of the high amp draw would be closer to 100 amps, so as had been said the answer is NO.
I haven,t yet found any living area air con that is quiet enough to be acceptable. BIG roof vents and shade are probably the best unless you are deaf. One of those insectiside sprays that produce a fine mist filled with water can refresh one,s being.
We had aircon in a Winebago we hired in Oz. We only ever used it to pre-cool the van when we were elsewhere (in the pool). When we returned it was turned OFF. We have not specified living area air-con for our new van but have specified it for the cab, usefull while travelling on the odd occasion.

C.
 

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Discussion Starter · #17 ·
A/C

Hi C,
thanks for that, we do use the water spray and it does help a little.
My van is a hymer and well insulated, if I keep the sun out it takes a long while for the van to get hot inside but once it gets hot its difficult to cool it down again, I just thought if I could run an A/C for say 1 hour it might just lower the temp a bit.
I would be interested to know what the formular is for converting the 240 volt figures, amps/watts etc to 12 volt figures when run through an inverter.
Probably the visit to the pool is the best answer.
many thanks
ken
 

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Hi Ken divide the wattage by the voltage, add about 10% to that figure for inverter losses. ie. 1000watts at 12v= 83.33 amps plus 10%=91.66 amps.

To save calculating I alway assume 10amps at 12v per 100watts as a rule of thumb.

The winnies got two AC units and we find that if we leave the front one on with the doors closed to the bedroom, you can hardly hear it and it cools the bedroom nicely. :D

Olley
 

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Hi ken on a 16amp supply I can run both aircons, The 110volt genny runs everything as its roughly equal to 25amps at 230volts.

My 1800watt inverter won't run either aircons or the M/Wave, the start up current is to high, it immediately trips out. I need a bigger inverter, maybe a yank 110volt one.

Olley
 
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