Truma Air Condition Unit and battery consumption

[Saxo Appeal]

We are having a Truma A/C fitted to our Swift caravan,

Am I right in saying when you have the A/C powered on, you are limited to what devices you can have on at the same time?

Or have I read this wrong?

The Caravan is also fitted with a Solar Panel

 

[Jcloughie]

The A/C represents a significant draw on whatever your allowance is on any site. So, in an extreme case, if you have a 4 amp pitch and the A/C draws 3.5 amp you can have nothing much else on. Power consumption will need continuous monitoring. A meter can be fitted to make life easier.

John

 

[Saxo Appeal]

Sorry, yes that's right we will be most of the time hooked up with mains on pitches

So this wouldn't be an issue, it would be something to watch for if not connected.

 

[otherclive]

Sorry, yes that's right we will be most of the time hooked up with mains on pitches

So this wouldn't be an issue, it would be something to watch for if not connected.

As JC said it could be an issue if your EHU supply is a lower amperage one. Most British sites supply 16 amps, but some may be less. Continental sites can be quite a bit lower than British ones. If you look at your various systems and equipment you can calculate current draw and plan usage accordingly.
POWER=VOLTS X AMPS. So a 2kw kettle draws 8.3 amps. Not exactly accurate but near enough for caravan purposes.

Does the aircon run off 240 and 12v?

 

[Saxo Appeal]

I'm pretty sure it's the Truma Aventa Compact Plus A/C which is being fitted, although could be wrong, if anyone wants to correct me?

 

[otherclive]

How would we know what you have ordered when there are three options shown. Surely you know what you have ordered.

 

[Saxo Appeal]

I honestly thought I wrote what model it was, how very strange....

It should be the Aventa Compact Plus

 

[Mel]

I may be wrong ( but that has never stopped me before 😀) but I think that when you are ehu the solar panel doesn’t add anything to the amperage coming into the van. You would therefore be limited by the amperage on the bollard.
The solar panel will keep the battery topped up when you are off hook up, but I am not qualified to say if it would keep up with the power being taken by the A/C
Mel

 

[Mr Plodd]

Looking at the specs there is a very significant, but short, start up amperage well over 20 amps and that might cause the supply bollard to trip out if its sensitive.,
A solar panel supplies 12 volts and an A/C unit requires 230 v so your solar panel output has no effect whatsoever.,

 

[ProfJohnL]

Looking at the specs there is a very significant, but short, start up amperage well over 20 amps and that might cause the supply bollard to trip out if its sensitive.,
A solar panel supplies 12 volts and an A/C unit requires 230 v so your solar panel output has no effect whatsoever.,

Mains Miniature circuit breakers (MCB's) and fuses work differently, but both take some time before operating to break the circuit when excess current is detected. This is a designed and useful characteristic, as it reduces nuisance tripping caused by very short term power spikes that can arise on mains circuits. such as when motors start to turn.

I'm confident that Truma would have done their homework on the effects of starting AC compressors on limited power supplies. and when working normally the AC should not trip an MCB or blow a fuse.

 

[ProfJohnL]

Sorry, yes that's right we will be most of the time hooked up with mains on pitches

So this wouldn't be an issue, it would be something to watch for if not connected.

The Truma AC units you have listed do not mention a 12V supply, so it looks as though the units do not require any 12V supply.

There may be some American AC units that can be run from 12V or 24V dc supplies, but I'm not aware of any sold in the UK or Europe

 

[Saxo Appeal]

Does this mean the A/C would only work under mains fixed connection?

And would not be able to run while off grid

 

[Mr Plodd]

Does this mean the A/C would only work under mains fixed connection?

And would not be able to run while off grid

A/C requires 230 volts so requires EHU,
It will NOT work off 12v, so no it won't work when you are off grid.

 

[otherclive]

Mains Miniature circuit breakers (MCB's) and fuses work differently, but both take some time before operating to break the circuit when excess current is detected. This is a designed and useful characteristic, as it reduces nuisance tripping caused by very short term power spikes that can arise on mains circuits. such as when motors start to turn.

I'm confident that Truma would have done their homework on the effects of starting AC compressors on limited power supplies. and when working normally the AC should not trip an MCB or blow a fuse.

Buckman has AC on his caravan and it doesn’t trip the EHU supplies as it kicks in. He’s had a previous one too, so as you say the maker has done their homework. The OPs post above showing the three aircon models gives overcurrent durations.

 

[Buckman]

We have the Truma Comfort and like the other models it can be run on 12v using an inverter, but as pointed out the battery will be flattened very quickly. I think there is a 12v kit for it which is quite expensive and in my opinion not worth it.

We have used the a/c in Spain on a number of occasions where the pitch only had 6amp and we never encountered any issues. We never came across any 4amp sites, but there are probably some lurking around. In the UK the majority of sites seem to be 16amp. Lowest I have come across in the UK is 10amp although again there are probably CLs with lower amp.

In Spain or France on low amp sites the fridge and hot water were run on gas. Obviously we only switched gas for hot water heating in the morning for about an hour and again for about and hour in the evening. If boiling the kettle, we switched off the a/c for the duration. You certainly would not forget to switch it back on.

Bonus is that our caravan has a load monitor fitted which shuts down the hot water or heating if you exceed the limit set by ourselves while using EHU.

 

[Ukdave2002]

If you plan to use an inverter to run a AC unit off grid, remember that power consumption is the same whether its 230v or 12 volt. Rule of thumb whatever the current draw is for 230V multiply it by 20 for the 12 v equivalent.

In other words if the Aventa Compact Plus draws 4.4A at 230V its going to consume some 88A from a 12V source, with a typical 115Ah leisure battery (fully charged) you would get a maximum 1hour 20 mins , or to run continuously at least 1000W's of solar power. In reality you will get less time because inverters are not 100% efficient.

In my mind relying on solar power is not an option.....why? if its hot and sunny you are unlikely to be spending much time in the van, its actually at night when you are trying to sleep in a hot van that AC would, for my mind be the most useful.

 

[Buckman]

If you plan to use an inverter to run a AC unit off grid, remember that power consumption is the same whether its 230v or 12 volt. Rule of thumb whatever the current draw is for 230V multiply it by 20 for the 12 v equivalent.

In other words if the Aventa Compact Plus draws 4.4A at 230V its going to consume some 88A from a 12V source, with a typical 115Ah leisure battery (fully charged) you would get a maximum 1hour 20 mins , or to run continuously at least 1000W's of solar power. In reality you will get less time because inverters are not 100% efficient.

In my mind relying on solar power is not an option.....why? if its hot and sunny you are unlikely to be spending much time in the van, its actually at night when you are trying to sleep in a hot van that AC would, for my mind be the most useful.

We would set the a/c to 20C which was a nice comfortable temperature and the a/c did not have to work hard to keep temperature down. Setting it lower seems a waste of energy plus you end up with a lot of water on your roof from the a/c. Some days unless you are in the sea up top your neck being inside the caravan with a/c is preferable. LOL!