Switch setting when towing for 12v fridge.

[tentmonster]

About two weeks ago, whilst I was away, herself announced to me that she had bought a new caravan and when I get home I had to collect it. Its a 2005 Sterling Windward 500. Everything appears to be fine but I have not had a lot of time to fiddle with it - tonight we are leaving for a week in Devon.

Question - when towing what setting do people leave the battery switch on?: 'Car' , ' Caravan' or in the middle. I hooked it up to the car last night and ran the fridge - it seemed to prefer the 'car' setting as when it was on 'caravan' the fridge light kept going on and off.

We're intending to stay over at Gloucester Services tonight and need the fridge working.

 

[Andy-H]

It won't run on the car unless the ignition is on; even when it is, it won't be sufficient to get it cold, just maintain the temperature.
Best bet would be to pre chill it at home either on gas or hook up then flick it over to car whilst driving; possibly chuck a few freezer blocks in there before you head off.

 

[otherclive]

If you will be using the fridge whilst staying overnight I would turn it onto gas, and then back to car battery when you travel onwards. Not forgetting to turn off the gas before you set off.

 

[tentmonster]

Seems that 'car' setting is favorite then. I had the engine running with the manual propped against the accelerator pedal to give just over 1000 rpm. The owner manual for the 'van is useless!

Hopefully I can get the 'van on my neighbour's drive later and I can plug it in for a few hours before we leave. My drive is a bit tight for maneuvering.

 

[otherclive]

Why not run it on gas overnight to cool the fridge down? Then switch to car before setting off? Caravan fridges aren't as powerful as domestic ones so even overnight it may not bring the temperature right down, especially on warm nights they need more time. We tend to put ice blocks into the fridge to aid cooling down when preparing fora trip.

 

[ProfJohnL]

It won't run on the car unless the ignition is on; even when it is, it won't be sufficient to get it cold, just maintain the temperature.
Best bet would be to pre chill it at home either on gas or hook up then flick it over to car whilst driving; possibly chuck a few freezer blocks in there before you head off.

Slightly off topic, but I frequently see statements like the 12v power won't cool the fridge down. I'm sorry but is very misleading. The majority of caravan fridges have the opportunity to run on main 230V ad, LPG, or 12V dc. Each of the different fuels are used to produce heat, and in particular both the mains and 12 elements are simarly rated at about 100 effective Watts. If all three fuels have similar heat outputs, any of the fuels will have a very similar ability to cool the fridge down.

What is different is the length of time the fridge is connected to the different fuel types. As 12V is only available whist connected to a tow vehicle and when the engine is running, due to the relatively short time of journeys compared to the availability of mains power when set up at home or on site, when using 12V it won't have time to cool the fridge down.

So it is usually more effective to pre cool the fridge on mains or gas, but during the journey, 12 V should be more than capable of keeping it properly chilled.

 

[tentmonster]

As I said, I had it running on 12v yesterday with the S socket plugged into the car. Within 10mins the freezer was noticeably colder. The manual (Thetford fridge) does however state that 12v should be used to maintain a low temperature and not to cool it from ambient. I guess what they mean is that 12v is not quite so good.

I'm still setting it to 'car' for our drive to Gloucester this evening and Devon tomorrow. Will the battery charge too as I will probably need the movers when we get there?

 

[otherclive]

Yes if everything is working correctly.

 

[chrisn7]

The fridge should work with the switch in the neutral position. The 'Car' setting, when still hooked up allows the car battery to supply 12v power, but of course care is necessary to avoid a flat car battery. 'Caravan' is for onsite and disconnected from the car.

You won't see the fridge power up in the neutral setting, until the engine has been started and the voltage has risen sufficiently to trigger the fridge relay in the car

 

[WoodlandsCamper]

The fridge should work with the switch in the neutral position.

Why? I understand the neutral position is an 'off' position.

 

[Dustydog]

The fridge should work with the switch in the neutral position.

Why? I understand the neutral position is an 'off' position.

Sir WC.
I'll stand corrected. Are you sure?
My 12S system feeds live power direct to fridge when the engine is running . The 12v switch has nothing to do with the fridge circuit. If it did maybe the fridge could end up running off the leisure battery? ??

 

[WoodlandsCamper]

OK, have re-read the definition of the habitation switch. In 'car' position everything is isolated except fridge.

 

[Anseo]

OK, have re-read the definition of the habitation switch. In 'car' position everything is isolated except fridge.

Woosie moment Sir WC ? :S :cheer: B)