fridge dilemna

IMO here is your answer;
http://www.sidewinder.com.au/page133.html

Not the cheapest, but with the addition of a 100 to 120 ahr AGM deep cycle battery, you have a fully portable dual battery system that can be fitted into your next vehicle, or removed when its not required.
Price is slightly less than a fully fitted permanent dual battery system.

Mine with a 120 amp hr battery can run my bushman fridge for 3 days and still have 12.1 volts left.

Fitting is easy and comes with all wiring ready to go.
You will need to mount the circuit breaker and run the loom from the battery to the breaker and then to the battery box location.
You will need to be able to securely tie down 35 odd KG of battery and box you wont want that flying around inside the car.

As you are now finding out, buying the fridge is only 1/2 the battle, the other half is finding the energy to run it.

You havent left yourself very much time to solve this and in the very short term your idea of a battery to run your fridge and then be removed for recharge would get you out of the p. o. o. in the short term.
Sitting in the back of a hot car work on 4 to 5 amps an hr for your 60 ltr waeco so you'd probably get around 18 to 20 hrs until you hit 12V (30% remaining charge)out of a 100 amp hr battery and that is very much a guess.

Pete

Two things for now. You are leaving at short notice and it sounds like your cranking battery is on the way out (much greater than 4 hours ).

I travelled with friends who managed pretty well on the one battery but we were travelling enough hours each day to keep it up. You need external source of power like a battery charger for now and think about the other stuff (genny, solar) when you get back.

You can help the fridge along by buying ice along the way which is cheap compared to other solutions. A small bag a day would help heaps.

And try not to let the battery get too low.

Owen

deep cycle 105ah ~$350 . . .(ok)
VSR ~$150 . . . . . . . .(ok)
electrical fitting ~$300 ( think it may be a bit expensive?)
Can you do it yourself?
just the $$ cost of *battery cable*, fuses and lugs.

"I've read that some alternators aren't up to strength to power two batteries"
In your case don't believe that, as it will not be a problem.

You will only need one quality built 100 plus ah Deep Cycle AGM battery

Maîneÿ . . .

The reason your existing cranking battery only lasts 4 hours might be wiring/connections. You might have 12v at the battery but when fridge compressor runs it could drop to below the cutoff point if wiring is not up to scratch.
If you are planning on getting a vehicle which will take 2 batteries easily, then I'd suggest just buying a decent AGM similar and run it as a 2nd battery but not permanently wired or installed into the vehicle (just plonk it in the cargo area and be careful about the terminals).
The sidewinder flyer is good but a little expensive - I used one until I could fit the 2nd batt under the bonnet.

I know it's getting a bit off topic but 80W soular panels are now around the $400 mark, a battery box, a 100Ah battery and one of these would do between power stops..

OBT

Hello

Sounds like your existing vehicle battery has had it. I also have a Waeco CF50 which I can run from a second battery for 24 hours no problem, and the battery isn't anything special - just a cheapie from supercheap auto. I usually set the fridge to 1 degree

My setup consists of a battery box (about $20) in the back of the ute with an isolating switch mounted on it (also about $20). I have a large size cable running from the positive on the battery under the bonnet, through a 20 amp fuse and into the switch on the battery box. Out of the switch onto the positive of the second battery (via another 20 amp fuse in the box) and also to an outlet for the fridge to plug into. The negative of the second battery is connected to the chassis.

I only have the switch closed when the vehicle is running to charge up the second battery. Turn it off when I am at the camping site. I don't know if you would get 48 hours out of it, I would run the engine with the switch closed after 24 hours to charge up the second battery.

In my opinion this is a cheap alternative and from my own experiences works well. I did have one time where after more than 24 hours the fridge low voltage feature had kicked in when the vehicle hadn't been started, so I kicked it over for a while to charge up the battery and kept the fridge running unti we left the next morning

Adam

G'day,

First - read our blog Electricity for Camping which covers a lot of ground you'll find useful, including fridge/battery matters.

Second - If your battery is capable of starting the engine after the fridge has given up, your vehicle battery is fine. If that's the case, there are two probable explanations (interrelated) for why the fridge isn't running for more than 4 hours - as the battery gets down a bit there isn't enough voltage available to the fridge during the current surge while the compressor is starting. This can occur because you have the fridge's low voltage cutout set too high (see the owner manual) and/or you are losing too much voltage in the wiring to the fridge.

If you can't start the engine after running the fridge for 4 hours, and the battery terminals are nice and clean, your vehicle battery is pretty sick.

Assuming the battery is ok:-

Are you running the fridge from a vehicle cigarette lighter socket??? If so, recommend connecting directly to the battery with a fuse (say about 10 amps) inline right at the battery. The losses in the vehicle wiring and the socket itself are too high for this sort of use.

Have you added some extension cable to the fridge??? It's ok to do so but it should be heavy wire - I'd use 6 square mm twin cable for this, and keep it short as possible. (That's NOT 6mm automotive cable, which is 6mm diameter and often is mainly plastic. You need conductors with a cross sectional area of at least 6 square mm of copper.)

The big problem - you want 48 hours operation from you vehicle cranking battery. That's asking a lot if you want to be certain of being able to start the vehicle afterwards. Either you will need a second battery, or for right now, I'd run the engine at fast idle for 30 minutes once or twice a day to top up the vehicle battery.

Batteries - A possibility is to buy an auxilliary battery, and ONLY AFTER the engine has started, connect it in parallel with the vehicle battery. It should be disconnected when the engine is not running otherwise you'll drain both batteries. The aux battery must be a dry type (AGM or gel) if carried inside the vehicle, can be a (cheaper) wet battery if in the engine bay. If it's just to run the fridge and maybe a few lights, a deep cycle battery is preferable, though for a quick and dirty fix, the cheapest Woolworths quality vehicle battery might solve your immediate problem. Personally, for tomorrow's trip I'd burn a little fuel to recharge your present battery, and carry jumper leads just in case.

For now - recommend read the blog, check fridge's low voltage cutout setting and take it to the minimum (probably 10.6V), connect directly (via a fuse) to the battery using minimum practicable length of heavy cable, run engine a couple of times a day while you are away. For the longer term, you will probably want an auxilliary battery, and a suitable controller, but that's in the future!!

Good luck

John

Some very helpful replies, thank you. With time short I've just gone and purchased a 100ah deep cycle. It's sitting in the back of the vehicle connected directly to the Waeco (not connected to vehicle electrics). I've also bought a 30amp 12v battery mains charger. This will get me going immediately and I'll look at long term solutions later.

Is it ok to connect the battery to fridge without an inline fuse (the waeco has a fuse)?

Can I charge the deep cycle battery via mains while it's connected to the fridge?

Is it safe/ok for the deep cycle to have the Waeco permanently on the 'Low' setting (which means it'll drain the battery to around 10v).

It is bad for deep cycle battery life to receive mains charging when battery not very low (i.e. is it best to drain it completely before charging)?

Many thanks for your assistance and advice.

Actually i bought a 105ah not 100ah (not that it probably makes any difference).