Choosing the right RV fridge
When it comes to choosing the right fridge for your RV, there's more to it than ensuring chilled wine at happy hour...
debate about what turns a good caravan into a great one. However, one thing’s for sure: when it comes to comfort and liveability, the right fridge is all-important.
A good bed might make for restful nights, sensible storage design can avoid packing hassles and the size of the shower does directly relate to the likelihood of you cleaning yourself without drowning anyone in the dinette.
But the fridge is about keeping your beer cold, your milk fresh, and your butter from turning into a pool of gloop dripping from the second shelf. An inadequate fridge impacts on every aspect of your time away.
This is one time when size does matter, though it’s not quite that simple. First, there’s the problem of which of the two types of fridge is best – a three-way absorption (240V/12V/gas) or compressor (240V/12V) unit. How the fridge works dictates the type of power supply it requires, and the issue of power supply reflects, to some extent, the type of caravanning you enjoy.
If you plan to be out in the sunny bush with a van with ample solar panels, you’d consider a 12V compressor fridge – they operate on a much lower running current than a similarly-sized absorption fridge operating on 12V. But here’s the chill factor: this setup requires at least two 80W panels for your fridge alone – and that’s without giving any thought to all of your other electrical needs.
Given most RVs have a gas system installed, an absorption fridge is quite practical because most fridges consume about 15-20g of gas per hour. That means that when used with a gas cooktop, for example, a 9kg gas cylinder is going to last up to two weeks. A couple of weeks or so of camping in your favourite outback spot before having to race into town for more gas is not bad going.
Then again, no matter what fridge you choose, don’t overlook the fact that eventually you’ll need to replenish your fuel resources, which could become an issue if you are camped somewhere isolated. That means the fridge helps determine where you go and the health of your budget.
If you prefer caravan parks, you are probably best suited to a three-way absorption fridge because they offer the convenience of hooking up to powered sites, converting to gas or battery on the few occasions when you are going bush, or keeping the groceries cold with battery power when on the road.
A QUESTION OF POWER
Whether you’re running a 12V or three-way fridge, always use a deep-cycle battery.
Here’s the thing about deep-cycle batteries: they are constructed using thicker plates and a denser active material. This will withstand repeated cycles, rather than providing high bursts of power for short periods of time.
So deep-cycle batteries deliver sustained power with low current draw over extended periods of time. However, if you want to prolong the life of these batteries, make sure you have the right gear charging them, especially if using three-way fridges.
For example, to fully charge a 12V 55Ah battery over about 15 hours, the options include an 80W solar panel; a 5-10A 240V charger; and a 40-60A 12V generator.
Move up to an 85Ah 12V battery and you’ll need 80-100W solar, up to a 40A 240V charger and perhaps an 80-100A 12V generator (though a 40-60A generator may suffice).
If looking for lots of battery power, say 200-400Ah, you can forget solar and probably a 240V charger, too. The recommendation from manufacturers like Century is to stick with an 80-100A 12V charger for batteries of this size.
The bottom line is, if you are upgrading or replacing your electrical appliances, fridge, lighting, television, entertainment system or air-compressor, make sure either you or a professional properly assesses your power needs. Also, check with the various manufacturers for advice so you know your power needs are properly met. Otherwise, it can become quite expensive having to replace batteries too often.
When it comes to charging from the tow vehicle, something like either an Anderson or 12-pin flat plug should be used.
For DIYers, sparkies tell me you should always connect the fridge to the car using wire of the correct diameter. Lighter wire can result in lost voltage. For technically-minded folk, it’s all about Ohm’s Law – thicker wire means less resistance and less voltage drop. The advice is 8-10mm. Also, make sure the fridge is correctly ventilated to avoid overheating.
AUTO vs MANUAL
When it comes to three-way fridges, one choice is Automatic Energy Selection (AES) models. There are no moving parts in them because they’re totally electronic. AES fridges determine which power source is available and automatically switch.
For those dubious about anything automatic, you can always choose a fridge that allows manual energy selection. The trick here is to look at the position of the controls. I have come across one model with the controls down at floor level. After a long day on the road, the thought of getting onto the floor to change the controls left me cold. Why a designer thought placing the controls so low was a good idea baffled me.
Manual power selection isn’t so bad. Once you have selected the energy source, it will do everything automatically. If you select gas, for example, it will automatically light it for you.
On the subject of gas, impurities sometimes block the gas jets of three-way and gas fridges. In that case, the problem requires a call to a gas fitter.
Many old timers recommend turning fridges upside down to get them going if they play up – which was true for older fridges. But these days, all that does is upset the chemical and liquid balance in the back of the boiler and risk causing even more problems.
So when is it right to upgrade? The expert advice is that if your repairs are going to cost more than half the price of a new fridge, buy a new one.
When buying new, size does matter, but bigger is not always better. A full fridge is far more efficient than a half-empty one because air is hard to cool. Consequently, have a good think about the size of fridge you can afford, and what you need, before making your purchase.
Here are a few essentials to keep in mind for clever refrigeration:
>> Think about where you like to stay – free camping or caravan parks, the outback or in town – as this will help determine your power needs
>> Do not buy a fridge any bigger than your needs – remember you can use a portable fridge to supplement on the occasions your fridge is too small
Ensure the unit is properly installed, and the rear of the fridge is insulated from the inside of the RV
Make sure the fridge is correctly vented to the outside
Always keep your cool
WORDS AND PICS David Gilchrist
Source: Caravan World Dec 2011