The Ultimate Guide to Fridge Freezers
The ultimate guide to European fridge freezers 2010
Looking for a fridge freezer? Don't buy one until you've read this guide. If you don't have time to read the whole thing (and that's cool, I understand, I'm a busy person too) I've included a super-quick guide on what to look for at the end of the page.
If you're reading the whole thing then we're going to start with the basics of refrigeration before moving on to cut through the marketing hype and look at the features you need and those you don't. At the end we'll be rounding off with a look at some of the models that stand out from the rest.
About the author
Tall, thin and devilishly charming - all features which I admire in other people. Unfortunately to learn this much about a subject as boring as this you have to spend years working in the white good industry which can both pile on the pounds and erode any personality you may once have had.
I sell fridge freezers for a living so I understand that they can be perilously boring. But it is better to make the right decision now rather than regretting it later because the average lifespan of these appliances is between eight and ten years.
Obviously I would encourage you to visit my appliances website but this guide has been written to be impartial and informative - not as an exercise in sales.
So without further ado I present the Ultimate Guide to Fridge Freezers 2010.
Basics of refrigeration
The microorganisms which are responsible for the decay of food reproduce more slowly at lower temperatures. That's why food that's stored in a cool place takes longer to go off than food kept in the warm. At temperatures under 0 degrees centigrade most bacteria actually deform as the water inside expands into ice so they stop reproducing altogether which is why you can keep food in a freezer almost indefinitely without it starting to rot or go off.
Refrigeration is one of those things that's easy to use but hard to understand. By far the most common method of refrigeration is to use a compressor - there are other options available but you won't find them in a common household fridge freezer.
The substance inside a compressor (the refrigerant) is a gas. Under normal conditions the molecules in a gas have plenty of space to move around but when you put them under pressure they get closer together which means that some of the energy that went into their movement is released as heat. When the pressure decreases (increasing the amount of movement in the particles) so does the temperature and the greater the drop in pressure the more noticeable the effect.
The compressor in a fridge freezer is split into two parts; a high pressure, high temperature side on the outside and a low pressure, low temperature side on the inside which is what keeps it cool.
What size do you need?
The amount of storage space inside a refrigerator is expressed as the volume of its cavity - this is normally measured in litres or cubic feet. The larger the volume of the fridge freezer, the more food it can hold but there needs to be some room between the items in the fridge in order for cold air to circulate.
As a rule of thumb 50 -80 litres (two to three cubic feet) of capacity will hold enough chilled and frozen food to last an adult a week. This is a very rough guide based on a European average so you should always consider your own habits and how space has been divided inside the appliance. If you are an alien who only eats metre tall spears of frozen yoghurt then you're going to need a freezer that's at least a metre tall with no pesky obstructions like drawers in the middle. If one shelf of your fridge is always full of sauces and condiments then you're going to need room to store them all.
But don't worry that you're going to suffer for not having a massive capacity. Most manufacturers include ways to make the most of the space you have available to you.
Storage features explained - essentialsClick thumbnail to view full-size
Storage features explained - nice to haveClick thumbnail to view full-size
Storage features explained - dubious valueClick thumbnail to view full-size
Hygiene and freshness features explained
So long as a fridge chills to below 6 degrees and a freezer to less than 18 they are doing their job. But some manufacturers would have you believe that their appliances have extra hygiene or freshness features that make a real difference. In this section we'll look at what these are and how they work.
Antibacterial lining - an antibacterial agent like silver is included in the coating of the cavity. The theory is that by keeping the amount of resident bacteria down you will prolong the life of stored food. There is evidence to suggest that this can work but much of the bacteria that ends up on food comes from human contact - not from the wall of the fridge.
Removable door seals - the theory is that these make it easier to clean your door seals. In practice it is probably just as easy to wipe whole seal down in situ as it is to take it off, wash it in the sink and then put it back on again. Having said that, if your seal fails having a removable one makes it much easier to replace.
Vacuum sealed compartments - a very few of the most expensive fridge units come with vacuum packing sections. This does increase the shelf life of your food but at the same time if you buy only what you intend to eat within a reasonable space of time you should never need it. It is useful if you grow your own food and can't bear throwing it away.
Humidity controlled salad crisper - not as impressive as it sounds. A humidity controlled salad crisper is any salad box with holes in it. By covering the holes or leaving them open you can adjust the humidity within the box. Some foods stay fresher with high humidity (holes closed) while others with low humidity (holes open).
Turbo or fast freezing mode - reduces the temperature in the freezer beyond its normal minimum so that when new food is loaded it freezes quicker. For most models you have to remember to turn this function on before you go shopping in order for it to be ready in time for you when you get back but despite this flaw it is worth getting. By freezing food quicker you reduce the size of the ice crystals that form inside it which means there will be less of a change in taste when you defrost and eat it.
Turbo chilling - increases the circulation of cold air through the cavity of the fridge in order to help chill food quickly. Some people notice a difference, others don't. It depends largely on how much food you load at once and whether you are bothered by how quickly it gets cold. In theory it should make a difference but if you are using your machine properly then it is not an important function to have.
Safety glass shelves - the chunky glass shelves that many fridges come with are actually safety glass. When it breaks it shatters rather than splinters which means it's a nightmare to clean up but it is a lot safer than regular glass. The strange texture that it comes with is designed to be non-slip and to stop spills from spreading. It is not unusual for a safety glass shelf to hold up to a pint of liquid before it starts to overflow. While this is a brilliant feature it is not uncommon so it should be something you demand rather than dream about.
Air purifier - filters air as it circulates. Arguably a waste of time unless if you're going for a "belt, braces and then another belt" approach.
All white goods sold within the European Union come with an EU Energy Label that contains important information about that product. For fridge freezers the label gives;
- An overall grading for the energy efficiency of that unit with A++ being the highest possible grade (due to rise to A+++ in 2011) and G being the lowest.
- The average amount of energy the machine uses in a year as measured in kilowatt hours.
- The available storage space for frozen and fresh food as measured in litres.
- The noise level measured in decibels.
- The star rating of the freezer.
What is climate class?
Refrigeration products only work properly within certain temperature thresholds. Climate class lets you know what those thresholds are for that machine. The household climate classes are as follows;
SN - Stands for sub-normal which means that a machine will operate in ambient temperatures between 10 and 32 degrees celsius.
N - N is for normal. Normal temperatures are deemed to be between 16 and 32 degrees celsius.
ST - is the sub-tropical temperature range of 18 to 38 degrees celsius.
T - tropical is the highest temperature range and stretches from 18 to 43 degrees celsius.
Why is there a minimum temperature? Surely the colder it is the less it has to work.
The refrigeration process in a fridge or freezer only turns on when a sensor thinks it might be getting too warm however the thermocouple that detects this isn't placed inside the cooling cavity. Instead it measures the temperature at a point where cold leaks out of the unit (like where the compressor pipes enter and exit the back wall) because under normal conditions this is much more reliable than measuring air temperature.
The problem occurs when the ambient temperature drops below the point at which the thermocouple is set to detect - leading the mechanism to believe that the temperature inside the fridge is lower than it actually is. It's a little bit like judging how hot an oven is by touching the glass door; you can tell it's on because the glass gets warm but if you leave it under direct sunlight on a hot day the door gets hot even if the inside of the oven is cool.
You can find out how loud a unit is by looking at the bottom of its EU Energy Label under the "noise" heading. This gives you a number in decibels that measures how loud it is under normal operating conditions.
It's worth bearing in mind that most people won't notice a rise of 1 decibel and a difference of three decibels is barely noticeable. Once you get a change of five decibels most people will say there is a noticeable difference and at an extra ten decibels a sound doubles in volume.
If you don't know how loud a given number of decibels is the list below should give you some idea.
- 30 db - a quiet library
- 40 db - roughly the volume of a well made fridge freezer
- 50 - 60 db - regular conversation
- 70 db - a fortissimo singer standing a metre away
- 80 - 90 db - a violin
- 100 db - motorcycle engine
- 120 db - point at which exposure causes pain
- 140 db - jet engine from 30 metres away
Frost-free vs auto defrost
These are two terms which constantly get confused with each other - even by people who should know better. Frost free is a function you find on freezers while auto defrost is for fridges. They both prevent a build up of frost by catching moisture from the air and releasing it back into the atmosphere of the room.
Frost-free - a frost-free freezer uses a fan to pull air out of the cavity and pass it through an evaporator where water from the air turns into droplets that freeze. The evaporator is periodically heated to allow the ice build-up to melt and trickle down a runnel onto a plate outside the unit. Water that sits on the plate evaporates into the air naturally.
Auto-defrost - the back of an auto-defrost fridge is chilled to be slightly colder than the rest of the unit so that water from the air will condense onto it and freeze - just like the evaporator in a frost-free freezer. Every so often the fridge will make the temperature of the back wall rise to be the same as the rest of the fridge which causes the ice to melt and run into a drainage hole which leads to a plate outside the unit. From here the water evaporates back into the environment.
There are two kinds of fit type; freestanding and built-in/integrated. Functionally there is very little difference between the two but built-in models are designed to have a panel attached to their front in order to blend into the design of the kitchen. For this reason built-in fridge freezers (and other appliances) are popular in designer kitchens but you will normally end up paying a little extra for one.
Freestanding units tend to be cheaper and because they are visible they can be designed to look good. However, the really attractive models, cost about as much as built-in units so don't be fooled into believing that they are a cheaper way of making your kitchen look good.
There are three types of fridge freezer; American (also known as side-by-side), combi and top mount. In theory the only difference is the layout and positioning of the cooling cavities but in practice this isn't the case.
American fridge freezers are by far the largest of the three types with an average width of about 90cm (around 150% the standard size). They're more expensive, more likely to come with a water dispenser and generally come equipped with more features.
Combi fridge freezers are the UK's most common kind. They have the fridge cavity sitting on top of a slightly smaller freezer cavity (usually a 60:40 or 70:30 split) and while they can come with some of the features more commonly found in American style models they generally don't.
Top mount fridge freezers are normally found at the cheaper end of the price spectrum and are less likely to have any fancy features. The freezer is mounted on top and is always significantly smaller than the fridge.
Freezer star ratings
All iceboxes and freezers are assigned a star rating from 1 - 4 depending on the temperatures they maintain.
* - An icebox with a working temperature of -6 degrees celsius. Recommended maximum storage time of 1 week.
** - Another icebox but this time with an operating temperature of -12 degrees celsius. Sometimes soft ice creams (the type that come out of a tap) are stored at this temperature in commercial kitchens. Recommended maximum storage time of 1 month.
*** - The coldest type of icebox, ideal for storing all kinds of pre-frozen food at -18 degrees. Recommended maximum storage time of 3 months.
**** - The only star rating you will find on a proper freezer. Suitable for long term storage (up to 12 months) and able to freeze fresh food.
Please note - Although three and four star freezers both maintain the same temperature only four star models are good enough for long term storage and freezing food because they respond better to changes in temperature - three star ice boxes go through the same cooling process irrespective of the internal temperature.
Long term frozen storage and freezer burn
Even though a four star freezer can store food for up to 12 months (and in some cases beyond) this doesn't mean that you necessarily should.
When fresh food is frozen its water content turns into ice crystals. Every time you open the door to your freezer warm air gets in and can cause some of those ice crystals to defrost. Once the door is shut the crystals refreeze but not necessarily in the same shape that they were originally in. This constant movement within the mass of the food damages the membranes of cells and causes it to lose flavour.
Another disadvantage to long term storage is an increased risk of freezer burn. Freezer burn occurs when water evaporates from the exposed surfaces of meats leaving them dried out and looking burnt. Vacuum sealing food helps prevent the process of freezer burn but even then it can occur.
Some high end combi fridge freezers and many American units come with a water dispenser built into the door. This is a tap that dispenses chilled water and sometimes ice cubes and crushed ice. Most apertures (the bit you put the glass in) are big enough to take a pint sized vessel however do not expect them to be able to take an upright 330ml bottle - only specially designed models have this feature.
When choosing a fridge freezer with a water dispenser the big choice is between plumbed-in and reservoir-fed.
Plumbed-in - pull water directly from a mains supply before cooling it. This requires the unit being connected to your mains water supply -literally plumbed in. The network of pipes and cooling apparatus takes up a significant portion of fridge or freezer space so units with this style of water dispenser often suffer from severely reduced storage space.
Reservoir-fed - have a large bottle or reservoir that needs to be manually filled. This style of dispenser is useful if you do not want to have your fridge freezer plumbed into the mains water however it does have a distinct disadvantage in that it needs to be refilled by hand.
Models of noteClick thumbnail to view full-size
A few interesting links if you want to do more detailed (but less commerically relevant) research.
- Fridge freezers
Gratuitous plug for my own site.
- Normalisation fo the freezer
An interesting paper about how the British public have grown to accept the freezer.
- Fridge mountains
A look at the disposal of fridges and how regulation from the early 2000s has unexpected side affects.
If you're looking for a career in refrigeration then check out this course from Grimsby Uni.
Super Quick Guide
If you're looking for a fridge freezer you should really read the full guide as the super quick guide is only a set of guidelines - they're good guidelines but I wouldn't want you assuming that they can be applied to every situation. As with everything you need to use a little common sense and discretion to find the right fridge freezer for you.
There are two sections - demand and expect. Do not buy a fridge freezer unless it meets all the criteria under the demand section and consider features in the expect section as added extras which are nice to have but not critical. For the sake of brevity all other features have been omitted from the super quick guide.
Demand - fridge door balcony, adjustable height shelving, freezer drawers, 4* freezer, turbo freezing mode, safety glass shelves, A class energy rating, noise level less than 50 decibels and 50 litres of capacity per adult in the house.
Expect - winerack, freezer door balcony, extra large freezer drawer, water dispenser, antibacterial lining, air purifier, 43dB noise level or less, A++ energy rating, 80 litres of capacity per adult in the household.