Here's what you should consider before you buy a freezer.

Chest or vertical?

Size and shape
A chest freezer is best for maximum storage capacity as they are available in sizes up to 700 litres. But a 700 litre chest freezer occupies a lot of floor space.

We don't know of any really large vertical freezers - 389 litres seems as big as you can get. If you want a pigeon pair - identical, but separate fridge and freezer - in your kitchen, vertical models are your only choice.

Convenience
Vertical freezers are usually more convenient to use because you don't have to dig down through the layers of frozen food. Smaller chest freezers can be very awkward to use once packets get buried at the bottom.

Chest freezers are not frost-free so you have to defrost from time to time. If you don't open the lid too much or leave it up for too long, ice build up is slow, and defrosting once a year is usually enough. Look for a model with a drain bung at the front, so you can easily drain off the melt-water. Drain bungs with spouts help minimise spills. The drain should be high enough to fit a suitable container underneath. This makes defrosting easier.

Efficiency
Cold air falls (just as hot air rises), so as soon as you open the door of a vertical freezers all that lovely freezing air flows out. When the lid of a chest freezer is opened, cold air does not flow out, and not a lot of warm air will usually flow in. This helps make chest freezers more energy efficient than vertical freezers once door and lid opening is taken into account.

Frost-free freezer technology also uses more energy, which gives chest freezers a further advantage.

Size for size, a cyclic type chest freezer can use 25 percent less energy than a frost-free vertical model. But, the star rating system is confusing as it is different for each type. So, a 2.5 star chest freezer can use a lot less energy than a 3 star vertical freezer of the same size. It pays to compare the energy use figures on the label or check the Australian Greenhouse Office website which has a 10 year running cost calculator.

Features

Shelves, drawers, baskets and partitions
Vertical freezers are available with shelves or drawers. Shelves allow you to open the door and immediately see what's there. But check how movable they are, and whether they have lips to stop food falling out at the front, sides and back when you do move them.

Sliding drawers may take up more potential storage space than shelves, but they make it easier to access food: check they slide smoothly. Some have opaque fronts, so you'd probably need to label what's in them to make finding things easier. Drawers with a solid front also make the storage area more enclosed, so less cold air escapes when you open the door.

Baskets or partitions in a chest freezer help you organise the freezer for later retrieval of long-lost leftovers.

Controls
Check where they're located and if they're easy to understand and adjust. Some need a coin or small screwdriver to change the setting.

Liners
Some freezers come with soft, thin aluminium liners. Look for heavy-duty liners that won’t dent easily.

Interior light
A light under the lid of a chest freezer can make finding items easier.

Buying second hand

New freezers are more energy efficient - so if you're buying second hand, newer is better.

• Only buy if the freezer looks tidy and well cared for.
• Check the lid or door seal is intact and the door or lid shuts properly.
• Under the Electricity Act, all electrical appliances for sale must be safe – whether they're new or second-hand, bought privately or from a dealer.
• If you buy from a second-hand dealer and then discover the freezer’s faulty, you're covered by the Consumer Guarantees Act. If you buy privately, you're not.