Air fryer builds have trends, like everything else, and right now air fryer ovens are having a moment.

While air fryers – which are really just mini convection ovens – started off as fairly compact appliances with a single pull-out drawer, larger models are becoming more common. Air fryer ovens, as they’re called, have a bigger capacity and, in fact, look just like the inbuilt oven in your kitchen, with a number of rack heights, an internal light, and pull-down door complete with a viewing window.

These countertop ovens will need a correspondingly large amount of space. That’s certainly true of the massive 24-litre HySapientia air fryer oven, although it’s a versatile cooker, even boasting a rotisserie function.

HySapientia is an air-fryer-specific brand. You can buy its appliances in the US and the UK.

Design & Build

• 10 pre-sets
• Stainless steel build
• Viewing window and interior light

One of the best things about the HySapientia air fryer oven is its build. It’s made almost entirely of stainless steel and other food-grade metals, which makes a nice change from the plastic air fryers we tend to see. Still, it feels a bit rattly and certainly not as solidly built as a microwave, for example.

As you’d expect from a 24-litre capacity appliance, it’s huge, with dimensions of 16.8 x 18 x 16.5in/ 41.4 x 37.5 x 37.5cm. It’ll need a 4-inch/ 10cm clearance around it, so you can’t keep it flush against the tile. But it looks good on the counter, as its bright steel means it’s not a light-sucking black monolith like so many competitors.

There’s a large viewing window in the door and an internal halogen light you can switch on, so you can monitor whatever is cooking inside.

It’s controlled via a dial and a series of six buttons. The display shows 10 presets, plus time and temperature.

Emma Rowley / Foundry

The presets include toast, bake, fish, dehydrate, grill, air fry, defrost, steak, pizza and rotisserie. But you’ll have to revert to the manual to decipher these as dehydrate is represented by a carrot and grilling by a chicken leg. You can also choose a high or low fan setting.

You choose a preset by using the dial and although it’s straightforward to understand, it’s annoying to use. For a start, the appliance beeps at every setting, so turning the dial is accompanied by a loud ding! ding! ding! ding! ding! as it hits each preset, time or temperature option. I hoped to find a mute option in the manual but no such luck.

Second, with so many preset options, a dial is not the best option, as you’ll spend a lot of time turning it back and forth (to the tune of maddening beeping). A touchscreen would be much faster and more accurate.

Once you’ve chosen your preset, you can then adjust the time and temperature – again, by using the dial. But there’s no option to choose a time and temperature independent of setting. That means that for everything except dehydrate, you can only choose a cooking time of up to an hour. Dehydrate gives you 240 minutes, but the heat is capped at 70^oC/ 160^oF. Overall, the appliance has a top temperature of 230^oC/ 450^oF.

To take advantage of the huge capacity, I decided to roast lamb. The time suggested on the package’s cooking instructions was two hours. I knew the air fryer oven would need significantly less time but it still meant returning to reset the appliance for a second cooking period. It’s not ideal for an air fryer oven of this size.

Equally, the shortest cooking time is 5 minutes, so if you want to reheat something that won’t take a whole 5 minutes, you’ll need to hover around the appliance until it looks ready.

One last word on the display. When you turn the air fryer oven off, the display reads OFF – all the time. So, you’ll come into the kitchen for a glass of water in the middle of the night and the air fryer will still be displaying a glowing OFF to remind you that it’s OFF.    

Emma Rowley / Foundry

The air fryer oven comes with a variety of accessories including a mesh air fryer basket, roasting tray, crumb tray, oven rack, fetch rack, rotisserie spit and silicone oven mitt. It has everything you’ll need to make the most of its various functions but you’ll then need to find somewhere to store all the bits. Keeping them on top of the appliance is not recommended and besides, your cooking will be accompanied by the sound of jangling metal trays.

Performance & Features

• 5-60 mins cooking time (except in dehydrate mode)
• Crispy results
• Cheap to cook entire family-sized meals

One of the reasons to buy this appliance is its versatility. You can do anything with it, from making toasties, to baking, to defrosting pizza, to making roast potatoes. If you find your current air fryer’s size a frustration when cooking, that won’t be the case with HySapientia’s 24-litre air fryer oven.

But the downside is that if you only want to heat up a couple of fish fingers for your kid’s supper, you’ll be heating up a lot of empty space and it feels like overkill.

It’s an 1800W appliance, which means that on the current UK price-capped tariff, it’ll cost you 26p or less to cook for half an hour. You can find out what it’ll cost on your tariff by using an online energy calculator.

But there’s a money-saving upside to its capacity. If you have a smaller, pull-out drawer air fryer, you’ll only be able to cook one dish at a time – for example, chips or chicken nuggets.

Emma Rowley / Foundry

In this appliance, you’ll have space for both, or more, which means you can cook an entire meal at once for much less than it’ll cost in your integral oven.

There’s a learning curve to using this air fryer oven. Happily, it does come with a recipe book, which offers recipes for every preset. However, they tend to focus more on complete recipes, rather than oven-cooking guides, meaning there are plenty of sentences like: “When the mutton is cooked to your taste, take it out.” There are also a few translation oddities sprinkled throughout the text.

The air fryer oven is easy to set up. Just remove the packaging and stickers and wash the accessories in warm, soapy water. Then you’re ready to go.

I tested the air fryer oven for a period of three weeks, using it in place of both an air fryer and oven. What most impressed me was the crispiness of the food cooked in it, probably because the large cooking space allows plenty of hot air to circulate. From crunchy, melty toasties to crispy roast potatoes, gnocchi, roasted butternut squash, frozen pizza and chips, almost everything I cooked in it came out well – and all done much faster than in an integral oven.

However, I didn’t find the presets particularly helpful and until I worked out times and temperatures, I spent far too much time peering through the cooking window, trying to decide when a dish was ready. It was particularly difficult to judge when a shoulder of lamb was done. If you want to cook a joint or other large cut of meat, we’d suggest investing in a meat thermometer to ensure it’s perfectly cooked.

Nonetheless, the lamb was a success, the meat juicy and the fat crisp.

Emma Rowley / Foundry

After cooking, I found the interior and accessories easy to clean, except for the window. It’s dual layer but water and oil can get trapped between the two panes of glass. You’ll need to unscrew in the inner glass panel to clean it thoroughly.

Price & Availability

The HySapientia 26QT/ 24-litre air fryer oven is available from Amazon US, with a MSRP of $199.99. However, at the time of writing, it’s available for $159.99, which is what we think you should pay for it.

It’s a similar story in the UK, where its full price on Amazon UK is $199.99, but the current offer is £159.99.

It compares favourably with the pricing of other, large capacity air fryers, such as the Tefal Easy Fry air fryer oven and the Ninja Foodi Max Dual Zone. For its build, enormous capacity and feature set, it’s very well priced.

Should you buy the HySapientia 26QT/ 24-litre air fryer oven?

Because of its size, this is something of a niche product. You’ll essentially have a second oven in your kitchen, which is not for everyone. But if your current air fryer is too small and you want more cooking space – particularly if you’ll use its rotisserie function – it’s great value, easy to use and will deliver impressively crispy results. All we’d caution is that the control panel could be faster and less of a beeping nightmare to use.

Not the right air fryer for you? See all of our top recommendations in our round-up of the best air fryers we’ve tested.