Before you hit the road on your caravan holidays, every caravanner knows you must check the pressures of the tyres on your tow car and caravan. And as this could be a rather long and slow job if you’re using a foot pump, a portable, powered compressor is a very useful item to have in your touring kit. So here at Practical Caravan, we brought a group of such tyre compressors together and tested them back-to-back, meaning you have the knowledge to buy the best without having to do the legwork.

Having tyres at the correct pressures is a matter of safety. But as under-inflated tyres can also hurt your fuel economy, performing these checks could also save you money.

Every tyre compressor reviewed in our group product test was assessed in the same way. Speed of inflation was an important part of this testing process, so every item had to inflate a 205/55 x 16 tyre from flat to 30PSI, against the clock. And by using the compressors, we were able to see how user-friendly – or otherwise – they were.

Good features included long air hoses and power leads, which make positioning the compressor much easier – cordless devices were even better. We also noticed that some higher power models attach directly to a battery’s terminals, which is an advantage when you are either inflating or deflating a tourer’s tyres because of the close proximity of the leisure battery.

We also liked tyre compressors with easy-to-read gauges, and digital gauges seemed to fare particularly well. Another desirable feature is an auto-stop function, which will automatically turn the compressor off once you’ve reached the pressure you want, meaning you can leave it working while you get on with something else. A product with lights will be easier to use in the dark, plus an integral high-volume low-pressure pump will mean that you won’t need to take a separate pump with you on tour.

In testing, our team also realised that they preferred screw-on style couplings between the air hose and the tyre valve, as they are easier to use than other types and more foolproof, too.

Here we put the Ring RAC900 through its paces. With a £74.99 price tag, it was the most expensive portable tyre compressor we tested by quite some margin. And, indeed, this is quite a different beast to most other compressors we reviewed. In fact, its manufacturer Ring classes it as a professional model, which certainly explains the significantly boosted performance — this took just 1 min 40 secs in the inflation test.

But while the speed is great, niceties such as a digital gauge, an auto-stop function and lights, are conspicuous by their absence. On the plus side, you get a 7m-long coiled hose between the compressor and the screw-on tyre-valve coupling, and the compressor itself can be up to 2.4 metres from the battery, thanks to long power leads that clamp directly to the battery’s terminals.

So, if you’re shopping for a portable tyre compressor, what others are out there? We also reviewed the T-Maxx Portable Compressor which received a three-star rating, the one-star Draper 65958, the Halfords Multi-Purpose Inflator which got five stars and the four-star Michelin Hi-Power Rapid Tyre Inflator.