The unit silently oscillates up to 350°, and you can set it for 45° increments – handy to stop air blowing over your sleeping partner.

Both devices have a forward projection (fan style) and a diffuse projection (blows air back – not at you). It has a timer for up to 9 hours.

Warning: A fan cannot cool.

Whatever the ambient air temperature is, that is what it blows out. A fan can provide a minor cooling effect via evaporation if you sweat – that is all.

The biggest complaint on Dyson customer reviews is that it does not cool as per its name.

Power

It uses a 20V/2.5A, 50W power adaptor with a 2m cable. We found the cable a little short, and the adaptor is a largish rectangle that could pose a trip hazard when used with an extension cable. It would have been good if Dyson sold an extension cable.

Size

The round desktop version is 352mm at the air loop and 691mm high. The tower is 206mm at the air loop and 1054mm high.

LCD colour screen

The screen can display air quality index (analogous with the NSW website), PM2.5 and PM10 volumes, NO2, VOC, Indoor temperature and humidity (at the fan intake). Missing is a CO2 measurement that would be handy for closed rooms.

Dyson Pure Cool

Dyson App

The app is for all Dyson air treatment products. It allows customisation of machine settings, shows historical data, set continuous monitoring (can shorten the filter life to 6 months), advises filter replacement time and more.

It can also enable Amazon Alexa Voice skill. What this means is that any request starts with “Alexa, ask Dyson Purifier to …”. Given that Google Assistant is winning the home automation race in Australia three-to-one over Alexa we trust that OK Google will come too (no response from Dyson on this question). It also does not support IFTTT commands – for example, if AQI is over 50, then start the machine etc.

Dyson Pure Cool

The app failed to complete set-up when the unit was more than 10 metres from the router. At three metres from the router, it was fine but when back in the bedroom it failed again. App performance (even when using a Samsung Galaxy Note 9 with one of the strongest antenna setups) was patchy.

 It uses Wi-Fi N 2.4GHz and a Google Home Hub placed even further away works fine.

After the initial app and Alexa novelty wore off, we found the remote far more convenient.

GadgetGuy’s take: Dyson Pure Cool

Dyson makes a better mousetrap – at a cost.

Please don’t get me wrong – Dyson sees products and makes them better. The gear is well designed, well made, and fit for purpose.

However, I am becoming increasingly critical of the marketing direction of the company that bears the name of such an esteemed engineer as Sir James Dyson.

It’s marketing now relies on a lack of facts and its dependence on inexact science is troubling. For example, all air purifiers should have a CADR rating and clear specifications for filter capacity etc. Dyson instead uses a highly misleading Coandă effect. Please, Sir James – return to your roots and bury us in specs. Stop trying to be the Apple of the appliance world where everything is glossy and dumbed down!