This 3rd version of the Dyson heater is improved in ways, but when I got mine, I was not expecting it to be worse than the AM05 in ways.
It is improved enough to be considered a better heater than the AM05, but only because it has more options.
This AM09 model is slightly taller and heavier than the AM05.
This AM09 has a timer, the AM05 does not.
This AM09 has the jet flow design and broad airflow mode, the AM05 only had the one airflow mode, which to me seems like it was capable of moving air almost as far as the newer AM09.
The AM09 remote has a cold and hot shot buttons, one press of the blue button, and it goes directly to fan setting, one press of the red button, and it goes directly to the last set temperature which it was heating the room at. The AM05 had to perform a really inconvenient process on the remote of pressing and holding the temperature up or down buttons to go from fan to heating modes, when the digital readout got down to 32 degrees, then it was on the fan only setting.
This AM09 heater is quieter than the AM05 heater, but I have found that it achieves some of its improved quietness, from having a decreased airflow in the heater mode.
The airflow in the fan only mode on both models, seems to be equivalent.
I bought this Dyson AM09 to replace my AM05 as my living room heater, so it was a direct swap, and the AM05 is now a bathroom heater, yes my bathroom does have a ground fault power receptacle to prevent electrocution. Anyway, placed my new AAM09 in the same exact location as my AM05, this AM09 does not move quite as much air in heater mode, when compared to the AM05, but it is quieter, I just wish they would not have tried to achieve some of the improvement by decreasing the airflow in heating mode.
Both the AM05 and the AM09 do have a lesser airflow in any fan speed setting when the heater is on, compared to just the fan setting, this is on purpose, to avoid so much airflow that it might cause a customer to think it is not putting out air that is hot enough. Dyson engineered their heaters, so that the heater setting has less air flow in any speed, to make the air output feel sufficiently hot on even the highest fan speed.
Many customers must have complained that the Dyson AM05 was too loud, so they improved this AM09 and made it quieter mostly by improved air flow channels on the inside of the heater, but I can tell that some of the improved quietness when operating, is from it also having a decreased airflow in the heater mode.
That was not even necessary at all, they effectively decreased the effective heating capability of this AM09, in efforts of trying to avoid customers complaining about it being loud.
The fact that they made it quieter by way of improved airflow channels, was all that was needed.
Having slightly decreased the airflow in heating mode, makes this newer AM09 less able to heat objects further away from the heater.
Comparing the two heaters, the AM05 blows the heat further away from the heater, more effectively heating objects further away, but it is louder than the AM09.