Sounds right, although, unless the heater is more than just a resistance device, polarity of the connection to the "motor" would make no difference.
Naturally, as always, the power input MUST be the correct polarity.
Thank you for your kind help.
I calculate that there is a 1.7A draw. ie (8.5w/5v)
I had a look at the same wpm on AliExpress. This is the comment that now concerns me, because I do not understand why the continuous current appears to be limited to .5A
"This is a speed governor with a maximum current of 2A. If the continuous current is greater than 0.5A, the 775 motor and the stroller motor will not move. Don't buy it wrong. It is not recommended to supply power greater than 12V, such as 12V lead-acid batteries, which may cause damage to the governor."
As I am not intending to use this on a 775 motor / stroller motor, can I ignore the warning or do I need to look for another wpm with higher rating?