TomMurray,

What does the Qi device user-manual say about the red status LED? In my own use-case, the Qi charger has different LED colours, Blue is a slow charge rate of 5w and Red is 7.5w (fast charge).

I find the Roam charges at a rate of 5w, but as with many Qi chargers it’s often a lesser charge rate than the one advertised by the Qi manufacturer. 

It takes over 7 hours for my (cheap, but certified) Qi charger to fully charge a Roam, compared to 2 hours to 2.5 hours using a 5v/3A USB charger.

My fault, I was ambiguous.  The charger has no lights at any time.

The Roam has the Red light.  Or should I say Amber then?  Looked Red enough to me…

I left the Roam on the charger for a day or two and it eventually just lost all power and died.  I plugged into mains and it charged back up then showed the red/amber light when placed on the charger.

Perhaps try powering of the Roam (off the charger, long press on rear power button till device shuts down). 
Also power off the Qi charger for 30+ seconds and then try the charging process again. See if that fixes it for you.

Tried the old off and on again. No difference.

Tried again this morning and it did work. 

I guess it could be a one-off but I'll be frustrated if I need to continually periodically reset.

Thanks for help Ken, even if it was just to remind me to switch on and off first! :-) 

Curious as to what is feeding that Qi charger. It seems to imply different outputs based on what it is being fed, although the numbers look backward, I.e. the more voltage it gets, the more amps it should be putting out, if I understand my electrical theory properly. 

From what I’ve seen on other threads, if it’s putting out that 1.5 amp charge, it will be close to impossible to get enough energy transferred to the Roam. 

From what I’ve seen, the amps due tend to drop with the higher voltage on low voltage devices.  You do tend get more total watts, but it’s diminishing returns.  5V * 3A = 15W...9V*2A= 18W...12V+1.5A = 18W.   These are surely not exact numbers as well.  And of course, that’s the input.  I know very little about wireless charging, but it does seem to depend on capabilities of both devices and how good of a connection is made.  These charging pads seem to charge less if the device isn’t placed in the middle of the pad….the impression I get anyway.

Output is 15W, not sure what volts and amps are for that.  Perhaps it depends on the input...don’t know.

It is the plug from my Samsung S10e charger.  The phone fast wireless charges on the dock.
 

The dock is this one 

https://www.amazon.co.uk/gp/product/B08356QG7W/ref=ppx_yo_dt_b_asin_title_o02_s00?ie=UTF8&psc=1

You are right, I am not sure those numbers add up…!

I can’t say for sure, but I think that charger is 5V/2A...or 10W max input.  I suspect you’re getting a bit less on the output side of the wireless pad.

Some wireless chargers, very similar to the one you’ve linked, have additional logic built in to detect what model device is placed on it. It’s very unlikely that your charging pad will know what Roam is and thus only provide the standard charging rate that the pad puts out (likely 5W). I’d contact the manufacturer to confirm for sure, but the product image that displays the different charging rates for different brands/models of phone pretty much gives it away.

I guess that makes sense James.  So what are we supposed to look for in order to find a suitable charger?  Or is it just pot luck?

I’m afraid that Qi charger output can vary wildly from model to model, as well as the device placed on them. I would look for a charger that can output 10W as standard, that doesn’t specify the type of device that would receive it (i.e. Apple - 10W, Samsung 15W etc). The way different manufacturers list their products isn’t very standardized, especially on Amazon, so before biting the bullet and ordering a different one, I’d reach out to the seller to find out the exact specifications, and how the charger would perform with devices other than mobile phones. Good luck!

Its the wrong Pad for the job.