Bought Hotpoint CTD00G Aquarius tumble dryer 15 months ago. Just stopped working. Drum appears to spin with no clothes in but not with wet clothes in. Feint smell of burning when left on. Just hums with no spin. Cleaned all bits, filter, water container, condenser, air in/outlets. No joy. Any ideas?

That sounds like an overheating problem. When the machine pauses, the blower fan stops running and that allows the heat to build up enough to trip the high level thermostat. You can test this by running a cool cycle.

Drive belts don't squeak because they are made of rubber. Things that do squeak are rear drum bearing, front bearings or drum slides, idler pulley wheels or the tension springs.

The machine needs a full strip down, cleaning, de-fluffing and lubrication. Also check the exhaust hose and the grill outside except it appears you have a condensing dryer. Make sure that unit is clean..

https://www.manua.ls/hotpoint/aqcf-852-b-i/manual?p=3

..

Since no dryer I am aware of uses any liquid, I suggest you may be putting wet clothes into the dryer.
This can happen if the washer does not spin the clothes nearly dry. Many dryers have small holes in the dryer drum to let excess water flow out, I would guess that may be the case with yours.
Are your clothes nearly dry when they come out of the washer?
If not, perhaps the washer has a loose belt or has a problem with the "dry" cycle.
God bless your efforts.

Either the belt is broken or possibly the motor starter has failed. Very often the belt. Be warned though, modern day tumble dryers use stretch belts that can be very difficult to fit.

that isn't a model number,open the door to the dryer,look around the opening where you put the clothes in and send the full model number,

Two things to check.
Remove rear cover.
Remove large black hose onto drum
Remove and clean filter inside hose.

Next--remove top cover and check the brushes in the motor, if they are less than 3 or 4 mm long, then replace them.
Please rate my solution.
Thanks.

Hotpoint tumble dryer not turning? How to replace a Hotpoint tumble dryer belt.
This video will show you how to replace a tumble dryer belt in your appliance
Please remember to subscribe to our YouTube channel for all appliance tutorials
a 4 THUMBS rating is appreciated for answering your FREE question.

no brushes in those motors you need new one or different dryer

either the motor is stuck or the belt is broken or has slipped off the tensioner.

Most likely it is some sort of blockage in the vent, although it could be a bad blower. Check the lint filter and vent openings for a blockage.