How do I open the door of a Smeg tumble dryer DHT71EUK-1

Many dryers have two heating elements, and provide low, medium and high heat by using element 1, or element 2, or both elements on together. I found this, so I think my idea is correct.

Heating element 1,200W + 1,000W

so, 1,000 watts, 1,200 watts, or 2,200 watts.

You have a single failed element. The other possibility is a thermistor or sensor failure, so don't just replace the element, test is for continuity with a test meter.

https://www.google.com/search?q=Smeg+DHT71euk-1+heating+element

and just to throw a spanner in the works, this review says is it a low heat dryer.

https://www.hughes.co.uk/blog/review-smeg-dht71euk1-7kg-condenser-tumble-dryer/

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The door actuator mounted on the door or the switch mounted on the dryer is missing or broken. The dryer is supposed to stop if the door is opened. Replace the door actuator or the switch.

Well we know the door switch is functioning properly so that usually just leave a timer issue.

you have 2 kind of problem:
1) Noises:
Rollers
worn rollers replace
Idler pulley
worn replace
Glides
worn plastic or nylon replace
Rear drum bearing
worn bearing replace
Blower wheel
clogged, clean it.


2)Not Tumble:
1) Clean the blower fan for clogged
2) Rotate easy the motor manual, otherwise motor defective replace
3)belt worn or defective.
4) door switch, test for open or defecive. see the video.

When start button is pushed there is a buzzing noise but dryer will not start.

there is a relay that latches on when you push the start button .. that relay is released by the "door open" switch .. i would suspect that the "door open" switch is bad .. thats usually a button that is pushed in when the door is closed ..

A tumble dryer that isn't heating up at all needs checking with a continuity test meter. The most common cause is a heating element failure, or t.o.c's going open circuit. It depends on which make and model of tumble dryer you have as to how easy it is to get to the relevant parts. Some tumble dryers have heating elements that are easily accessible by removing the back panel, and can be tested for continuity or checked for obvious breakage. Others though have their heating elements inside, which aren't accessible without stripping the dryer down. Tumble dryer heating elements are always protected by thermal fuses which are usually simple devices with 2 wires connected. They can be tested for continuity with a test meter
or
If power is getting to the tumble dryer and the socket is definitely OK, then the most common problem with tumble dryers not working is when the door micro switch fails, or the catch on the door that operates the switch either breaks or no longer activates the door switch. Check for broken door catches. There is usually a plastic peg on the door that pushes through a hole in the tumble dryer's casing where the door catch is. Closing the door should operate a simple micro switch. If the plastic peg is broken or bent it might not operate the switch properly

Possibly the belt assembly. if you open the door and try to turn the drum does it turn with a little resistance, noises? this model has rollers, pulley, and a four groove belt 92 1/4" , sometimes the pulley sticks after yrs of use, belts wear, drum misaligns. the humming should be the motor trying to work.

HI your right on the money , it is the belt. replace thanks.