no, all nukes made since the early 80s use choke doors rather than
seals, and aren't sealed.

What is a choke door? Even wikipedia is silent on that subject.

If there's no seal, that would explain how the steam gets out, so I am
reassured, thank you very much.

The perimeter of the door is shaped so that it acts like a choke at
2.4GHz. The general public seems wedded to the idea that nuke doors
have seals, it was true in the 1970s but theyre long gone now. The
choke design is much safer.

NT

Funnily enough, it is a Sharp microwave obviously a common problem.
Is it easy/ cost effective to fix?

In terms of the bottles, we heat the water only in the microwave then
add the powder afterwards - much easier than messing around with jugs
of hot water etc.

At the time we were fixing them I think we paid 39GBP + tax for
the module for most models. If it wasn't a scam, it was certainly a big
money-spinner for Sharp. Each model has a different module.
Believe me, we were capable of repairing most stuff to component
level but we had no choice in this case as the problem seemed to
be a ribbon cable that was bonded to the glass LCD at one end
and similarly bonded the small pcb that carried the microprocessor.

I must have replaced hundreds of the damn things, I suppose it
was a money-spinner for us too.

I suppose you will have to conceder it as BER, or carry on
working it blind.

--
Graham.

%Profound_observation%