I don't think that I've found a spare part! When I opened the toilet door to empty our cassette recently, I found a small spring (30mm long end to end) that has hooks at 90 degrees to one another.
There is no reference to it in the manual & a friend also had a look but could not offer any advice either. Can anyone assist?
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Warren
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If you don't get it done today, there's always tomorrow!
There are springs and there are springs. You say spring and most would imagine a coil, but the Thetford also show some simple straight wire springs in there, with sharp right angle bends.
Just google Thetford and the number to track it down.