Problems with Thetford C250 not flushing. Any help would be much appreciated.
Fuse at the back of the pull-out waste container is lit.
I have replaced the small motherboard on the post also at the back of the container which detects the waste capacity.
I have replaced the switch motherboard on the top of the toilet itself, and finally have replaced the pump accessed from the back of the container cavity. Still no flush.
Can anyone suggest what may be the problem now?
Is the pump running? If not that might have been what needed repair-replacement.
If yes then it could be a blocked pipe or too much lift problem
I ran the reservoir dry once (different model) and had to trim it right up to get the pump primed - then it was away again.
Usual cause of non flushing C250 / 260 is the impeller is jammed by black gunge. Black gunge is caused by using pink fluid in the flush tank and not draining.
Fix is to remove the impeller / clean the impeller / drain the tank a couple of times by flushing (drain tube is too small for gunge to get out).
The work is a lot simpler than it sounds (I've done it - no new parts needed ).
There are many youtube videos. e.g. &
May not be relevant, but have an issue with the fan on the same system, was told by an engineer that they have a habit of failing , apparently a system fault. He said forget the fan and as long as it flushes don't worry .Motherboard in the back of the pan was working .