Thetford Toilet Problem

RoaminRog

RoaminRog

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I have a Thetford C200 toilet in my Autotrail Miami 740S
Just recently the flush button stopped working.
I assumed it would be the Electric Valve inside the toilet bowl, and dismantled the assembly in order to access it.
Pulled the wires off, and the water pipe and thought I would check the voltage.
Using a multimeter on the wires, I was surprised to get a reading of 4.6v
Checked at the switch, and again 4.6v
Checked at the wire entering the fuse housing, and again 4.6v

The Electric Valve clearly has 12v written on the label, so I checked it using a leisure battery. I could clearly hear the valve clicking, which I am assuming means its working.

Can anyone throw a light on where to look next please.
 
Take the wire off after the switch and see if the voltage comes up to 12v, this will determine load is pulling the voltage down, if it stays at 4.5v then it is a bad connection. Is it the one pump that feeds the whole water system or is the toilet on it's own pump.
 
Herman said:
Take the wire off after the switch and see if the voltage comes up to 12v, this will determine load is pulling the voltage down, if it stays at 4.5v then it is a bad connection. Is it the one pump that feeds the whole water system or is the toilet on it's own pump.
Click to expand...

There is just one pump for the whole system. The water pressure is fine, its just that I dont think that 4.6v is enough to operate the electric valve. The low voltage is evident right the way back to the fuse.
 
It must be a poor connection in the supply circuit somewhere.

I would try reseating the fuse for that circuit in the Sargent distribution box as a starting point.
 
My push button switch developed a fault on my last van. It would work OK but would not stop when I released it and had to use the control panel to turn it off. They are a bit cheap and nasty, so I would try a new switch.
 
maingate said:
My push button switch developed a fault on my last van. It would work OK but would not stop when I released it and had to use the control panel to turn it off. They are a bit cheap and nasty, so I would try a new switch.
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Rog has tested the voltage before the switch so that rules that out as the fault.
 
According to another website, the minimum operating voltage is 10.5v (maximum 15.5) so I think I am looking for a bad connection or corrosion somewhere in the supply wiring.
It may be easier just to run a new wire from a reliable 12v source.
 
Nothing much is going to happen over the weekend but in an attempt to trace the wires back I have removed the whole toilet. The wires go through the floor, underneath the bowl and then go towards the front of the van. Have checked all fuses, which seem to be fine, so looking for corrosion, wear, broken wire or whatever.
Busy week coming up, so may not be able to devote any more time to it until Thurs or Fri. Will report back. Thanks for all replies so far. R
 
Meanwhile for flushing before it is sorted, if you have combined shower and toilet, use the shower head - we find it more effective for flushing anyway.
 
nicholsong said:
Meanwhile for flushing before it is sorted, if you have combined shower and toilet, use the shower head - we find it more effective for flushing anyway.
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Cant really do it like that at the moment because the water pump is turned off so the electric valve could be removed for bench testing.
If I turn the pump back on it will just pour out of the pipe where the valve should be. Happy Days!
 
RoaminRog said:
Nothing much is going to happen over the weekend but in an attempt to trace the wires back I have removed the whole toilet. The wires go through the floor, underneath the bowl and then go towards the front of the van. Have checked all fuses, which seem to be fine, so looking for corrosion, wear, broken wire or whatever.
Busy week coming up, so may not be able to devote any more time to it until Thurs or Fri. Will report back. Thanks for all replies so far. R
Click to expand...

Is there any give in the wiring, could you get someone to gently pull and push while you look elsewhere to see movement? Its how I try first then once located I will tape new wire and pull through, unless you have cable chasers to push through the holes?
 
Nabsim said:
Is there any give in the wiring, could you get someone to gently pull and push while you look elsewhere to see movement? Its how I try first then once located I will tape new wire and pull through, unless you have cable chasers to push through the holes?
Click to expand...

Had a neighbour over who had a crawl about underneath, and the wires go through the floor, underneath the bowl, run forwards and then appear to re enter behind the ‘fridge, but then they diappear into the ceiling possibly?
Going to test, with an independent earth wire, to see if that will provide a 12v supply.
 
Neighbour came over again this afternoon and found that the positive wire was badly corroded. He ran a new wire through and now all working again!
The electric valve, inside the toilet bowl, was fine and working well.
The next project is to fit a bidet (on order from Italy) into the bowl before putting it all back together.
Thanks for all your help and interest,
Regards Rog.
 
RoaminRog said:
Neighbour came over again this afternoon and found that the positive wire was badly corroded. He ran a new wire through and now all working again!
The electric valve, inside the toilet bowl, was fine and working well.
The next project is to fit a bidet (on order from Italy) into the bowl before putting it all back together.
Thanks for all your help and interest,
Regards Rog.
Click to expand...

We were only showing interest for fear that you and Chrissy would be knocking on doors to relieve yourselves at meets 😂😂😂😂
 
The cassette full light/switch is my next little job to do. Blind and Garage locking bar, retainer have been sorted this week.

I will do the rounds with the meter first but have been told it can sometimes be caused by internal obstruction of the float magnet, so that might be a little more hard and umplesant to access.
 
Ed on Toast said:
The cassette full light/switch is my next little job to do. Blind and Garage locking bar, retainer have been sorted this week.

I will do the rounds with the meter first but have been told it can sometimes be caused by internal obstruction of the float magnet, so that might be a little more hard and umplesant to access.
Click to expand...

Im sure at some point, I came across something on Youtube about magnets becoming displaced and what to do about it. I can imagine the ‘attraction’ of doing that job. Surely you only need to look through the open flap to see how full it is getting.
Keep the videos coming Toasty....... all good stuff!
 
Ed on Toast said:
The cassette full light/switch is my next little job to do. Blind and Garage locking bar, retainer have been sorted this week.

I will do the rounds with the meter first but have been told it can sometimes be caused by internal obstruction of the float magnet, so that might be a little more hard and umplesant to access.
Click to expand...
My light hasn't worked for over 10yrs, I haven't bothered repairing it because I found it came on too early and I still had to look inside so couldn't see the point
 
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