Tecma macerator pumpout toilet woes

[Idle Days]

14 minutes ago, Tracy D'arth said:

Just swap the 2 wires over, its a DC brush motor it will run in reverse.

Thank you, but I would prefer to install a switch for future use.  I have ordered a double pole changeover switch but am doubtful of it's current rating, hence my question. 

[Tracy D'arth]

No moving parts in a portaloo , its just a tank that the emptier's vac pump empties.

DC switches need to have a heavy current rating due to the break arc. A switch that will cope with 10 amps on AC will fail prematurely at 10 amps on DC.

So I would suggest one rated at 10 amps minimum DC .

[David Mack]

I agree its no problem for the particular portaloo operator. Presumably they put the notice there to avoid things being left on the floor as there is no bin. But it may create a mindset in the general public that it is OK to put that sort of thing down the toilet. And that is distinctly unhelpful for those with toilets that can't tolerate things which aren't bodily waste or cheap toilet paper.

Edited August 9, 2021 by David Mack

[Tony Brooks]

7 minutes ago, David Mack said:

I agree its no problem for the particular portaloo operator. Presumably they put the notice there to avoid things being left on the floor as there is no bin. But it may create a mindset in the general public that it is OK to put that sort of thing down the toilet. And that is distinctly unhelpful for those with toilets that can't tolerate things which aren't bodily waste or cheap toilet paper.

 

That is why my boat toliets always have a prominent notice saying don't put anything down this toilet apart for cheap  toilet paper and anything that has been eaten or  drunk.

[Iain_S]

3 hours ago, Idle Days said:

Resurrecting an old thread, but what type of reversing switch did you use?

I used a two pole ON-ON switch. The pump connections on the two common terminals, the supply negative and positive from the flush controller each go to diagonally opposite terminals on the switch. The back of the switch looks like this :

 

 

       +ve from controller      X            X   -ve supply

 

               +ve pump             X            X   -ve pump

 

                  -ve supply          X            X    +ve from controller

 

If the middle contacts are connected to the upper set, the pump works normally/ If the middle contacts connect to the lower set, the p[ump power connections are reversed.

 

 

Switch was one of them : 15A 250VAC 6 Pin DPDT ON-ON Toggle Switch+Waterproof Cap Dashboard Boat XT-22A | eBay

Edited August 9, 2021 by Iain_S

[ditchcrawler]

3 hours ago, Tracy D'arth said:

No moving parts in a portaloo , its just a tank that the emptier's vac pump empties.

DC switches need to have a heavy current rating due to the break arc. A switch that will cope with 10 amps on AC will fail prematurely at 10 amps on DC.

So I would suggest one rated at 10 amps minimum DC .

It doesn't need to "Switch" the DC if the switch is operated with the pump off

2 hours ago, David Mack said:

I agree its no problem for the particular portaloo operator. Presumably they put the notice there to avoid things being left on the floor as there is no bin. But it may create a mindset in the general public that it is OK to put that sort of thing down the toilet. And that is distinctly unhelpful for those with toilets that can't tolerate things which aren't bodily waste or cheap toilet paper.

The general public have that mindset already as they flush anything that will go away down their domestic loo

[Bargebuilder]

You are probably aware of this, but just in case not:

 

Although Tecma macerating loos are excellent and possibly the least likely of all boat toilets to block, they do, or at least did, have an Achilles heal.

 

When a Tecma's evacuation pump spins but the full pan doesn't empty and just a few bubbles appear, it can be due to an air lock in the rubber 's' shaped waste discharge pipe at the point where it joins the macerator pump inlet.

 

On early models, because I think they may have spotted the issue and corrected it, there is a tiny vent tube in the waste discharge pipe that vents the air so that when the bowl fills with water, the pump fully primes at the same time. If this tiny vent pipe blocks, the pump chamber doesn't fill properly with water, so the macerator disc spins in air and there is no suction at the bowl. The result is exactly as the original poster described.

 

My one used to block fairly regularly and unblocking it was a 'toilet out' job and not pleasant. I removed the original vent tube and replaced it with one long enough to run behind the bathroom wall to a position above the loo but easily accessible. After I had done that, when it blocked I could pressurise the tube, pushing the blockage out and thus allowing the air to escape as it should.

 

The toilet evacuated perfectly well with this tube in place, but if something wouldn't budge and the bowl began to fill, I would just block the end of the tiny tube with my finger and that would give a boost to the suction in the pan.

 

Eventually, after the so called sanitary hoses began to pong yet again and I became bored with occasional blockages and constantly having to pump out, I made and installed a separating loo and life was much sweeter and easier after that.

 

 

[Idle Days]

11 hours ago, Iain_S said:

I used a two pole ON-ON switch. The pump connections on the two common terminals, the supply negative and positive from the flush controller each go to diagonally opposite terminals on the switch. The back of the switch looks like this :

 

 

       +ve from controller      X            X   -ve supply

 

               +ve pump             X            X   -ve pump

 

                  -ve supply          X            X    +ve from controller

 

If the middle contacts are connected to the upper set, the pump works normally/ If the middle contacts connect to the lower set, the p[ump power connections are reversed.

 

 

Switch was one of them : 15A 250VAC 6 Pin DPDT ON-ON Toggle Switch+Waterproof Cap Dashboard Boat XT-22A | eBay

 

Thank you for your comprehensive reply. I have ordered a switch.