Princess 45 grey water tank stopped working

Soul_dancee

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Hi every one,

Any thoughts and ideas on how to fix the grey water tank (the water pump keeps getting blocked by hair and dirt from the two toilets i have)

I notice that there is no fliter to clear the water before going to the tank. I am not sure if there is a filter for that purpose.


The picture attached shows the grey water tank.

Best Regards
 

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Whatever you've got (toilet, pipes, pump, macerator, etc.) will need be taken apart, cleaned out of all the gunk and reassembled. It might be necessary to replace some of the pipes - over time they get a build-up reducing their internal diameter. But you can bang them against a wall or on the pontoon to dislodge all that and reuse them.

And when you've done that stop any hair & dirt(?) and bog roll and wet wipes, etc. getting in there in the first place. Only what comes out of your body should be going down the toilet. Have a little pedal bin in the head for people to put their bog roll, etc. in...
 
You’d have to rinse super well afterwards, but Caustic Soda is a great unblocker and line cleaner in my view. But very acidic so needs flushing and disclosing of carefully.
 
You’d have to rinse super well afterwards, but Caustic Soda is a great unblocker and line cleaner in my view. But very acidic so needs flushing and disclosing of carefully.
Caustic Soda is not acidic - it is alkaline (Sodium Hydroxide), and any first aid required and disposal should reflect this.
 
The OP said grey water not black so I suspect it's hair etc from the showers and sinks, nothing to do with the toilets. My grey tank has a stainless mesh inside that catches hair etc, not sure if you could fit similar.
 
Correct - I have the same tank on my P45, we have never had any issues, it only takes water from basins and showers in the head, no black water. On mine the tank also receives condensate from the AC unit in the master cabin.

I have not had any issues with blockages, if you want to prevent hair entering the pipes which are relatively short, you can remove the two timber floor grates below each shower and insert a mesh or screen to prevent hair entering.

It is very easy just to remove the lid and clean from time to time.
 
The OP said grey water not black so I suspect it's hair etc from the showers and sinks, nothing to do with the toilets.
Agreed - in fact, I think the black water tank is to the left in the photo.
Our Princess 67 grey water tank is bigger than the one in the photo but it looks like it works the same way.
Under the removable plastic transparent top is a standard Rule bilge pump - fitted at the bottom of the tank.
By default, Princess use the standard bilge bump float switch to clear the tank as it fills.
IIRC, there is also a non return valve in the discharge pipe which discharges above the waterline.
These tanks can get blocked and are the source of smells that most people would think come from the toilets.

My grey water tank blocked within 6 months of the delivery (new) of the boat.
Rather than complain and have the issue go on for years, I changed and rewired the float switch to a "High - Low" switch that I bought from Wema.
I also fitted a switch in parallel to "trigger" the "High - Low" switch thus emptying the tank when we leave the boat.
The result is that grey water builds up in the tank and discharges more water each time than the old Rule bilge pump switch.
I have continued to use the old Rule pump but I am paranoid that it will fail sometime so I have a spare "lined up" - just in case.
Even with this, I have to often take the cover off and rinse it out with a hose to keep the tank clean and free from smells.
I use a disinfectant during cleaning which helps to break down the blockages and makes it all smell better.
As a result, I don't get as much hair blockage as the OP seems to be getting.

The OP may be able to do the same that I've done but, as I said above, my tank is bigger.

This is a photo of mine:-
Note the Wema "High - Low" switch fitted in the plastic top of the tank.
As the float sises up the black shaft, it trips a high level and switches the pump on until the low level is reached thus pumping more water each time.

IMG_1805e.resized.jpg
 
If the OP has a similar vintage P45 to mine , the only fittings left and right of the tank would be sea-cocks, my much larger black tank is located in a different compartment, below the galley floor.

I would just fit mesh strainers to the outgo in each head to trap hair, not that I have any to worry about....!
 
This is one of the first things I check when opening up the boat! I always shut off the head sea-cocks close by, it then takes a couple of minutes to run the basin and observe the pump is operational. When I close the boat down, I just run the basins again and insert some chemical to keep the tank chlorinated and neutralise smells.

I was thinking of a high/low level float switch to reduce motor starts and in case the existing float switch fails, to bring up an alarm, but the tank seems to work well as is.

I had a real problem with the tank to the master cabin on my F43, which was located low down in the bilges, they sized the tank perfectly so that when the pump discharged, they was sufficient volume in the discharge pipe to slowly drain back through the non-return valve into the tank and activate the float switch again. Never ending cycle. Solve that by working out the volume of water held in the pipe and increasing capacity of the tank. Always left a volume of water drained back which was not ideal...!
 
Correct - I have the same tank on my P45, we have never had any issues, it only takes water from basins and showers in the head, no black water. On mine the tank also receives condensate from the AC unit in the master cabin.

I have not had any issues with blockages, if you want to prevent hair entering the pipes which are relatively short, you can remove the two timber floor grates below each shower and insert a mesh or screen to prevent hair entering.

It is very easy just to remove the lid and clean from time to time.


Thanks for the great comments

I am actually thinking about putting a mesh, i just didn't figure the best way yet.

Is it possible to post some pictures of urs?

Thanks
 
Agreed - in fact, I think the black water tank is to the left in the photo.
Our Princess 67 grey water tank is bigger than the one in the photo but it looks like it works the same way.
Under the removable plastic transparent top is a standard Rule bilge pump - fitted at the bottom of the tank.
By default, Princess use the standard bilge bump float switch to clear the tank as it fills.
IIRC, there is also a non return valve in the discharge pipe which discharges above the waterline.
These tanks can get blocked and are the source of smells that most people would think come from the toilets.

My grey water tank blocked within 6 months of the delivery (new) of the boat.
Rather than complain and have the issue go on for years, I changed and rewired the float switch to a "High - Low" switch that I bought from Wema.
I also fitted a switch in parallel to "trigger" the "High - Low" switch thus emptying the tank when we leave the boat.
The result is that grey water builds up in the tank and discharges more water each time than the old Rule bilge pump switch.
I have continued to use the old Rule pump but I am paranoid that it will fail sometime so I have a spare "lined up" - just in case.
Even with this, I have to often take the cover off and rinse it out with a hose to keep the tank clean and free from smells.
I use a disinfectant during cleaning which helps to break down the blockages and makes it all smell better.
As a result, I don't get as much hair blockage as the OP seems to be getting.

The OP may be able to do the same that I've done but, as I said above, my tank is bigger.

This is a photo of mine:-
Note the Wema "High - Low" switch fitted in the plastic top of the tank.
As the float sises up the black shaft, it trips a high level and switches the pump on until the low level is reached thus pumping more water each time.

View attachment 125416

Looks like a good idea with the high low, i have 2 questions though.

1. It's not clear where is ur pump in that picture.

2. How do u manage to stop hair from entering the pump?
 
Here’s a proprietary sump box for a bath room shower .
Not a clear pic but running length ways on the right under the green sticker is a mesh filter which collects the hair .
The white manifold is the IN .

A yearly pop off the lid via 4 screws suffices to clean it .

12CD46CF-C928-4541-8F60-2CC987C9BDC8.jpeg
 
Looks like a good idea with the high low, i have 2 questions though.

1. It's not clear where is ur pump in that picture.

2. How do u manage to stop hair from entering the pump?
The pump is at the bottom of the tank.
I think it is the same in your case.

Here is a photo that I took once before cleaning so you can see that it stays fairly clear of hair.
What have you got in the water outlets from the showers.
We do get some hair collecting in the bottom of the shower outlets which can be picked out easily when cleaning the showers.

DSC07982.resized.jpg

Just as well that we haven't moved the discussion on to black tanks!!!
 
A friend of mine used a single switch with a timer (20 seconds from memory).
He positioned the switch at the top of the tank which tripped when the tank was full.
The 20 seconds timer was enough to empty the tank so he didn't need a low level switch.
The beauty of his solution was that he found a proximity switch which detected the water level from the outside of the tank.
He said that the switch was very reliable and, of course, it doesn't get wet.
If you are interested, I could contact him and I'm sure he will tell us the name/make of the switch.
He used to post a lot on this forum so I'm sure he would help with the name.
 
Thanks for the great comments

I am actually thinking about putting a mesh, i just didn't figure the best way yet.

Is it possible to post some pictures of urs?

Thanks

Can do - but not until next out on the boat - 28 December...!

The tank size, operation and quality of the grey tank is good on the P45, just renew the pump and float switch, flush and clean the tank and pipes if you like, fit the mesh to the shower outgo's and forget it - mind you, I shall fit a high level alarm at some stage....!
 
A friend of mine used a single switch with a timer (20 seconds from memory).
He positioned the switch at the top of the tank which tripped when the tank was full.
The 20 seconds timer was enough to empty the tank so he didn't need a low level switch.
The beauty of his solution was that he found a proximity switch which detected the water level from the outside of the tank.
He said that the switch was very reliable and, of course, it doesn't get wet.
If you are interested, I could contact him and I'm sure he will tell us the name/make of the switch.
He used to post a lot on this forum so I'm sure he would help with the name.
I was wrong, the level switch is fitted inside the tank - not on the outside and it only runs for 8 seconds.
But it might still do the job.
One of these, I think:-
Float Switch Replacement 12v Water Witch 101
 
I guess just a simple filter on top of the drain can stop hair
 

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