Battery's Or Bog??

[Mowjo]

Right folks! I've been thinking of putting a pump out toilet on my Birchwood, the ideal place for the tank is directly behind the toilet in the engine bay and it would be an easy job! the problem is where I want to put the tank is where my three battery's live, so I have two choices, move the battery's to the back of the boat, giving me something like a 2.5mtr run of cable to my  main switch or put the tank in the back giving me a 2.5 mtr run of main waste pipe, my thinking is move the battery's as 2.5mtrs is a long way to pump stuff, but I'm unsure if the battery cable run would be too long, any advice????

Frank,,,

[MauriceMynah]

Are there no other options as to where your batteries could live? The toilet tank is best as near to the loo as possible.

 

Edited to add that amps will run along a wire better than turds will run along a pipe. Something to do with resistance I believe.

[tjg1677]

use 300 amp cable and there will be no problems with the length of the cable run and voltage drop. To be fair, 2.5 metres is not really an overly long run of cable, so should be fine.

hope this helps

Trev.

[Mowjo]

Thanks Folks! I did think I'd have to uprate the cables, question now is do I tell the wife it's an easy job or not? as it's her that keeps nagging for a pump out toilet,,,

[grendel]

you will need new cables to move the battery, buy the bigger size, and tell the wife that was what they had on offer, running 2.5m of cables should be easier than 2.5m waste pipe, tell her its a medium difficulty job, then get kudos when you finish quicker than the estimated time (I always double the time estimate when telling the wife - just to be on the safe side.

[Mowjo]

I'll do my Usual loads of swearing and saying it was Ok before so why are we spending all this money, make it look much harder than it is, tell her I need a new drill or some other powertool to do the job, she'll just say get it then if you need it, and I win all round, the Porta Potty is fine in the marina we have a Porta point, it's when we are out for any length of time, we normally have to go back to Broadsedge to empty it, baffles me that with so many boats having Porta loos there arn't many places to empty them,,

 

[Baitrunner]

Pee in the bushes and flush less. 

Buy the power tools though. You know you MIGHT need them one day. 

I would agree the power cables might be easier to run than the waste pipe. Although on my old boat I had a manual pump toilet to tank that must have been over 2.5 m away and it wasn't a problem pumping the Richards to their sleeping quarters. 

[dnks34]

Im sure you have thought this through but thinking about moving any batteries to a new location on my boat would be nothing short of an absolute nightmare and probably cost a small fortune in battery cable.  A lot more than 2.5m of waste hose anyway.  

Would it really be such an issue? One of my tanks has got to be over 1.5m away from the toilet and it doesnt cause any issues, would another metre change that much. 

It might just require a few extra pumps to ensure its reached the tank.

Obviously if theres no way of concealing the waste pipe the distance to the tank its a problem 

[Viking23]

3 hours ago, Mowjo said:

... move the battery's to the back of the boat, giving me something like a 2.5mtr run of cable to my  main switch...

To compare like with like, the new cable run to the switch is 2.5 metres, but what is the length now?

Can you also consider repositioning the isolator switches, to reduce the cable run?

Voltage drop based on cable size, length and current passed is quite easy to work out, but don't forget to include the losses in the black return cable too.

An an electronic engineer I would opt  for moving the batteries provided that they are in a cool and well ventilated space. Refer to BSS for correct installation.

A shorter pipe full of **** will be easier to clear than a compacted long pipe full of **** which is likely to block more often. If you opt for the long pipe, make sure you have full access to both ends of the pipe. 

Smells do permeate through plastic, the longer the length, the greater the smell.

[Viking23]

4 hours ago, tjg1677 said:

use 300 amp cable and there will be no problems with the length of the cable run and voltage drop. To be fair, 2.5 metres is not really an overly long run of cable, so should be fine.

hope this helps

Trev.

I think that stating a 300 Amp cable without knowing the currents required, cable lengths and acceptable voltage drops is a bit of a guess, it might well be right, but better to have a couple of simple calculations to hand to justify the new cable.

You also need to consider if an inverter is or may be installed later, that the voltage drop could be unacceptable to the inverter, and may require that the engine has to be run, just so the inverter can start up.

Sounds familiar in hire boat installations, doesn't it. ?... That might be a case of inadequate wire sizes giving too much of a voltage drop, or low battery capacity. I am not implying it could be an unsafe installation, just that the voltage drop for inverters could stop them running unless the batteries are in tip top condition.

[ZimbiIV]

Have a look at Tectanks site you may find a tank that can fit around the battery area or they will make one, a very helpful company to talk to.

I have always understood it is the straight run to the pump out point that is more important no bends equal better emptying.

paul

Ps fit a level indicator, you will have one thing less to worry about while sat reading the paper.

[Bound2Please]

Our old Birchwood had the tank under the batteries frank

Charlie

[Vaughan]

1 hour ago, ZimbiIV said:

have always understood it is the straight run to the pump out point that is more important no bends equal better emptying.

paul

X-LAX!

"Cleans like a white tornado!"

[Timbo]

I will soon face this same dilemma of where to put the sh waste tank. Fortunately I have a bit more space to play with and the batteries will still fit in the engine bay, but the tank is going to have to go in the engine compartment. Now it may just be the way my mind works but...with the sh waste tank sitting on top of the engine won't this warm up the sh contents? Isn't there some sort of chemical reaction going to take place if the whole thing is heated up? So should something untoward happen I'm liable to get covered in short sharp HOT shower?

[dnks34]

Do you mean a Shower of Shhh  

[BroadScot]

Careful now, it is a family forum! 

Iain

[Mowjo]

The problem is that if I put the holding tank in the back  I'd have to have one made to fit, fitting it where the battery's are I can use a standard tank, I could move the master switch but then I'd have to replace a lot more cable and not just 2.5 of each colour, luckily my boat isn't power hungry, lights are all LED, Fridge is quite low amp draw, TV is low amp draw, water pump is normal, and there's no chance I'll ever fit an inverter, never seen the need for one, it's possible I might even be able to re-position the battery's and fit a tank alongside them, as there's plenty of room, it's a matter of finding the right size tank without having one made, and I just thought of another problem, in my cockpit there is only around 3ft of deck to use and that over the battery's, the other 6ft is flush with the hull side so fitting it in the back, I'd have nowhere to fit the pump out fitting, it now looks that if I fit one it can only go where the battery's are,,

[JanetAnne]

9 hours ago, MauriceMynah said:

Edited to add that amps will run along a wire better than turds will run along a pipe. Something to do with resistance I believe.

Beautifully put 

9 hours ago, tjg1677 said:

use 300 amp cable and there will be no problems with the length of the cable run and voltage drop. To be fair, 2.5 metres is not really an overly long run of cable, so should be fine.

hope this helps

Trev.

agreed

 

Just to add, we have one of our tanks just over 12ft away from the loo. Never been a problem - so far!

Someone mentioned smell from pipe and the more pipe you have the more smell is possible. Have a look at the Butyll hose from ASAP (I'm sure its available elsewhere as well). This stuff is brilliant. Very easy to use and seals perfectly. Not a whiff in use which is a vast improvement over the commonly used white plastic based hose.

[JanetAnne]

2 hours ago, Timbo said:

I will soon face this same dilemma of where to put the sh waste tank. Fortunately I have a bit more space to play with and the batteries will still fit in the engine bay, but the tank is going to have to go in the engine compartment. Now it may just be the way my mind works but...with the sh waste tank sitting on top of the engine won't this warm up the sh contents? Isn't there some sort of chemical reaction going to take place if the whole thing is heated up? So should something untoward happen I'm liable to get covered in short sharp HOT shower?

What you need is an accumulator tank young Tim. If you can fit a demijohn type airlock to the tank in question you should be able to syphon all that, now flammable, hot air and collect it in the accumulator tank. With some careful plumbing this will allow you to direct said hot air to your hob giving you free gas for your cooking needs. Once its all installed, the space saved by no longer needing the more conventional gas cylinders can be turned into a 'safe area' where, with careful use of armour plating, you can protect yourself should the sh contents of the tank become too volatile. Hope this helps?

[grendel]

with careful plumbing you may be able to fit a collector into Uncle Alberts cabin too.

[Hylander]

15 hours ago, grendel said:

 tell her its a medium difficulty job, then get kudos when you finish quicker than the estimated time (I always double the time estimate when telling the wife - just to be on the safe side.

      Now you have let the cat out of the bag.       I shall view statements in the future of '  this is going to be a nightmare' in a different light completely.

[Mowjo]

We have to get our own back for all those clothes that suddenly appear in the wardrobe and you tell us Oh! I've had that ages, but forget you've left the price tag on it,,

 

[MauriceMynah]

Oh come on Mowjo. Just wait till they put it on for the first time and say...

...  "Oh come on love, you can't wear that old thing"

[ExUserGone]

23 hours ago, Mowjo said:

Thanks Folks! I did think I'd have to uprate the cables, question now is do I tell the wife it's an easy job or not? as it's her that keeps nagging for a pump out toilet,,,

Fit a sea toilet and tell her it's a pump out jobbie and that you get it emptied while she's not there to spare her the smell, that way you get in the good books and get to spend the pump out fee in the pub.

But don't moor on still water as she'll spot the evidence as it floats by.

[dnks34]

Its also worth considering what size of tank you are going to fit in as if its not a good size you will be spending a lot on pump outs.

We once fitted one of the smallish plastic tanks that a wroxham chandler sells to a boat that only had sea discharge and it seemed to fill up so quickly with just 2 people onboard it turned into a pain.  In the end it was only used for number 2s but still needed pumping out very regular.  Its suprising how much water is added to the waste in the flushing process. 

The boat we have now has 2 tanks and they will last easily a full 2 weeks with 2 onboard and a months worth of weekend visits easily infact they only get pumped out when we start to get a smell from them.