Maceratior Toilet

[quovadis]

Could an expert in the toilet field please advise me on what is wrong with my Vetus toilet that has just been installed and has flow back.  The flow back is not clear water, it is sewage water without solids.  I have read the installation guide and it looks like to me it is either the non return valve or siphoning.  I have the guy who installed it on call but I want to have an idea of what it might be.  Please help

[NMEA]

Is the lavvy below the holding tank?

[quovadis]

yes

 

[Chewbacka]

Does it happen quickly?  On my toilet the discharge pipe goes about 2ft above the toilet discharge outlet then slopes down to the tank and discharges into the top of the tank.  If I flush it just once after a few hours there is certainly some discolouration of the water in the toilet bowl.  However in normal use it will get flushed again before that happens, so is not a problem.  I think it is probably normal.  

I am no expert on toilets, but if you tell us exactly what yours does and the pipe layout, you may get some helpful replies.

Edited April 15, 2017 by Chewbacka

[NMEA]

The joker valves are not really up to coping with any head, we normally install an extra NRV if the tank is above the lavatory pan.

[rustydiver]

On mine i have a non return valve, like a rubber flap thing, can you get new valves i dint think mine is fully working.

Tank below the toilet. Starting to get a slight whiff come from the toilet. noticed it more when when had the toilet emptied and after a few days off using it. I use the green no oder stuff.

[NMEA]

Joker valves get calcified and don't close fully which allows smells back up. A little acid treatment to remove the calcified deposits works well.

[quovadis]

As a total Greenhorne I will try to explain.

 

Firstly thank you NMEA What type of NRV (where do I buy it) and where do I fit it ?  Will it put more pressure on the macerator and pump

Secondly if my sewage tank is full will this cause the feedback to increase

Thirdly the toilet has just been installed but has had feed back. I have switched the clear flush water off and the feed back is half the toilet bowl with flush water off.  As far as the pipework goes I dont know.  In my front wardrobe  there is a large vent that leads to an outside vent and I presume the other one comes from the tank  This vent is at at the boats roof level.  The sewage tank is in the bow.  I will investigate pipes further. 

[NMEA]

Personally if it's a new install I would call back the installer and have an NRV fitted as close to the pan as practical. Minor though noticeable back flow is a perennial problem when there is any head of effluent above the pan but it is easily solved and the reason we always fit an NRV in such scenarios so we are not called back to rectify it.

[Sea Dog]

Having to return just once to rework a boaty macerator toilet ought be enough for anyone worth his salt to get it right first time, every time, ever after!  I'm thinking you either  employed a newbie or a numpty but, whichever it is, he needs to come back to put it right - or his boss does. 

Incidentally, I think everyone else is thinking about a little dark water lurking in the bottom of the hole; your half a bowl full is pretty extreme.

[quovadis]

 

Hi NMEA What type of NRV (where do I buy it) and where do I fit it ?  Will it put more pressure on the macerator and pump

Do most chandlers have them.

 

Edited April 15, 2017 by quovadis

[nb Innisfree]

On Innisfree we were very generous with flushing water to keep water above toilet reasonably clean and prevent bacterial smells developing. 

Also once a month or more often we soaked the toilet bowl, pipe and NRV in hot water and descaling acid, left overnight to ensure proper descaling. Stopped any smells. 

[jddevel]

I too would like to know more about non-return valves in the sanitary system. I have a Vetus macerator toilet which has a 19mm outlet pipe to holding tank. From what I have read 38mm seems to be the size of valve used. So the question is if a NRV is to be used will 19mm be satisfactory or should I increase the size of pipe to accommodate the valve?

[NMEA]

19mm does seem rather small for sanitation use even as a breather, we would noally use 1 1/2" but 19mm NRVs are available.

[NMEA]

This is what we use, they work well enough and are very easy to service as they will inevitably need to be

http://www.aquafax.co.uk/html/product_specification.asp?ID=8924

[Chewbacka]

Thanks for that, I might just order one if I can get the financial controllers agreement - I will wait till she is well into her Easter egg and in a good mood before asking.......

[jddevel]

Whoops. Pipe size is  25mm not 19mm!!!

[NMEA]

Doesn't really matter as all fittings are available in 1" or 25mm

[Machpoint005]

15 hours ago, NMEA said:

Doesn't really matter as all fittings are available in 1" or 25mm

Does the 0.4mm difference matter?