Nasty niffs from pump out

[Tony Brooks]

23 minutes ago, blackrose said:

Follow Tony's advice and identify what type of toilet it actually is. Nobody can really tell you where to install the fan until they have a better idea of your existing venting system. 

 

A computer fan left on continuously will vent the tank headspace and stop it smelling when not in use, but as Tony says it may not be powerful enough to prevent smells coming back into the boat when the toilet is in use. The basic principal is that when you dump solids or liquids into the tank the same volume of smelly air in the tank is displaced and has to escape. If the path of least resistance is straight back up through the open toilet bowl then that's what will happen.

 

So if you do install a computer fan then rig it up temporarily because if you find it isn't powerful enough you may need to replace it with a bilge blower that you would only switch on when using the toilet. I have done this on my Thetford cassette toilet (which is basically a mini-dump through toilet) and it works very well. But a computer fan is only a few quid so it's worth trying first.  

 

All true, but if there is only one vent pipe the fan/bilge blower will reduce the pressure in the tank and then, although running, do nothing. It would need a second vent as far away from the first as possible so the fan/blower evacuated the niffy air from the tank and can then draw clean air into the tank so it is the clean air the "blows back" through the pan.

[David Mack]

I had in mind a tank with two vents at opposite ends, one fitted with a bilge blower that sucks air out, controlled by a timer which runs for a few minutes after the toilet has been used - similar to domestic shower fans. Could even connect it to a proximity switch so the fan starts up when anyone comes near the loo.

Edited August 28, 2022 by David Mack

[IanD]

2 hours ago, David Mack said:

I had in mind a tank with two vents at opposite ends, one fitted with a bilge blower that sucks air out, controlled by a timer which runs for a few minutes after the toilet has been used - similar to domestic shower fans. Could even connect it to a proximity switch so the fan starts up when anyone comes near the loo.

With two vents at opposite ends -- especially if on opposite sides of the boat -- there's much better ventilation through the tank, so a fan is unlikely to be needed.

[Spudwynk]

On 27/08/2022 at 13:35, blackrose said:

Follow Tony's advice and identify what type of toilet it actually is. Nobody can really tell you where to install the fan until they have a better idea of your existing venting system. 

 

A computer fan left on continuously will vent the tank headspace and stop it smelling when not in use, but as Tony says it may not be powerful enough to prevent smells coming back into the boat when the toilet is in use. The basic principal is that when you dump solids or liquids into the tank the same volume of smelly air in the tank is displaced and has to escape. If the path of least resistance is straight back up through the open toilet bowl then that's what will happen.

 

So if you do install a computer fan then rig it up temporarily because if you find it isn't powerful enough you may need to replace it with a bilge blower that you would only switch on when using the toilet. I have done this on my Thetford cassette toilet (which is basically a mini-dump through toilet) and it works very well. But a computer fan is only a few quid so it's worth trying first.  

Thanks

We think the smell is going out the external vent not coming back up the loo which then comes in the open porthole hoppers and makes the bedroom pong. Hubby is at the boat today so photo will be forthcoming shortly

[MtB]

17 hours ago, David Mack said:

I had in mind a tank with two vents at opposite ends, one fitted with a bilge blower that sucks air out, controlled by a timer which runs for a few minutes after the toilet has been used - similar to domestic shower fans. Could even connect it to a proximity switch so the fan starts up when anyone comes near the loo.

 

 

So anyone on the towpath when this happens gets a blast of stinky air?!

 

 

[Tonka]

4 minutes ago, MtB said:

 

 

So anyone on the towpath when this happens gets a blast of stinky air?!

 

 

Same as if you are by a septic tank when the toilet is flushed. 

Same as if you are by a toilet vent pipe when the toilet is flushed

Not sure what your point is

[Ex Brummie]

7 minutes ago, MtB said:

 

 

So anyone on the towpath when this happens gets a blast of stinky air?!

 

 

So C&RT T&C@s should include a requirement to moor with the vent away from the bank.🥴

[Tony Brooks]

33 minutes ago, MtB said:

 

 

So anyone on the towpath when this happens gets a blast of stinky air?!

 

 

 

Initially probably, but no more so than when a boat operates their vacuum or maccerator toilet and expels fetid air from the tank. In fact probably less because once up and running there should be less foul gasses in the tank to be expelled because of the constant change of air. It may also be less because the constant supply of oxygen to the effluent surface should encourage aerobic bacteria to breed and thus reduce the smelly anaerobic ones.

[Momac]

I dont notice any odours from the holding tank on my boat . Nor generally  from others to be honest.

But a little used boat near us did develop a pong  . A visit to the pump out sorted it out.

Also had a boat nearby develop a pong but that was a gassing battery.

 

[David Mack]

On 28/08/2022 at 18:08, IanD said:

With two vents at opposite ends -- especially if on opposite sides of the boat -- there's much better ventilation through the tank, so a fan is unlikely to be needed.

Part of my thinking was to have a slight negative pressure in the tank when the blower is running, so that when the dump-through valve is opened less smelly tank air will be displaced into the bathroom.

[Momac]

I think the dump through arrangement quite disgusting.

Why not have a toilet that can have flush water in the bowl to keep tank smells in the tank.

 

No smells at all over the recent hot weather means I am even more convinced enzyme chemicals work to kill tank smells. But you should not mix chemicals in the tank as they may work against each other .

 

Edited August 30, 2022 by MartynG

[Spudwynk]

We definitely get quite a bit of water running through ours but the toilet arrangement looks like the one Tony posted of a dump through 

[Tonka]

4 minutes ago, Spudwynk said:

We definitely get quite a bit of water running through ours but the toilet arrangement looks like the one Tony posted of a dump through 

Can you post a photo of your toilet please.

 

51 minutes ago, MartynG said:

I think the dump through arrangement quite disgusting.

Why not have a toilet that can have flush water in the bowl to keep tank smells in the tank.

 

No smells at all over the recent hot weather means I am even more convinced enzyme chemicals work to kill tank smells. But you should not mix chemicals in the tank as they may work against each other .

 

A dump through is not disgusting. It is easier to clean the tank. A macerator toilet is disgusting.

[Tony Brooks]

58 minutes ago, Spudwynk said:

We definitely get quite a bit of water running through ours but the toilet arrangement looks like the one Tony posted of a dump through 

 

If we accept that is the case then you know what to do. Avoid conventional Blue but expect even nastier niffs for the next few pump outs. Try some of the product recommended above. Then locate the tank breather, assuming the builder fitted one and ensure it is at least 22mm diameter, then work out how to fit another at the opposite end of the tank. If none of that works make up a computer fan in a box that you put into one breather to expel air. The alternative is fitting another and probably more expensive semi-convetional toilet or changing to a cassette type toilet.

 

I am afraid that unless you are wealthy you will find that boat owning almost demands a lot of DIY work. Be it repairing, diagnosing, or finding out what you have and where, and how it works. We can help with some of that and are more than happy to, but we do need the basic information. Every boat should be considered as a one-off and different to all the rest. Photos always help.

 

Right - the water running through the toilet.

 

The toilet should start with a modest amount of water in the bowl and if that drains away the rubber seals that press on the flap thing/half ball need removing, cleaning and regreasing with silicon grease or renewing. It is also as well to make sure the ball/flap ting is nice and clean. I am not going to try to tell you how to do this until I can see exactly what toilet you have but in most cases it is just undo a large clamp affair.

 

You maker the deposit and then push the lever down. This does two things. It opens the flap and also opens the water valve. Water will continue to flow until you release the lever.

 

When you release the lever a modest amount of water continues to flow for a few seconds to make a water seal in the bowl.

 

If water continues to flow then one of the following is likely.

The water valve is faulty or mall adjusted.

The lever part that operates the valve is bent or maladjusted.

The lever fixes onto a gear mechanism that operates the flap, the gears are plastic and when they break the lever may not fulley return so the water is never fully shut off.

Edited August 30, 2022 by Tony Brooks

[ditchcrawler]

55 minutes ago, Tonka said:

 A dump through is not disgusting. It is easier to clean the tank. A macerator toilet is disgusting.

The only time we get a smell from our dump through is when you hold the ball open to give the seal a good clean. The share boat we had there was no seal between the tank and  the base of the toilet. When I did ours I had a stainless steel tank and a threaded flange welded where the toilet goes on the tank, the adapter flange is then screwed into the flange and sealed before being supported by the wooden cover. Another thing I did was to seal the bowl overflow as that can give a direct connection to the tank.

 

If the ball seals are in bad condition so that the bowl doesn't hold water it will also smell.

Edited August 30, 2022 by ditchcrawler

[ditchcrawler]

On 27/08/2022 at 14:02, Tony Brooks said:

 

All true, but if there is only one vent pipe the fan/bilge blower will reduce the pressure in the tank and then, although running, do nothing. It would need a second vent as far away from the first as possible so the fan/blower evacuated the niffy air from the tank and can then draw clean air into the tank so it is the clean air the "blows back" through the pan.

I am still not convinced he has a drop through for this statement

 

"When we flush we hear a whirring under the bed going"

[Tony Brooks]

9 minutes ago, ditchcrawler said:

I am still not convinced he has a drop through for this statement

 

"When we flush we hear a whirring under the bed going"

 

I agree, but do they know where their domestic water pump is located. I don't know why they don't post a photo of the toilet assembly in place and its control panel if it has one.

[Spudwynk]

Definitely don't have a control panel. Waiting for hubby to send me photo as I wasn't at the boat this weekend. Not cc's so have to wait for a week to take a new photo

[Tonka]

1 hour ago, Tony Brooks said:

 

If we accept that is the case then you know what to do. Avoid conventional Blue but expect even nastier niffs for the next few pump outs. Try some of the product recommended above. Then locate the tank breather, assuming the builder fitted one and ensure it is at least 22mm diameter, then work out how to fit another at the opposite end of the tank. If none of that works make up a computer fan in a box that you put into one breather to expel air. The alternative is fitting another and probably more expensive semi-convetional toilet or changing to a cassette type toilet.

 

I am afraid that unless you are wealthy you will find that boat owning almost demands a lot of DIY work. Be it repairing, diagnosing, or finding out what you have and where, and how it works. We can help with some of that and are more than happy to, but we do need the basic information. Every boat should be considered as a one-off and different to all the rest. Photos always help.

 

Right - the water running through the toilet.

 

The toilet should start with a modest amount of water in the bowl and if that drains away the rubber seals that press on the flap thing/half ball need removing, cleaning and regreasing with silicon grease or renewing. It is also as well to make sure the ball/flap ting is nice and clean. I am not going to try to tell you how to do this until I can see exactly what toilet you have but in most cases it is just undo a large clamp affair.

 

You maker the deposit and then push the lever down. This does two things. It opens the flap and also opens the water valve. Water will continue to flow until you release the lever.

 

When you release the lever a modest amount of water continues to flow for a few seconds to make a water seal in the bowl.

 

If water continues to flow then one of the following is likely.

The water valve is faulty or mall adjusted.

The lever part that operates the valve is bent or maladjusted.

The lever fixes onto a gear mechanism that operates the flap, the gears are plastic and when they break the lever may not fulley return so the water is never fully shut off.

If it is a Mansfield dump through pushing the lever down opens valve and ball to flush toilet. If you lift the lever the water should fill the bowl 

[ditchcrawler]

2 hours ago, Tonka said:

If it is a Mansfield dump through pushing the lever down opens valve and ball to flush toilet. If you lift the lever the water should fill the bowl 

And if you look in the bowl with the leaver pressed down you can see straight into the holding tank and see how full it is. NOTE, Water will normally flow all the while the peddle is depressed

[Tonka]

16 minutes ago, ditchcrawler said:

And if you look in the bowl with the leaver pressed down you can see straight into the holding tank and see how full it is. NOTE, Water will normally flow all the while the peddle is depressed

So turn the water pump off and get a torch to see how much sugar harry is in there

[Laurie Booth]

On 13/08/2022 at 22:42, Spudwynk said:

Thanks everyone. Yes there is a pedal which we push and it seems like it sumps through but I also think k there's is a vacuum element to it in the way the way seems to be sucked down into the tank. 

Why not ask the people who owned the boat before you

[Spudwynk]

21 minutes ago, Laurie Booth said:

Why not ask the people who owned the boat before you

Because it was sold to an intermediary who sent her for a few weeks to bridgehouse marina to do her up to sell (as it was a slow seller) and therefore doesn't know much about the onboard systems

 

Anyhow the photos have finally arrived you'll all be pleased to know

[Alan de Enfield]

Well, its not what I would call a 'dump-Thru' (where the toilet sits directly on top of the holding tank)

 

The "output" is piped away from the toilet to a tank hidden away somewhere.

 

 

 

[Tony Brooks]

I don't think it is a dump through because of that big corrugated plastic hose. Dump troughs do not have those. The base looks rather small to contain a macerator and motor so probably a vacuum toilet. If any effluent lies in that hose you are likely to gets smells through the hose wall and thus inside the boat and the first photo you put up showed effluent and paper lying below the bowl.