Grey water tank warning constantly flashing

[htrevor]

Hi

For the last few months the grey water tank full warning light on the control panel is almost constantly, annoyingly, flashing. For a few hours after emptying it stops but then carries on until emptying again.

I have tried the appropriate Elsan additive overnight, bleach and even 4 litres of cola after seeing one of your posts. My dealer in the Uk could not sort it and also Westfalia in Germany and they also sent me to another place when they couldn’t solve the problem. I then asked if they could disconnect the sensors completely so that at least it would no longer be flashing but they were unable to do that. Incredible. I would be grateful if anyone has an answer or a similar experience.

 

Trevor

 

Fiat Ducato Westfalia Amundsen 600d.

[bodach]

I had the same problem on my McLouis Lagan and had no problem getting it disconnected since I never needed it anyway.

[Brambles]

My McLouis used to do the same, stopped when I clean the tank externally between the contact connections and greased the connectors.

[Derek Uzzell]

As Trevor’s grey-water issue could not be resolved by the UK Westfalia agent, Westfalia in Germany and whoever Westfalia in Germany referred Trevor to, it’s reasonable to assume that whatever is causing the problem won’t be cured by a simple wipe-over of the outside of the motorhome’s grey-water tank.

 

There are several methods used for measuring how much fliud is in a grey-water tank - there might be a ‘float switch’ or ’screws’ inserted into the tank’s side - but In both those cases it OUGHT to be straightforward to disconnect the electrical wiring to the switch/screws and that SHOULD stop the ‘tank approaching full’ warning light illuminating on the control-panel.

 

I don’t know what grey-water tank contents-level measuring system Westfalia uses on its Amundsen 600d model, nor what control-panel is fitted. It may be that accessing whatever sensor is used to measure the grey-water tank’s contents is not easy - perhaps the tank is heavily insulated, or the tank needs to be detached from the vehicle to address the problem. (It might be helpful if Trevor said what explanation he was given as to why the false-reading warning-light could not be dealt with by 'disconnection'.)

 

A crude ‘fix’ might be to mask the flashing warning light with a small piece of opaque adhesive tape, but that might not be a practical solution if the control-panel is unusual.

 

(Trevor - I’m pleased that the ticking noise of your Westfalia’s diesel-fuelled heater has clearly not driven you nuts ;-) )

[flyboyprowler]

This is a problem we have experienced on our Niesmann, there has, as yet, been no permanent cure BUT, removing the sensor (ours unscrews from the top of the tank) and cleaning the sensor with clean water does the job, but only for a while. It also helps to rinse round the inside of the tank with fresh water on occasion, and that helps keeping the "full" light at bay. As we are still under guarantee, I am going to ask for a replacement sensor before the guarantee expires.

[Don636]

Sounds like mucky sensors inside the tank to me that need cleaning. Try filling the tank nearly full with a mixture of bleach and washing up liquid or some other cleaner then driving around for a good distance to slosh it all around then drain and flush a couple of times.

[Billggski]

Another possibility is a simple wiring fault, if the insulation has chafed at some point it will be making a contact and activating the light.

If this is so, changing the probe or even control panel won't cure it.

If you can run similar wiring from the sensor to the gauge to by pass the existing wiring you should be able to check.

Annoyingly complicated for a minor problem.

[Derek Uzzell]

In his original posting Trevor said

 

"I have tried the appropriate Elsan additive overnight, bleach and even 4 litres of cola after seeing one of your posts.”

 

There used to be a webpage provided by a water hygiene specialist that advised on the relative capabilities of agents that might be used to clean leisure-vehicle grey-water tanks. Soft drinks like Coca-Cola had minimal effectiveness (anything a human can drink without dying could hardly be expected to remove crud/scale from inside a plastic tank) and employing a strong bleach solution was the time-honored method.

 

Nowadays there are ‘friendlier’ commercial cleaning products from Dometic, Fenwick, Elsan etc. in fluid or tablet form and several YouTube videos.

 

https://tinyurl.com/t9ymcx5

 

However, it’s peculiar that, after Trevor has emptied the grey-water tank (90 litres capacity), the warning light stops flashing but starts to flash again soon afterwards. As Billggski says, the problem may be due to a wiring fault, but the fact that the warning light does stop flashing temporarily when the tank is emptied seems to indicate otherwise. (From Trevor’s earlier forum postings, I’m doubtful that he will wish to carry out ‘technical’ DIY trouble-shooting.) Putting a cleaning agent into the grey-water tank has failed to cure the problem, so masking the irritating warning light on the control-panel should be an instant 'cheap-and-nasty-but-effective' ploy.

 

I THINK an Amundsen 600D’s habitation electrics may be CBE-made. If that’s correct, it should be practicable to address the problem by disconnecting the plug on the CBE Distribution Box that is cabled to the grey-water tank sensors that (for a CBE system) would normally be a pair of ‘screws’ in the tank’s side near its top. If it’s very difficult to access the sensors on the grey-water tank, just pulling out a single plug on the Distribution Box should be much simpler and definitely stop the light flashing. Of course, if Westfalia had been bloody-minded and installed the Distribution Box where getting at it needed dismantling half the motorhome, that would be another matter...

 

[htrevor]

Brambles - 2020-02-19 3:40 PM

 

My McLouis used to do the same, stopped when I clean the tank externally between the contact connections and greased the connectors.

Thanks but my dealer at least tried that.

[htrevor]

Derek Uzzell - 2020-02-19 6:45 PM

 

As Trevor’s grey-water issue could not be resolved by the UK Westfalia agent, Westfalia in Germany and whoever Westfalia in Germany referred Trevor to, it’s reasonable to assume that whatever is causing the problem won’t be cured by a simple wipe-over of the outside of the motorhome’s grey-water tank.

 

There are several methods used for measuring how much fliud is in a grey-water tank - there might be a ‘float switch’ or ’screws’ inserted into the tank’s side - but In both those cases it OUGHT to be straightforward to disconnect the electrical wiring to the switch/screws and that SHOULD stop the ‘tank approaching full’ warning light illuminating on the control-panel.

 

I don’t know what grey-water tank contents-level measuring system Westfalia uses on its Amundsen 600d model, nor what control-panel is fitted. It may be that accessing whatever sensor is used to measure the grey-water tank’s contents is not easy - perhaps the tank is heavily insulated, or the tank needs to be detached from the vehicle to address the problem. (It might be helpful if Trevor said what explanation he was given as to why the false-reading warning-light could not be dealt with by 'disconnection'.)

 

A crude ‘fix’ might be to mask the flashing warning light with a small piece of opaque adhesive tape, but that might not be a practical solution if the control-panel is unusual.

 

(Trevor - I’m pleased that the ticking noise of your Westfalia’s diesel-fuelled heater has clearly not driven you nuts ;-) )

Hi Derek. Thank you for remembering about the problems I had with the diesel pumps ticking noise. Had the problem for along time which lessoned as the weather became warmer and also the fact that I could use electric only or a combination of electric and diesel in campsites, which I hadn’t realised. Should have noticed that there might have been a reason for it being called a Truma combi6. Anyway beginning of December I took my van to Westfalia in Germany for a check up and overhaul. Over a period of 6months I had a total of 6 floods in the van caused by the water pipes bursting. The pipes were very cheap and eventually Westfalia sent some better quality ones over and my dealer striped the old ones out and replaced them. End of problem but I took the van to Germany for a thorough check for any water damage. I also had asked them to look into the noisy diesel pump problems whilst there. They changed the pump for a newer model, or so they said and hey presto no more noise at all. In fact after Germany I was heading to Spain so that I didn’t have to listen to the pump so much but changed my mind because of the new quiet pump and did a 2 month tour of Sweden and Norway. I had a host of other problems which I got them to look at but eventually after a year and a half (from new) the van is working perfectly, well except for the waste water light but I will gladly accept that.

Anyway back to the current problem. There are two sensors on the side of the tank, they showed me in England and Germany. My dealer cleaned the sensors initially. In Germany they said that they could not just disconnect the sensors permanently. They tried to explain why but I could not understand them. As a last resort, yes, I thought about putting some tape across to mask the light but that would not be very easy as there are are many other warning lights in close proximity and it would look pretty cheap, like repairing broken spectacles with a band aid and also how would I explain it to a future potential buyer?

 

Kind regards

Trevor

 

 

[htrevor]

flyboyprowler - 2020-02-19 9:03 PM

 

This is a problem we have experienced on our Niesmann, there has, as yet, been no permanent cure BUT, removing the sensor (ours unscrews from the top of the tank) and cleaning the sensor with clean water does the job, but only for a while. It also helps to rinse round the inside of the tank with fresh water on occasion, and that helps keeping the "full" light at bay. As we are still under guarantee, I am going to ask for a replacement sensor before the guarantee expires.

Hi, Yes, Replacing the sensors was mooted by my dealers as a possible solution but anything from Westfalia takes 3 months to arrive so as I was going to Germany I decided to ask them to look at it there. Trouble was that once they emptied the tank the flashing stopped so I think they lost interest and I was on my way home by then.

 

Many thanks

[htrevor]

Don636 - 2020-02-19 9:31 PM

 

Sounds like mucky sensors inside the tank to me that need cleaning. Try filling the tank nearly full with a mixture of bleach and washing up liquid or some other cleaner then driving around for a good distance to slosh it all around then drain and flush a couple of times.

Hi, yes as I said I have tried various cleaning methods including bleach but not washing up liquid. Might try upping the bleach amount and add washing up liquid,

 

Many thanks

[htrevor]

Billggski - 2020-02-20 8:13 AM

 

Another possibility is a simple wiring fault, if the insulation has chafed at some point it will be making a contact and activating the light.

If this is so, changing the probe or even control panel won't cure it.

If you can run similar wiring from the sensor to the gauge to by pass the existing wiring you should be able to check.

Annoyingly complicated for a minor problem.

Hi, that sounds a good idea. I will ask my dealer to try that.

 

Many thanks

[htrevor]

Derek Uzzell - 2020-02-20 8:39 AM

 

In his original posting Trevor said

 

"I have tried the appropriate Elsan additive overnight, bleach and even 4 litres of cola after seeing one of your posts.”

 

There used to be a webpage provided by a water hygiene specialist that advised on the relative capabilities of agents that might be used to clean leisure-vehicle grey-water tanks. Soft drinks like Coca-Cola had minimal effectiveness (anything a human can drink without dying could hardly be expected to remove crud/scale from inside a plastic tank) and employing a strong bleach solution was the time-honored method.

 

Nowadays there are ‘friendlier’ commercial cleaning products from Dometic, Fenwick, Elsan etc. in fluid or tablet form and several YouTube videos.

 

https://tinyurl.com/t9ymcx5

 

However, it’s peculiar that, after Trevor has emptied the grey-water tank (90 litres capacity), the warning light stops flashing but starts to flash again soon afterwards. As Billggski says, the problem may be due to a wiring fault, but the fact that the warning light does stop flashing temporarily when the tank is emptied seems to indicate otherwise. (From Trevor’s earlier forum postings, I’m doubtful that he will wish to carry out ‘technical’ DIY trouble-shooting.) Putting a cleaning agent into the grey-water tank has failed to cure the problem, so masking the irritating warning light on the control-panel should be an instant 'cheap-and-nasty-but-effective' ploy.

 

I THINK an Amundsen 600D’s habitation electrics may be CBE-made. If that’s correct, it should be practicable to address the problem by disconnecting the plug on the CBE Distribution Box that is cabled to the grey-water tank sensors that (for a CBE system) would normally be a pair of ‘screws’ in the tank’s side near its top. If it’s very difficult to access the sensors on the grey-water tank, just pulling out a single plug on the Distribution Box should be much simpler and definitely stop the light flashing. Of course, if Westfalia had been bloody-minded and installed the Distribution Box where getting at it needed dismantling half the motorhome, that would be another matter...

Thanks Derek, I will add this to my list of comments to show my dealer.

 

Many thanks for your help and the other contributors. Much appreciated.

[Derek Uzzell]

A common means of providing a warning of when a motorhome’s grey-water tank is approaching full involves a pair of ‘screws’ installed one above the other in the tank’s side near its top. (Example of ‘screws’ in following advert.)

 

http://www.rainbow-conversions.co.uk/cbe-motorhome-caravan/waste-water-tank-couple-screws-197-p.html

 

When the ends of the screws that protrude in the tank’s interior are covered by the contents of the tank, this essentially acts as a ‘switch’ that causes a warning-light to illuminate on the motorhome’s control-panel.

 

Each screw has an electrical cable connected to it and temporarily linking the two cables together should cause the warning-light to come on. And, logically, disconnecting either of the cable’s from its screw should prevent the warning-light from illuminating.

 

I accept that Westfalia should have in-depth knowledge of how the equipment they install in their motorhomes functions, but I’d have no qualms about disconnecting one or both of the tank’s sensors as an experiment as I can’t see why doing this should be harmful. Even though doing this would not be a proper ‘cure’ (as the warning-light should only illuminate when the tank is approaching full) it should stop the light flashing. After that, the UK Westfalia dealer could order replacement sensors from Germany, fit them several months later and see if that fixes the problem permanently.

[ColinM50]

Or, the other end of Derek's suggestion, could you disconnect the relevant cable at the control panel? That may be easier especially if you've got to clamber underneath to get at Derek's screws.

 

IF it's easy to get at the connectors on the panel, just disconnect each in turn to identify which are which.

 

Or is that too easy?

[Derek Uzzell]

If Trevor’s Westfalia has a CBE-made control-panel, disconnecting wires at the rear of the panel will not be a practical approach. Instead (as I mentioned earlier) disconnecting the relevant plug at the CBE Distribution Box would be the right way to go. But this, of course, assumes that Trevor’s Westfalia actually HAS an electrical system based round CBE equipment.

 

(If the ‘sensors’ on the tank are accessible and the wires connected to them can be easily disconnected, just disconnect the damn wires and see what happens. :-( :-( )

[htrevor]

Derek Uzzell - 2020-02-23 9:18 AM

 

A common means of providing a warning of when a motorhome’s grey-water tank is approaching full involves a pair of ‘screws’ installed one above the other in the tank’s side near its top. (Example of ‘screws’ in following advert.)

 

http://www.rainbow-conversions.co.uk/cbe-motorhome-caravan/waste-water-tank-couple-screws-197-p.html

 

When the ends of the screws that protrude in the tank’s interior are covered by the contents of the tank, this essentially acts as a ‘switch’ that causes a warning-light to illuminate on the motorhome’s control-panel.

 

Each screw has an electrical cable connected to it and temporarily linking the two cables together should cause the warning-light to come on. And, logically, disconnecting either of the cable’s from its screw should prevent the warning-light from illuminating.

 

I accept that Westfalia should have in-depth knowledge of how the equipment they install in their motorhomes functions, but I’d have no qualms about disconnecting one or both of the tank’s sensors as an experiment as I can’t see why doing this should be harmful. Even though doing this would not be a proper ‘cure’ (as the warning-light should only illuminate when the tank is approaching full) it should stop the light flashing. After that, the UK Westfalia dealer could order replacement sensors from Germany, fit them several months later and see if that fixes the problem permanently.

Yes I have seen the two screws when the van is on the ramp in Uk and Germany. I cannot exactly remember the wire between but if it was that easy to disconnect as I asked them surely they would have done there and then?

[htrevor]

ColinM50 - 2020-02-23 12:19 PM

 

Or, the other end of Derek's suggestion, could you disconnect the relevant cable at the control panel? That may be easier especially if you've got to clamber underneath to get at Derek's screws.

 

IF it's easy to get at the connectors on the panel, just disconnect each in turn to identify which are which.

 

 

Or is that too easy?

 

That was discussed in Germany as well. I am beginning to think that it would have been definitely better to post my problem within a week of leaving Westfalia whilst my memory was fresh, not 2.5 months later. I am afraid I must sound a little vague with answers to various questions but I now have various thoughts from you all and I can now present these to my dealer.

 

Many thanks to everyone.

[Derek Uzzell]

htrevor - 2020-02-23 8:28 PM

 

Yes I have seen the two screws when the van is on the ramp in Uk and Germany. I cannot exactly remember the wire between but if it was that easy to disconnect as I asked them surely they would have done there and then?

 

Trevor

 

Obviously I can’t answer that question.

 

The basic problem is that nobody on this forum seems to know what electrical system your Westfalia Amundsen 600d is fitted with.

 

I’ve suggested (based solely on on-line photos) that your motorhome may have CBE-made equipment, but that’s just a guess. I hesitate to say this, but you should really know by now what equipment is fitted and I’d expect that type of information to be found in the documentation that you should have received when you took delivery of your motorhome.

 

I have attached a wiring schematic of a CBE PC-200 ‘kit’. It will be seen that the connection between the large ‘Distribution Box’ that forms the heart of the system and the WASTE WATER TANK is a single cable that leads to the two ‘screw-sensors’ near the tank’s top. Disconnecting that cable from either (or both) of the screw-sensors should be expected to disable the waste-wate tank’s warning light. Disconnecting at the other end of that cable where it plugs into the Distribution Box should also disable the warning light, but as the screw-sensors are apparently accessible when the motorhome is on a ramp, disconnection at the sensors end of the cable is probably the simplest approach.

 

It should also be apparent that a single cable leads fron the Distribution Box to the control-panel. As I have never needed to remove a CBE control-panel I don’t know how that cable connects to it, but I suspect there is just a single plug on the cable’s end that fits into a single socket on the panel. If that is correct, then disabling the waste-water tank warning light at the control-panel will be less easy (and less logical) than disconnecting the cable that is between the Distribution Box and the waste-water tank.

 

Although disconnecting cables at the tank, the Distribution Box or the control-panel should prevent the warning-light flashing, it woould not explain why the light is ‘false warning‘ by flashing when the tank is near empty, nor would it cure that problem.

 

Masking the warning-light will minimise the irritation factor and disconnecting the tank screws should stop the light operating - but the problem will still be there. If you’ve asked the Westfalia people to fix the problem and been told that disconnecting cabling would not do this, that’s absolutely right. It would (or should) just stop the light flashing but the result would be that there would now be no warning of when the tank approaches full.

 

As it should be easy enough to demonstrate that the light is ‘false warning’ (which is clearly not what should happen) it is the dealer’s responsibility to cure the fault.