Anyone had water leak problems from outlet piper?

not sure why your van' fresh water tank would have two drain holes....generally there is one quick drain outlet, usually a 'bung-type' or 'side tap' type...im guessing you have a bung type (more typical on continental vans)...

are you saying that this bung doesnt sit snuggly?

normally, these bungs are screwed in (and out for draining) by a long threaded shaft, reaching down to the bottom of the tank. sometimes these can be a bit iffy when securing the bung....

if you put a large piece of cardboard under the van you will be able to identify exactly where the water is coming from.

its possible that the water is coming from (say) the frost protection dump valve, as these are prone to drip....

We have a Chausson 2014 Best of 510 MH and for two nights running the half full storage tank has drained overnight we think through the outlet nozzles (it has 2). We find the outlet nozzles difficult to try and get them to stop dripping at the best of times. Anyone el had similar issues with this system?

 

The Chausson tank drain is a push on cap with "O Ring" type speals, which might not be sitting properly or may be damaged.  I think replacements are available from caravan dealers, as they are used in most flex pipe push on fittings.  Try cleaning and checking the seals.  If you have two (our 610 only has one) and both have failed you may be being a little rough with them.

As BB mentioned it may well be worth opening and closing the dump valves on the water heater and fresh tank min level pipe.  If they haven't fully closed they will drip, if further open you will hear the pump trying to purge the system.

We have a 2014 Chausson Flash 510 and that has two drain outlets from the fresh water tank s well. These outlets are standard 15mm plastic pipe and have a push-on stop end fitted which has to be pulled off to drain. I was never happy with that as the stop ends never seemed completely secure and having to pull them on and off was bound to make leaks more likely. I replaced them with a plastic push-fit tap, which you can get in any DIY store. This means the fitting stays in situ and you just turn the tap to drain  

This is a link to what I bought from Screwfix. It seems to work well 

We have a 2014 Chausson Flash 510 and that has two drain outlets from the fresh water tank s well. These outlets are standard 15mm plastic pipe and have a push-on stop end fitted which has to be pulled off to drain. I was never happy with that as the stop ends never seemed completely secure and having to pull them on and off was bound to make leaks more likely. I replaced them with a plastic push-fit tap, which you can get in any DIY store. This means the fitting stays in situ and you just turn the tap to drain  

 

 

 I have been thinking of doing this myself.