# Burstner 748 Draining the Grey Water Tank?



## datasafe

Hi guys

This is a picture of our grey water tank outlet on our Burstner 748.









When I turn the valve through 90deg nowt comes out!! There's probably 70ltrs in the tank so either I'm being stupid, doing something wrong or missing something!

Any ideas please?

John


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## trek

I don't have a Burstner, but my initial thoughts are :-

blue tanks are usually fresh water black tanks grey /waster water

so are you opening the wrong tank ?


the red handled valve locks like a wide bore valve so you should be able to see what is happening when you operate the red lever, do you see the inside ball moving if it does have you tried poking something in through the valve ?

edited - just noticed you have the 748 I would have thought both tanks would have been inside not underneath ?

are the tanks inside but the waste piped down to this value which just happens to look as though it is on side of plastic tank ?


Is this van new to you ?


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## datasafe

Thanks for the reply Trek.

The fresh water tank on the 748 is accessible from inside the garage and is made of a white'ish translucent plastic. I only assumed the blue tank in the picture was the waste grey water tank, I could of course be entirely wrong!!!!  

I have to admit i didn't examine the valve thoroughly as the road was wet :roll: Asking here is just my lazy way!

Cheers

john


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## trek

the position of this valve also looks rather difficult to get to 

needing one to scramble underneath

I would keep looking must be something with easy access .

can you access the other side / inside of that blue box ? is not a wet box / locker is it


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## fdhadi

Hi datasafe,

The grey water tank valve is in the outside battery compartment. Open the hatch, look to your immediate right you should see a lever. 

Also, under the rear belted seat you will find 2 x flaps, lift the one to the left as you look at them. Under here is a storage compartment (plastic tub) that lifts out with a bit of juggling about. Unscrew the large inspection cap that you can see and this has a thin chain connected with a small plug on the end. Pull the chain up and this will also drain the waste water.

You can then flush the tank out from the top but remember to refit the plug.


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## fdhadi

datasafe,

Just looking at that picture you have posted. I think this could be an extra fresh water tank which are sometimes fitted to wash of motorbikes.


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## datasafe

Thanks for the replies.

You're right Trek, I thought it an odd place to put a valve but it was the only one I could find and I purchased some pipe and connectors to bring it to a more accessible location!!!  

Thanks Frank, I'm going to check your suggestions shortly, I'll let you know  

John


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## datasafe

Would I be right in thinking the red lever that 'flashes' at me that I'd not noticed before   is the waste water valve?


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## 747

Yes.


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## trek

Hi Datasafe

just in case you are new to Motorhomes the red & blue pipe work also shown in your last photo each has a yellow drain valve this is the hot (red) & cold water pipes

so when the winter approaches make sure you drain off all the water in your system by lifting these yellow levers vertically & opening all the taps in the middle position (if mixer taps) & also drain the boiler
this should prevent any frost damage to taps or pipework when you are not using the camper.


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## datasafe

Thank you all & thank you Trek for your help.

Yes, We're very new to motorhoming but learning fast  We had our FIRST weekend away in Carmarthen last Friday, Saturday & Sunday and thoroughly enjoyed ourselves.

Looking forward to many more


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## dave-rsvr

sorry cant view picture but red valve is waste tank one but the hose gets blocked sometimes,i stick bit of wire up outlet from underneath and wiggle it and it should clear 
also never drained my hot/cold water as thought burstners fully winerised and insulated and all has been fine


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