# Hot Water Tank Drain Tap/valve Leaks



## Wilmannie (Feb 7, 2010)

Can anyone help with this please
Our 2006 Autocruise Starburst has a Eberspacher Combitronic hot water/blown air heating system. As the water heats the drain tap on the hot water tank leaks. This seems to be getting worse. We could replace the tap but it isn't an ordinary tap and we think it may be a pressure release valve as well as a drain tap.
Does anyone know where or how we can get a replacement valve/tap??


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## trek (May 1, 2005)

Can you take a photo of this drain tap ?


It may help us identify it


my Frankia camper has two plastic drain valves for hot & cold

these have rubber o rings that perish but can easily be changed by pushing out retaining spring & lifting internal tap out of main body


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## ingram (May 12, 2005)

Yes, it is a pressure relief valve and drain valve and it seems they are prone to a bit of leaking. Mine drips a bit when the water is heated due to the increased pressure at that time. You may find that opening and closing it will help reseal it if the seal has some dirt on it.

It is the thing with the red knob shown here:--

http://www.surecal.co.uk/Product/PumpsPlumbing.aspx

I don't know if it is a 3 bar or 4 bar on the Eberspacher Combi but something that I read on another forum suggested that it was a 4 bar originally fitted.

Surecal have them priced at £23 each but if you google for "boat / motohome heating drain valve" or something like that, you will find other suppliers.

These heating systems are also used on boats so you may find these valves available at boat chandlers.

btw the item with the black knob in the above link is an adjustable water mixer valve.

The Eber heats the water to above usable temperature: maybe 80 degrees I think and then when you turn on the hot tap cold water is mixed with the hot according to the valves adjustment. This means that the hot tank's capacity is, in effect, increased because you are drawing less hot then if it was'nt mixed.

hth

Harvey


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## Wilmannie (Feb 7, 2010)

Hi Trek & Harvey
Thank you both so much for your response & I finally managed to get a photo this morning but I can't see how to get it on here, it's too big. But that one looks very like it Harvey. 
Will get the CO to read this when he finishes painting the garden fence! 
We'll get back to you! Many thanks!


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## Wilmannie (Feb 7, 2010)

Again, thanks to you both and thanks Harvey for the link. 
Now we'll just have to decide if the leak is bad enough to warrant a replacement tap. Methinks it must be as it'll be no end of a nuisance if it needs replaced abroad.


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