# Emptying water tank, problem



## orange22 (Mar 7, 2009)

Hi,
Can anyone advise please? i drained the hot water tank with the whole system for winter. It is a cascade system and there are 2 plastic screws on the outside of the body. The larger and lower one undoes and empties the tank. The upper one at he top of the tank is much smaller and just takes a half-turn. think it is just to let air in to the tank as it empies.
It is this small plastic screw that has snapped so will not now screw up. Is this a problem and if so how to fix?


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## Vennwood (Feb 4, 2007)

I would think it would leak when you heat up the water during normal use. When you say snapped off do you mean the head of the screw?

Before you do anything I would check up and get a replacement screw - this will verify the type and give you an idea as to what to expect when getting it out

Usually these screws are stepped, by that I mean it has a land in between the front and rear sections of the shaft or it could be a deep threaded grub screw. You need to get something into the screw such as an easy out (reverse thread drill).


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## trevorf (May 16, 2005)

Have a chat with these guys

www.miriad-products.com

There is a guy there who used to work for Carver and knows all there is to know about Cascade boilers. Sorry but can't remember his name.

Trevor


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## madontour (May 19, 2008)

hi

you are right, the top screw is essentially an air vent to allow the water to drain more smoothly.

However, the tank will leak if it is not tightned up when the tank is filled with water. (I speak from experience)

Try heating a screwdriver and pushing into the bit of the screw you can see - you should get sufficient hold to be able to withdraw the remainder of the grub screw. Replacements are available from most dealer accessory shops.

mike


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