Loft tank sizes - too small?

[bassybert]

Just looking up in our loft and thought I'd measure our header tank sizes, as the heating expansion tank looks a lot smaller than we had in our old victorian house.

The central heating expansion tank is roughly 430x300x300mm (W x D x H) in size - is this too small?

We have 7 rads in the house on an open vented system.

The cold water tank that feed the cylinder is a circular one that is 670x500mm in size (W x H).

The heating expansion tank is full of dark, murky water with a mouldy film on top - obviously the entire system needs to be cleansed and a refill with X100 or similar, but was wondering if it needed to be up-sized - a perfect time to do it I suppose if needed.

Can anyone help?

Thanks,

James

 

[45yearsagasman]

Perfectly ok. Just clean it out and set the water level at 4 to5 inches deep by setting the ball valve arm.

 

[bassybert]

Thanks Pete, much appreciated.

At the moment there is no proper lid on the tank, just a small piece of plywood laid on top. I presume it would be better to have a proper fitting lid?

If so, would it need to be tight fitting, or does it need to be able to breathe so to speak?

 

[45yearsagasman]

No lid that you fit will be tight fitting so that won't be a problem. Get something that will fit and stay put, insulate it and you should have no problems. There are some fairly inexpensive plastic tanks that you could fit if you wanted, but I would clean and use the one you have.