hi... the overflow pipe at the gable of the house is continuously running. It stops now and again, usually when the hot water is being used (I think). I have been in the attic and the problem is with the large tank which is full to the brim and over the level of the overflow pipe. The smaller tank's water level is about half full. I know that I need to reduce the water level in the large tank, but I dont know how to permanently fix the problem. Any advice would be greatly appreciated,
I just sorted the problem. Ran all the taps and flushed the toilets to empty the large tank. I tested the ballcock by moving it around a bit and saw that the water did shut off when the ballcock reached a certain height, so I waited until the tank refilled and sure enough, the ballcock reached its max height on the water surface and the valve closed. The ballcock must have become out of alignment during the freeze causing the tank to completely fill and trapping the ballcock under the water keeping the water valve continuously open. I never did this before, and it was easy to fix.