This valve controls the level of water in the cistern via a plastic float which sits on the surface of the water.
Water tank in attic overflowing.
If its the big tank that feeds your hot water cylinder it might be that the water level is too high in tank.
Freezing being in a loft space that s often unheated can mean that the water in the header tank is susceptible to freezing during the winter.
The small water tank in you attic is for your central heating it should have a long 3 4 pipe in the shape of an inverted u above it.
If you are not sure why there are two water tanks in your loft it is probably because the property has or used to have a vented central heating system.
Water from the mains is fed into the larger of the tanks which is the cold water storage tank.
That mysterious pipe is the overflow from the cold water header tank also called a cistern in your attic.
If you find the hot water tank overflow pipe dripping at some point we will have to come to an assumption that there is some sort of a defect in your overflow valve.
But we can dig deeper on this later on.
If the tank overfills excess water flows safely via the overflow to the outdoors.
If the overflow is not cured and sti.
You need to check the ball on the valve isn t full of water or hasn t slipped down the arm of the valve allowing the water level to get too high in the tank.
As the water level in the cistern rises the float pushes a washer onto the valve seating a plastic nozzle inside the valve body.
If the water in the tank or cistern fills up to a higher level than it should the excess water flows down the overflow pipe and runs outside rather than leaking into the room.
They re a vital part of your home s plumbing system.
An overflow pipe leads from a water storage tank or cistern inside your home to the outside.
If that is over flowing and the ballcock is not leaking the the problem is what plumbers call pitching ie water from your heating system is pitching into the small tank and causing it to overflow.
But still you cannot come into a solid conclusion as yet since it is just an indication of a malfunction in your overflow valve.
So when the water heats up and expands the tank overflows.
Water is trickling out from the pipe and down onto the ground.