Problem with pipe over flowing

[Savvy]

Hi guys,
I noticed last week that there was water draining from the gutter on a dry day.
Yesterday I had another look and could see that water was flowing from a pipe on to the roof and down the gutters. It appears that this pipe is contanstly flowing water(about 1lt/20-30 sec)
I can't say how long this has been happening. Although I cleaned the gutters 6 months ago and can't say I noticed it then.
The only thing that has happened in the last few months is that the kids were kneeling on the radiator to look out the back window(upstairs) at some new dogs and knocked it off the wall. The left pipe in to the radiator is not pinched but the right one partially pinched. I'm waiting for the brother-in-law(plumber) to have a look. Could this be part of the problem?
Thanks in advance

 

[Buddyboy]

Water flowing out of a pipe in the roof is normally one of two things.

1. The water tank. This is a storage tank of water that feeds the toilets and normally the bathroom taps. As the water is used, e.g flushing the toilet, the drop in water level in the attic tank operates a valve that fills the tank up again. The valve is controlled by a ball floating on in the tank, connected to a valve via an arm (the mechanism is called a ballcock). Sometimes either the ball gets stuck, or the arm gets stuck, or the valve itself gets stuck. This means that the water is not shut off when the tank is full. If this happens, then there is a pipe above the normal level of the water, that allows the excess to flow safely out of a pipe. This is what you are seeing.

2. The Header Tank. This is the same as above, except it is a smaller tank that holds water for an "open" heating system. If you heating system needs water, then this is supplied from this tank. The tank as the same ballcock arrangement as the water tank above, with the same safety overflow pipe.

As to which one it is, firstly I am assuming you have both. if you have a closed heating system, then you only have a water tank as in 1 above, you will not have a header tank.

If you have a header tank then that, in my opinion, is the most likely culpret. the Water tank is normally drawn and refilled a number of times a day, when the toilets are flushed or the bathroom taps are used. The Header tank is rarely used, and the knock to the radiator may have caused a bit of back pressure in the system that "jiggled" (technical term ) the ballcock and caused it to leak.

In eny event, a trip to the attic is in your future. It is easy if you have access. Go up to the attic and find the water tank. It should be obvious if water is going out of it, both by sight and noise. If water is flowing out, try tapping the ball, or submerging in and letting it pop up again. Flushing the toilet will have the same affect.

If it is the header tank, (which is normally located close to or above the water tank), then try the same thing.

If this does not work, then the valve may need to be replaced or the rubber washer in it needs replacing. It is not a difficult job for a plumber.

 

[Savvy]

Buddyboy,
I appreciate your reply.
I will get up there this weekend and see whats happening.