Hello everyone..... anyone?
So, a bit of drama happened today at the parents house, water crashing through the ceiling is always fun.
Glow worm fuelsaver, gravity fed open/vented system. We found that when the main water supply was turned on cold water was rushing out of the vent pipe into the F&E tank. With the mains switched off the CH runs perfectly fine. The rents did mention that over the past few days the CH and DHW wasn't get as warm as normal.
The system has been in place for several years (~30) with out anything like this happening before. I have been spending the past few hours trawling through internet forums but most posts talk about the F&E tanks becoming warm with water being pushed up the CH pipe when there is a failure in the tank. I have seen the water myself it was so extreme that it was almost like the cold water was just coming straight through.
Any advice would be greatly received.