Draing heating system

[Newheatingdiyer]

Hi,

I have oil fire central heating. There is small water tank in the attic. When I drain the heating system from the lowest point most of the system is drained. I noticed the tank was still full. The system refuses to fill from the tank. I tried to put water through the system via the boiler. While the water gets into the tank but the water does not drain. Any idea how I can resolve the issue?

 

[Elkato531]

Sounds as if the feed pipe into the heating system from the header tank is blocked (I found a mouse in one once). If the system has an air seperater, this is a common place for crud to build up and cause a blockage.

 

[Newheatingdiyer]

Sounds as if the feed pipe into the heating system from the header tank is blocked (I found a mouse in one once). If the system has an air seperater, this is a common place for crud to build up and cause a blockage.

I connected the cold water to the boiler and tried to fill the system. Water got to the tank, if I am correct the pipe is not blocked or could it be?

 

[Elkato531]

The water coud be getting into the tank via the vent pipe. If loosly stick a bit of tissue into the vent and try it again this will tell if thats whats happening.

 

[Newheatingdiyer]

The water coud be getting into the tank via the vent pipe. If loosly stick a bit of tissue into the vent and try it again this will tell if thats whats happening.

That is going to be easy to check. I can use a electrical fishing wire as the vent is close to the tank.

 

[Newheatingdiyer]

The water coud be getting into the tank via the vent pipe. If loosly stick a bit of tissue into the vent and try it again this will tell if thats whats happening.

That is going to be easy to check. I can use a electrical fishing wire as the vent is close to the tank.

The pipe seems clear. I also blow down type and that lenght of the pipe seem clear.