Heating system overflow pipes sealed

Geimhreadh

Hi all,
Bought an old house last year and doing a bit of DIY on the plumbing and came across this.
We have an expansion tank in the attic for the heating system but the overflow pipe is sealed up.
Is there any reason this would be done considering the system is not sealed?
We have a oil burner is that helps any.

Thanks for any advice.

Tom44

I presume you are talking about the vent pipe that loops in over the top of the tank rather than the actual over flow pipe which is a hole in the tank 3" from the top edge and then sloping pipe going out over the gutter.

Blanking the vent pipe is a cowboy way to stop pitching, and normally just needs a professional alternation.

Geimhreadh

Thanks Tom44
Looks like a few cowboys things were done to this system. 
I would upload a picture but boards wont allow me because my account is to new. 
They basically bent a qualplex pipe in half to fit it to the immersion heater from the boiler and some how expected it to allow water through.
Will get a plumber out after I have things figured out to vet the whole thing.