boiler not heating water but can by electric

[surfingmace]

Hi I had a small leaking pipe by my boiler so turned off all water supply and thought by using pfte tape would stop the leak but it seems to be the valve at the end of the piece that I unsrewed where the leak is coming from(very small). When I put it back on and turned all water supply and got rid of all the air in the pipes my boiler system will not heat the water. It is gravity feed from a container in the loft. The only way I can acheive hot water is to turn the electric switch on near the hot water cyclinder.
Any help would be great.
I am not a plumber and am confused why this has happened. The boiler will heat the rads very well just not the water.
Thankyou
Stuart

 

[swbjackson]

Sounds like you are out of your depth to be honest. It could be a multitude of things from an airlock to faulty components. I'd bite the bullet and pay a heating engineer t come in and sort it for you.