water leaking from my overflow pipe

[Nigey007]

hi there, for the past year (i think) my glowworm compleheat fuel saver 30 central heating boiler seems to run out of water, the low water pressure light comes on and the heating will not switch on. after further investigation i noticed that water was leaking through the overflow pipe constantly and would empty in a day. i was told to change the pressure valve as this could have got jammed, i did this but to my luck no change so after speaking to a friend of a friend etc i had a chap to come and have a quick look at it, to see if he could find out the problem. when he found the vessel he poked the valve and water came straight out indicating that my vessel was full of water and the rubber gasket inside is probably worn and has no pressure and a new vessel will sort out the leakage due to the pressure. he said that the boiler would have to come of the wall and could cost a lot but he then said that an external vessel could be fitted to the system. i found that my vessel is 5 litres and he recommended a 7 litre vessel saying that this would be more efficient is this so and would this cure the problem. what would happen if i tried pressuring the vessel with a pump to 1.5 bar is this safe, and if i were to fit a new vessel would i fit it anywhere or say the return pipe etc. and to finish off does it matters what vessel i use as its going to be an external one as long as the specifications are correct i.e. 5/7 litre would this be the case. i really hope you can help as its going to be a cold one this year and its terrible to wake up and to come home after work to a f f f f reezing house fandamtastic site by the way! kind regard nige

 

[ChrisR]

what would happen if i tried pressuring the vessel with a pump

FOrget it. Air would just dissolve in the water.

External pressure vessels can go anywhere, trad itionally on the return where it's cooler. Any type.