After using the C/H the boiler looses pressure and red light comes on, H/W is ok as long as I don't use C/H 1st. If I fill pressure to 1.5 bar with water and use C/H, water spills from the over flow. Should I be pumping up expansion vessel instead of using water to build pressure back up ?
howtomendit.com for free repair help, information and advice.
Try fixfault.com to fix home heating systems.