Two years ago i had a radiator removed out my livingroom and put into my kitchen,as i had the gas fire and a rad would of been to much,i took out a 12months heating breakdown cover with a large company.i must of called them out over 10 times.they change the diverter,and replaced a pipe plus other parts through out the year,but still the pressure drops,and when i run a hot bath the systems red light comes on and the hot water turns cold and my central heating turns off to.I refused to carry on with the policy and wondering should i buy a new boiler but being a single parent i know this will cost a fortune,if anyone has any idea what this could be please please could you let me know.my boiler is a britony 100.combination boiler...thankyou