Can anybody help me out there I have just fitted a new rad in the dining room,but it is only warming up at the top. I fear I have either an air lock or I have fitted one too many rads I have 11 rads on the go running from a 50,000 BTU wickes boiler( not combination) pump runs at 2200.The dining room has two rads,both approx 4,000 BTU, fed from the bedroom directly above . any ideas please