My boiler has stopped working, just as the temp turns! It is fine for hot water, but will not work for CH. The alarm lights on the Drayton thermostat were flashing so I've changed the batteries, yet it still will not work beyond heating to about 35 degrees. Then on the display a flashing radiator sign comes up and it cuts out. Pressure is fine, and all rads recently bled. HELP!

Craig, October 2009

depending how long the thermostat programmer lights were flashing low battery before you noticed programmer may now not be in sync with the boiler , somewhere close to the boiler will be the receiver box when the boiler is in use and in sync with the room thermostat you will have a GREEN LIGHT ON if communication between the 2 is lost through batteries run down, you will get a RED LIGHT
the 2 articles (transmitter room stat,and boiler receiver ) need to be re programed so they COMMUNICATE with each other. in the book this is called BONDING. The FLASHING radiator symbol means the boiler is anti cycling

wirecutterman, October 2009