how do i change a rangmaster 55 thermostat?

I am looking for an answer to the same question. I have a horrible feeling that we need to change the entire flame failure device: eg http://cgi.ebay.co.uk/RANGEMASTER-55-FLAME-FAILURE-DEVICE_W0QQitemZ120126172408QQihZ002QQcategoryZ43566QQssPageNameZWDVWQQrdZ1QQcmdZViewItem

I asked a question on their site, maybe they will confirm that.

Stephen
November 2007