Hi thanks for your quick responses
I went and got a honeywell style super basic 3 wire analogue dial one
I have a multimeter so i guess i'll test for an output
Between now and then if any other ideas come to mind - by all means fire away !
Worcester heatslave 15/19 (est 20 yr old)
Not responding to stat requests - otherwise working in all other respects
new stat tested, has worked for a time, then stops responding so intermittent issue
Adjusting the heating level dial will still fire it up & it will finish its run till up to...