Bosch boiler problem

[hasel5]

Hi there got a worcester greenstrar RF18i that has the following problem

When both channels on programer are off the boiler runs on for a predetermined time for the pump overrun etc as it should. It then seems to fire intermittently after this causing the rads to still get hot with both the channels off.

Have checked all the connections etc and all wired correctly checked the voltages at the boiler all ok not a crossed permanent live with switched live.

Has anyone any ideas ?

Regards Hasel5

I am a bit stumped as not a new install and have inherited from the plumber lol

 

[telectrix]

check and see if the frost stat is turned up too high.

 

[hasel5]

Good point didn't think of that one will phone client and see