Model S20BRSB21, older unit with the usual rear board fault which has been the subject of an ongoing thread elswhere on the site. This one, the capacitors C1 C5 C6 C7 and C8 (all reading low capacitance), also C26 C27 and C28 were changed and the board refitted and worked. Called back next day, the unit had got down to temperature , then stopped and not restarted. Turned out the motor relay, RL3 had stopped working. Changing this finally did the trick.
Parts sourced from http://www.rapidonline.com, very impressive service, for info their part numbers
1uF 400v 10-4140
220n 400v 10-4136
100n 400v 10-4134
1000uF 63v 11-1426 if needed
16A 24v coil relay 60-4622
Hope this info helps