Worcester Greenstar 24i junior - No Central heating.

[stickle]

Hi Did you manage to get to the bottom of this problem? my boiler a 28i junior is doing the very same thing?

Thanks

Andy

Hi Andy - Yes, The fault was/is with the 'Drayton Digistat SCR' receiver not operating its on-board relay (should be about 24v but found to be less than 6v). I read on the web that this is a common fault that can be fixed by replacing the 0.68 uF 275v ac rated capacitor that supplies it. I have sent for a replacement (from China). [google - Drayton Digistat SCR & you should find this info]. In the mean time I am running the heating via a cheap mechanical room stat. and a timer that sends a 'live' to 'L return' on the boiler control card. I can pick up this connection at the Drayton connector block when the wireless system is removed so there is no need to open up the boiler. The temporary system works well so even if the cap. doesn't do the job I'm quite happy with this 'primitive' arrangement. - Good luck with your 28i. & beware Live wires !!

ps. press & hold in the 'maintenance button' [on the front of the boiler] for at least 12 secs. - button should light up orange - This should give you a FULL blast of heat to the radiators for about 15 mins. & then shut its self down again . Assuming your water pressure is above 1 BAR etc.

Update. new 0.68uF cap fitted today. This produced 10v across relay (ON when 'Demand Heat') so still not enough volts. I have re-fitted original cap. in parallel with new cap. Volts now up to 15.2 & relay now works! something in the circuit (too small for my old eyes) must be taking to much current so I will keep an eye on the board for a few days & hope for the best before I re-fit it.

 

[nicam49]

Hi Stickle and anyone else following this thread with a similar fault, I see the OP hasn't been on here for sometime, and I trust all is well! Just wanted to look at Stickle's album pics mentioned, but being told there isn't one! My own Digistat is the T45 model, does anyone know if the 'fix' applies to this old version? My boiler fault is no CH, but when Digistat triggers, it fires up for about 20 secs then off again. Even in maintenance mode... Thanks!