It's the classic SCR fault:
Green light comes on, no heating, however your hot water is fine.
You need to replace the capacitor in ur SCR
if you search for "Drayton SCR part" on eBay, you will find me, I am the eBay seller 'bearsy72' , for just a few quid I can send you the part you need and full installation instructions / pictures, should only take 15mins to change.
You will need a soldering iron to complete the fix, if you don’t have one then send the SCR to me and I can change it for you for just a few extra quid, still way way cheaper than shelling out for a new system.
email me at
bach.dai1970 (at) gmail.com
I had to go to eBay as it is easier to keep track of the shipping, feel free to email me direct using the above if you prefer not to use the auction site
Thanks and hope to keep you all warm
Dave Cardiff
November 2012
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